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结合倒置残差模块和可微分RANSAC算法的点云配准模型
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作者 李维乾 葛文豪 陈金广 《计算机与现代化》 2026年第2期1-10,共10页
针对复杂和存在遮挡的点云数据整体和局部特征融合程度低,以及传统鲁棒估计算法无法集成到深度学习训练流程的问题,本文提出一种基于改进PointNet++和随机采样一致算法的点云配准网络模型。首先,使用融合倒置残差模块的PointNet++网络... 针对复杂和存在遮挡的点云数据整体和局部特征融合程度低,以及传统鲁棒估计算法无法集成到深度学习训练流程的问题,本文提出一种基于改进PointNet++和随机采样一致算法的点云配准网络模型。首先,使用融合倒置残差模块的PointNet++网络提取局部点云特征,生成融合全局和局部特征信息的特征描述符;其次,使用局部特征Transformer模块生成暂定的点对应和置信度分数;随后,引入神经采样器以保证RANSAC采样过程的可微分性,并使用可微分的几何求解器计算出点云对之间的刚性变换矩阵;最后,设计可训练质量函数以在每次迭代中优化评估指标,将鲁棒估计算法集成到训练流程中,最终完成点云配准。在3个公开的大规模点云数据集3DMatch、ETH和KITTI上的多次对比实验结果表明,本文方法在3DMatch上的特征匹配召回率达到98.4%,较SpinNet网络提高了0.8百分点;在ETH和KITTI上的特征匹配召回率和正确率分别达到98.5%和99.57%,较SpinNet网络分别提高了5.7百分点和0.5个百分点。在处理多个密度不均匀、存在遮挡的复杂点云数据集时,本文方法的表现优于现有先进方法,能有效提高配准精度。 展开更多
关键词 点云配准 鲁棒估计 特征描述符 PointNet++ 倒置残差 随机采样一致算法
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城市环境下基于RANSAC的鲁棒辐射源定位方法
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作者 冯春华 庄忱 +2 位作者 宜娜 孙雅轩 赵洪博 《信息对抗技术》 2026年第1期101-111,共11页
复杂城市环境下,由于建筑物遮挡,信号干扰较为普遍,辐射源定位受多径、非视距(non-line-of-sight, NLOS)等干扰严重,定位精度显著降低。传统到达时间差(time difference of arrival, TDOA)、到达频率差(frequency difference of arrival... 复杂城市环境下,由于建筑物遮挡,信号干扰较为普遍,辐射源定位受多径、非视距(non-line-of-sight, NLOS)等干扰严重,定位精度显著降低。传统到达时间差(time difference of arrival, TDOA)、到达频率差(frequency difference of arrival, FDOA)定位方法的定位精度和误差检测剔除有限。针对以上问题,提出了在城市环境下,采用随机抽样一致性(random sample consensus, RANSAC)算法,对空地协同接收机布局下的TDOA/FDOA协同定位进行误差检测与剔除。相比于单一的辐射源定位方法,TDOA/FDOA协同定位能兼顾时差与频差,同步获取移动辐射源位置和速度信息,定位性能较好;空地协同接收机布局能够为定位算法提供更多观测数据,而且在高度方向能够提供额外的观测角度和时差频差数据;RANSAC通过剔除数据误差较大的接收机,获取“内点集”用于最小二乘解算,能够有效提高定位算法的定位精度和鲁棒性。仿真实验结果表明:所提方法具有较好的定位效果,理想情况下定位误差约1.5 m,均方根误差(root mean square error, RMSE)约1.8 m;RANSAC误差检测与剔除算法可以排除多径/NLOS干扰,定位精度提高约45%,RMSE约6 m,能够有效提高定位算法的定位精度和鲁棒性。 展开更多
关键词 辐射源定位 TDOA FDOA ransac
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基于RANSAC与改进A^(*)算法的果园移动机器人路径规划研究
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作者 王明之 吕强 +3 位作者 蒋杰 林刚 唐超 张皓杨 《西南大学学报(自然科学版)》 北大核心 2026年第1期216-228,共13页
针对果园移动机器人在全局路径规划中存在的搜索时间长、安全性低、冗余节点多、路径不平滑以及行间作业精度不高等问题,研究提出一种基于RANSAC(Random Sample Consensus)算法与改进A^(*)算法的路径规划方案。该方案首先利用RANSAC算... 针对果园移动机器人在全局路径规划中存在的搜索时间长、安全性低、冗余节点多、路径不平滑以及行间作业精度不高等问题,研究提出一种基于RANSAC(Random Sample Consensus)算法与改进A^(*)算法的路径规划方案。该方案首先利用RANSAC算法拟合树行直线并提取果树行间中线,为后续改进A^(*)算法提供最优中线参考路径;然后,在A^(*)算法中引入中线栅格缩减策略,引导A^(*)算法优先将中线作为最终路径;接着,对预估函数进行优化以提高运算效率,加入排斥力场函数以提升路径安全性;最后,结合安全距离阈值剔除冗余节点方法以消除多余节点,并采用三次均匀B样条曲线对路径进行平滑处理。在A^(*)算法仿真对比试验中,本文改进A^(*)算法相对于其他算法计算效率更高,生成路径更为安全平滑;在果园仿真栅格地图算法对比试验中,本文算法对于其他算法能规划出更高质量的行间中线路径;在模拟果园路径跟踪试验中,本文算法横向偏差均小于其他算法,适用性更强。 展开更多
关键词 移动机器人 路径规划 A^(*)算法 随机抽样一致算法 果园
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Strong Laws of Large Numbers for Sequences of Blockwise m-Dependent and Sub-Orthogonal Random Variables under Sublinear Expectations 被引量:1
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作者 Jialiang FU 《Journal of Mathematical Research with Applications》 2026年第1期103-118,共16页
In this paper,we establish some strong laws of large numbers,which are for nonindependent random variables under the framework of sublinear expectations.One of our main results is for blockwise m-dependent random vari... In this paper,we establish some strong laws of large numbers,which are for nonindependent random variables under the framework of sublinear expectations.One of our main results is for blockwise m-dependent random variables,and another is for sub-orthogonal random variables.Both extend the strong law of large numbers for independent random variables under sublinear expectations to the non-independent case. 展开更多
关键词 sublinear expectations strong law of large numbers blockwise m-dependent suborthogonal random variables
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Asymptotics of the Maximum Sum of Randomly Stopped Finite Random Walks with Subexponential Distribution
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作者 CAO Shuxia LIU Zixin ZHANG Shuguang 《应用概率统计》 北大核心 2026年第1期75-89,共15页
We study a finite number of independent random walks with subexponentially distributed increments and negative drifts.We extend the one-dimensional results to finite and fully general stopping times.Assuming that the ... We study a finite number of independent random walks with subexponentially distributed increments and negative drifts.We extend the one-dimensional results to finite and fully general stopping times.Assuming that the distribution of the lengths of these intervals is relatively light compared to the distribution of the increments of the random walks,we derive the asymptotic tail distribution of the partial maximum sum over the random time interval. 展开更多
关键词 subexponential distribution maximum sum random walk ASYMPTOTICS
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基于RANSAC算法的结构面产状测量方法研究
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作者 杨海林 刘军 《测绘与空间地理信息》 2026年第3期7-10,共4页
岩体结构面的几何特征参数是影响岩体稳定性的主要因素。传统结构面测量方法作业效率低、危险性高,本文基于RANSAC算法的识别和迭代原理,提出了一种高精度的简便快捷提取结构面的方法。首先,通过主成分分析法选取局部点云进行参考平面... 岩体结构面的几何特征参数是影响岩体稳定性的主要因素。传统结构面测量方法作业效率低、危险性高,本文基于RANSAC算法的识别和迭代原理,提出了一种高精度的简便快捷提取结构面的方法。首先,通过主成分分析法选取局部点云进行参考平面的拟合;随后借助RANSAC算法进行迭代处理,识别并剔除噪声点,自动计算岩体结构面;最后,根据法向量坐标转换获取结构面的产状信息。运用该方法处理仿真数据和实测数据,能有效地剔除噪声点,并适应不同密度与规模的点云数据,具有较强的鲁棒性,自然岩体结构面倾向和倾角的计算结果与实际数据差值小于2°。结果表明,本方法可以高效、可靠地识别提取自然岩体的结构面信息,满足工程实际的应用。 展开更多
关键词 ransac算法 PCA算法 结构面产状 三维激光点云
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基于改进RANSAC算法的电网数字孪生多帧图像配准
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作者 周鹏 肖学权 +2 位作者 苏岭东 张潇 滕松 《信息技术》 2026年第3期36-41,共6页
由于电网环境的复杂多变,如背景干扰、设备布局的动态变化以及图像质量差异等因素,导致在复杂的电网背景中无法有效地提取关键点。因此,提出了一种基于改进RANSAC算法的电网数字孪生多帧图像姿态配准方法。利用SIFT算法在电网数字孪生... 由于电网环境的复杂多变,如背景干扰、设备布局的动态变化以及图像质量差异等因素,导致在复杂的电网背景中无法有效地提取关键点。因此,提出了一种基于改进RANSAC算法的电网数字孪生多帧图像姿态配准方法。利用SIFT算法在电网数字孪生多帧图像中检测关键点,并通过相似性度量进行粗配准。采用空间一致性检测原理和PROSAC算法改进RANSAC算法,利用改进后的算法剔除初始关键匹配点集中的外点,实现电网数字孪生多帧图像姿态的精配准。实验结果表明,该方法的关键点检测精度高、图像姿态配准效果好。 展开更多
关键词 改进ransac算法 电网数字孪生多帧图像 图像姿态配准 SIFT算法
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Causal relationships of inflammatory cytokines and serum metabolites with colorectal carcinoma: A Mendelian randomization study
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作者 FENG Sisi XIAO Xiaomin +2 位作者 ZHOU Manli HUANG Zixin ZHONG Baiyun 《中南大学学报(医学版)》 北大核心 2026年第1期118-128,共11页
Objective:The incidence and mortality of colorectal carcinoma(CRC)continue to rise globally,highlighting the need to identify modifiable risk factors for early detection and prevention.Previous studies have demonstrat... Objective:The incidence and mortality of colorectal carcinoma(CRC)continue to rise globally,highlighting the need to identify modifiable risk factors for early detection and prevention.Previous studies have demonstrated significant associations between CRC risk and various serum metabolites as well as inflammatory cytokines;however,due to limitations in study design and potential confounding factors,the causal relationships remain unclear.This study aims to investigate the causal relationships between inflammatory cytokines,serum metabolites,and CRC risk,providing a theoretical basis for the development of novel early diagnostic biomarkers and therapeutic targets.Methods:A two-sample Mendelian randomization(MR)design was applied using summary statistics from genome-wide association studies(GWAS).Instrumental variables(IVs)were derived from:1)metabolomics GWAS data of 1400 serum metabolites(n=8299);2)cytokine GWAS data of 91 inflammatory factors(n=14824);and 3)CRC risk data from the FinnGen consortium(6847 cases and 314193 controls).The primary analysis was conducted using the inverse-variance weighted(IVW)method,with sensitivity analyses performed using MR Egger regression and the weighted median method.Effect estimates including odds ratios(OR),95%confidence intervals(CI),and false discovery rates(FDR)were calculated.Results:MR analysis indicated that higher levels of axin-1(AXIN1)(OR=0.84195%CI 0.714 to 0.991)and Fms-related tyrosine kinase 3 ligand(Flt3L)(OR=0.916,95%CI 0.844 to 0.994)were associated with a reduced risk of CRC.In contrast,higher levels of Delta/Notchlike epidermal growth factor-related receptor(DNER)(OR=1.119,95%CI 1.009 to 1.241)and vascular endothelial growth factor A(VEGF-A)(OR=1.078,95%CI 1.011 to 1.150)were associated with an increased risk of CRC(all P<0.05).Metabolomics association analysis further identified 144 serum metabolites significantly correlated with these four key inflammatory cytokines(FDR<0.05),suggesting that they may regulate CRC risk through inflammatory pathways.Conclusion:Specific inflammatory cytokines and serum metabolites have causal relationships with the risk of CRC.These findings provide insights for further exploration of potential risk factors and the development of effective prevention strategies for CRC. 展开更多
关键词 inflammatory cytokines serum metabolites colorectal carcinoma Mendelian randomization genome-wide association study metabolomics analysis
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RANSAC算法在原子钟完好性监测的应用
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作者 罗熙衍庆 武文俊 《仪器仪表学报》 北大核心 2026年第2期199-210,共12页
原子钟是卫星导航与精密守时系统的核心装置,其输出信号的质量常受到异常的影响。针对原子钟完好性监测中传统最小二乘法(OLS)对复杂异常模式适应性不足的问题,提出了一种基于随机采样一致性(RANSAC)的抗干扰建模与异常修复方法。该方... 原子钟是卫星导航与精密守时系统的核心装置,其输出信号的质量常受到异常的影响。针对原子钟完好性监测中传统最小二乘法(OLS)对复杂异常模式适应性不足的问题,提出了一种基于随机采样一致性(RANSAC)的抗干扰建模与异常修复方法。该方法利用RANSAC算法在含噪数据中构建高鲁棒性的相位或频率预测模型,结合内点优化策略与基于中位数绝对偏差(MAD)的动态阈值机制,实现对异常点的精准检测与修复。实验利用氢原子钟和铯原子钟实测数据,构建了包含离群值、相位跳变以及复合异常的数据集进行验证,并与传统方法、抗差卡尔曼滤波(RKF)及M估计法进行了对比。结果表明,所提方法在多种异常场景下均表现优异。在抗差算法对比时,氢钟异常测试中RANSAC方法的F1分数达到0.9538,优于M估计(0.9247)和最优参数下的RKF(0.8177);铯钟异常测试中RANSAC方法的F1分数略低于最优参数下的RKF;在参数失配的非理想条件下,RKF性能大幅下降。收敛性分析显示,在选取合理最小子集与迭代次数时,该方法拟合结果显著收敛(拟合斜率的标准差为0)。此外,算法单次滑动窗口处理延迟为毫秒量级,在原子钟1 Hz采样率下计算负载<1%,满足实时完好性监测需求。实验结果验证了RANSAC算法在无需精确噪声先验信息情况下的适应性与鲁棒性,为精密时频系统的自主完好性监测提供了可靠的技术支撑。 展开更多
关键词 原子钟 完好性监测 异常检测 随机采样一致性 抗差估计
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Randomized trial of robotic percutaneous coronary intervention:feasibility achieved,but questions remain on generalizability and training
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作者 Abdullah Saad Baneen Javaid Arain 《Journal of Geriatric Cardiology》 2026年第2期131-132,共2页
The important work of Yu,et al.[1]who presented one of the first randomized controlled trials(RCTs)to directly compare robot-assisted and manual percutaneous coronary intervention(PCI),is commendable;offering importan... The important work of Yu,et al.[1]who presented one of the first randomized controlled trials(RCTs)to directly compare robot-assisted and manual percutaneous coronary intervention(PCI),is commendable;offering important insights into the feasibility and outcomes of this emerging technology.While the analysis is timely,several issues warrant further consideration. 展开更多
关键词 FEASIBILITY GENERALIZABILITY percutaneous coronary intervention pci randomized controlled trials rcts training robotic percutaneous coronary intervention randomized controlled trial
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Random State Approach to Quantum Computation of Electronic-Structure Properties
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作者 Yiran Bai Feng Xiong Xueheng Kuang 《Chinese Physics Letters》 2026年第1期89-104,共16页
Classical computation of electronic properties in large-scale materials remains challenging.Quantum computation has the potential to offer advantages in memory footprint and computational scaling.However,general and v... Classical computation of electronic properties in large-scale materials remains challenging.Quantum computation has the potential to offer advantages in memory footprint and computational scaling.However,general and viable quantum algorithms for simulating large-scale materials are still limited.We propose and implement random-state quantum algorithms to calculate electronic-structure properties of real materials.Using a random state circuit on a small number of qubits,we employ real-time evolution with first-order Trotter decomposition and Hadamard test to obtain electronic density of states,and we develop a modified quantum phase estimation algorithm to calculate real-space local density of states via direct quantum measurements.Furthermore,we validate these algorithms by numerically computing the density of states and spatial distributions of electronic states in graphene,twisted bilayer graphene quasicrystals,and fractal lattices,covering system sizes from hundreds to thousands of atoms.Our results manifest that the random-state quantum algorithms provide a general and qubit-efficient route to scalable simulations of electronic properties in large-scale periodic and aperiodic materials. 展开更多
关键词 periodic materials random state circuit random state quantum algorithms electronic structure properties density states aperiodic materials quantum algorithms quantum computation
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High Throughput Random Access:Sign-Compute Diversity Slotted ALOHA
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作者 Xu Yu Wang Zhenyong +1 位作者 Cui Chen Guo Qing 《China Communications》 2026年第1期81-91,共11页
In this paper,we propose a random access scheme termed sign-compute diversity slotted ALOHA(SCDSA).The SCDSA scheme combines diversity transmission with compute-and-forward.Without considering the capture effect and m... In this paper,we propose a random access scheme termed sign-compute diversity slotted ALOHA(SCDSA).The SCDSA scheme combines diversity transmission with compute-and-forward.Without considering the capture effect and multiple user detection techniques,our scheme can reach a high throughput of 0.98 without feedback under finite frame size settings,where the upper bound on performance is 1.Moreover,a lower bound on throughput performance is derived,which is tight in some parameter settings and can be used to approximate theoretical performance.Simulation results validate our analysis and confirm the advantages of our proposed scheme. 展开更多
关键词 compute-and-forward diversity transmission random access slotted ALOHA THROUGHPUT
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Dissecting the Causal Association between Body Fat Mass and Obsessive-Compulsive Disorder:A Two-Sample Mendelian Randomization Study
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作者 Meiling Hu Zhennan Lin +2 位作者 Hongwei Liu Yunfeng Xi Youxin Wang 《Biomedical and Environmental Sciences》 2026年第1期36-45,共10页
Objective Previous studies link lower body mass index(BMI)with increased obsessive-compulsive disorder(OCD)risk,yet other body mass indicators may be more etioloically relevant.We dissected the causal association betw... Objective Previous studies link lower body mass index(BMI)with increased obsessive-compulsive disorder(OCD)risk,yet other body mass indicators may be more etioloically relevant.We dissected the causal association between body fat mass(FM)and OCD.Methods Summary statistics from genome-wide association studies of European ancestry were utilized to conduct two-sample Mendelian randomization analysis.Heterogeneity,horizontal pleiotropy,and sensitivity analyses were performed to assess the robustness.Results The inverse variance weighting method demonstrated that a genetically predicted decrease in FM was causally associated with an increased OCD risk[odds ratio(OR)=0.680,95%confidence interval(CI):0.528–0.875,P=0.003].Similar estimates were obtained using the weighted median approach(OR=0.633,95%CI:0.438–0.915,P=0.015).Each standard deviation increases in genetically predicted body fat percentage corresponded to a reduced OCD risk(OR=0.638,95%CI:0.455–0.896,P=0.009).The sensitivity analysis confirmed the robustness of these findings with no outlier instrument variables identified.Conclusion The negative causal association between FM and the risk of OCD suggests that the prevention or treatment of mental disorders should include not only the control of BMI but also fat distribution and body composition. 展开更多
关键词 Mendelian randomization Body fat mass Obsessive-compulsive disorder Causal inference
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A Bidirectional Mendelian Randomization Study on the Causal Association between Psoriasis and Psychiatric Disorders
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作者 Bingting LI Xuefeng LI 《Medicinal Plant》 2026年第1期57-60,共4页
[Objectives]To investigate the potential causal relationship between psoriasis and common mental disorders,and to provide genetic epidemiological evidence for the early intervention of mental comorbidities.[Methods]Ba... [Objectives]To investigate the potential causal relationship between psoriasis and common mental disorders,and to provide genetic epidemiological evidence for the early intervention of mental comorbidities.[Methods]Based on publicly available large-scale GWAS data,a bidirectional Mendelian randomization(MR)approach was employed to assess the causal associations between psoriasis and major depressive disorder(MDD),bipolar disorder,schizophrenia,and anxiety disorders.The inverse variance weighted(IVW)method served as the primary analytical tool,supplemented by sensitivity analyses using MR-Egger and weighted median methods.Additionally,a subgroup analysis was conducted for psoriatic arthritis(PsA).[Results]Forward MR analysis revealed a significant positive causal association between the genetic predisposition to psoriasis and bipolar disorder as well as MDD,whereas no significant causal relationship was observed with schizophrenia or anxiety disorders.The reverse MR analysis found no causal effect of mental disorders on psoriasis.Subgroup analysis of PsA indicated that its genetic predisposition was significantly associated with the risk of bipolar disorder.The results of various sensitivity analyses and pleiotropy tests supported the robustness of the conclusions.[Conclusions]This study provides genetic evidence supporting a causal link between psoriasis and both MDD and bipolar disorder.In particular,patients with PsA are at a higher risk of developing bipolar disorder,highlighting the need to strengthen early screening and intervention for mental health in clinical management. 展开更多
关键词 PSORIASIS Mental disorders Major depressive disorder Bipolar disorder Mendelian randomization
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Causal Effects of Diet and Gut Microbiota on Chronic Respiratory Diseases:A Mendelian Randomization Study
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作者 ZHU Ying GUO Yufang +5 位作者 LI Longjie SUN Meiling OUYANG Huixia ZHANG Yunlei YANG Yang MA Xiuqin 《激光生物学报》 2026年第1期35-52,共18页
Although diet and gut microbial composition have been linked to chronic respiratory diseases,these associations remain difficult to interpret because of confounding and reverse causation.The gut-lung axis provides a p... Although diet and gut microbial composition have been linked to chronic respiratory diseases,these associations remain difficult to interpret because of confounding and reverse causation.The gut-lung axis provides a plausible framework for this interaction,yet direct genetic evidence is limited.Using a two-step,two-sample Mendelian randomization(MR)framework,supplemented by multivariable MR(MVMR)to adjust for pleiotropic effects and Benjamini-Hochberg false discovery rate(FDR)correction for multiple testing,we assessed the causal contributions of dietary habits and gut microbial taxa to major chronic respiratory diseases.We identified 22 dietary factors with causal effects on disease risk and 225 microbial taxa that acted as independent risk or protective contributors.Mediation analyses further showed that the effects of 12 dietary habits were transmitted through 32 specific microbial taxa.Notably,genetically predicted pork intake increased the risk of chronic obstructive pulmonary disease(COPD)(OR=10.53,95%CI[8.54,13.00]),an effect partly mediated by elevated abundance of CAG-485 sp002404675.In contrast,bread consumption conferred protection against asthma(OR=0.68,95%CI[0.64,0.72]),whereas this benefit was offset by approximately 45%through a pathway involving reduced Veillonella abundance.Collectively,these findings provide genetic support for the gut-lung axis and demonstrate that the gut microbiome functions as a causal mediator linking diet to chronic respiratory disease risk.However,since this study was based on individuals of European ancestry,caution is warranted when generalizing these causal estimates to non-European populations,such as East Asian groups.This work suggests new opportunities for microbiota-targeted prevention and therapeutic strategies. 展开更多
关键词 Mendelian randomization gut microbiome respiratory disease DIETARY European descent populations
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Causal effect of obesity on cataract and mediating roles of metabolites:a Mendelian randomization study
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作者 Chen Li Jiao-Man Wang Wei-Hua Yang 《International Journal of Ophthalmology(English edition)》 2026年第3期564-574,共11页
AIM:To investigate the causal effect of obesity on cataract risk and explores the potential mediating roles of metabolites using Mendelian randomization(MR).METHODS:Summary-level data from large-scale genome-wide asso... AIM:To investigate the causal effect of obesity on cataract risk and explores the potential mediating roles of metabolites using Mendelian randomization(MR).METHODS:Summary-level data from large-scale genome-wide association studies to examine the relationship between obesity and cataract were utilized.Obesity-related traits,including body mass index(BMI),waist-to-hip ratio(WHR),and waist circumference(WC).A two-sample MR approach was employed to assess the causal effect of obesity on cataract risk,while potential mediators were identified from suitable genome-wide association studies(GWAS)datasets.Additionally,a metabolic pathway analysis was conducted.RESULTS:An increase of 1 standard deviation(SD)in BMI,WHR,and WC was associated with a significantly higher risk of cataract(BMI:odds ratio(OR)1.0017,95%confidence interval(CI):1.0001-1.0032,P=0.0320;WHR:OR 1.0029,95%CI:1.0006-1.0051,P=0.0129;WC:OR 1.0020,95%CI:1.0001-1.0038,P=0.0390].These associations remained robust after adjusting for confounding factors in multivariable MR analysis.Furthermore,a two-step MR analysis identified eight potential metabolic mediators,with one mediator showing a significant causal role in the relationship between obesity and cataract.CONCLUSION:This work highlights the importance of addressing obesity as a modifiable risk factor for cataracts,particularly through metabolic pathways. 展开更多
关键词 OBESITY CATARACT Mendelian randomization body mass index waist-to-hip ratio waist circumference
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Association between asthma and myopia:the NHANES database and Mendelian randomization analysis
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作者 Ya-Jing Zheng Ji-Fa Kuang +1 位作者 Fei-Lan Chen Wen-Bin Huang 《International Journal of Ophthalmology(English edition)》 2026年第1期132-139,共8页
AIM:To comprehensively assess the relationship between asthma and myopia based on the National Health and Nutrition Examination Survey(NHANES)database combined with Mendelian randomization(MR).METHODS:Initially,20497 ... AIM:To comprehensively assess the relationship between asthma and myopia based on the National Health and Nutrition Examination Survey(NHANES)database combined with Mendelian randomization(MR).METHODS:Initially,20497 subjects from the complete questionnaire cycle in the NHANES database from 2005 to 2008 were included.By exclusion criteria,8460 subjects were screened with 1676 myopia samples and 6784 control samples.Subsequently,baseline characteristics,association analyses,risk stratification analyses,and receive operating characteristic curve(ROC)were used to investigate the associations between covariates and myopia.Then,the causal relationship was explored in depth by MR analysis,and was estimated the reliability by sensitivity analyses and directionality tests.RESULTS:Baseline characteristics illustrated a significant difference between myopia and controls for both asthma and covariates(excluding gender;P<0.05).The results in all three models indicated that asthma was strongly associated with myopia and the effect on myopia was not significantly confounded by other covariates[model 3:odd ratio(OR)=1.31;95%CI=1.07-1.62;P=0.0133].The risk stratification analysis again verified that asthma remained strongly associated with myopia and was a risk factor for myopia(P<0.05,OR>1).ROC proved that the model was accurate in its prediction[area under curve(AUC)=0.7].Subsequently,the causal relationship between them was statistically significant(P<0.05)according to the inverse variance weighted(IVW)method in MR.Scatterplot showed that asthma and myopia had significant positive causality and were not affected by confounders.Forest plot displayed an increasing risk of myopia on asthma(OR>1).The funnel plot demonstrated compliance with Mendel’s second law.Sensitivity analysis and directional analysis further confirmed the confidence of the MR analysis results and a unidirectional causal relationship between them.CONCLUSION:A significant association and causality between asthma and myopia is found through the NHANES database and MR analysis,which is important implications for public health policy development and clinical practice. 展开更多
关键词 ASTHMA MYOPIA National Health and Nutrition Examination Survey Mendelian randomization
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Lifestyle behaviors,serum metabolites and high myopia:Mendelian randomization and mediation analysis
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作者 Nian-En Liu Xiao-Tong Xu Xiao-Bing Yu 《International Journal of Ophthalmology(English edition)》 2026年第1期140-148,共9页
AIM:To explore the causal relationship between several possible behavioral factors and high myopia(HM)using multivariable Mendelian randomization(MVMR)approach and to find the mediators among them with mediation analy... AIM:To explore the causal relationship between several possible behavioral factors and high myopia(HM)using multivariable Mendelian randomization(MVMR)approach and to find the mediators among them with mediation analysis.METHODS:The causal effects of several behavioral factors,including screen time,education time,time spent outdoors,and physical activity,on the risk of HM using univariable Mendelian randomization(MR)and MVMR analyses were first assessed.Genome-wide association study summary statistics of serum metabolites were also used in mediation analysis to determine the extent to which serum metabolites mediate the effects of behavioral factors on HM.RESULTS:MR analyses indicated that both increased time spent outdoors and a higher frequency of moderate physical activity significantly reduced the risk of HM.Further MVMR analysis confirmed that moderate physical activity independently contributed to a lower risk of HM.Additionally,MR analyses identified 13 serum metabolites significantly associated with HM,of which 12 were lipids and one was an amino acid derivative.Mediation analysis revealed that six lipid metabolites mediated the protective effects of moderate physical activity on HM,with the highest mediation proportion observed for 1-(1-enyl-palmitoyl)-GPC(p-16:0;30.83%).CONCLUSION:This study suggests that in addition to outdoor time,moderate physical activity habits may have an independent protective effect against HM and pointed to lipid metabolites as priority targets for the prevention due to low physical activity.These results emphasize the importance of physical activity and metabolic health in HM and underscore the need for further study of these complex associations. 展开更多
关键词 high myopia physical activity serum metabolites multivariable Mendelian randomization mediation analysis
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Evaluation of spatial variability characteristics based on anisotropic modes of random fields
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作者 Kejing Chen Qinghui Jiang 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第1期494-508,共15页
This paper introduces a framework for modeling random fields,with a particular emphasis on analyzing anisotropic spatial variability.It establishes a clear connection between the correlation function and the Kriging v... This paper introduces a framework for modeling random fields,with a particular emphasis on analyzing anisotropic spatial variability.It establishes a clear connection between the correlation function and the Kriging variogram across various anisotropic modes,providing mathematical models to enhance our understanding of random fields.A new anisotropy index,called LSAI,is introduced to quantify anisotropy based on the autocorrelation length and the orientation of the principal axes within the variogram.An LSAI value closer to one indicates a lower degree of anisotropy.The present study examines how the degree of anisotropy varies with different autocorrelation lengths and angles between the principal axes,providing valuable insights into these relationships.To improve the accuracy of parameter probability distribution estimations,this study integrates limited field test data using a Bayesian inference approach.Additionally,the Markov chain Monte Carlo simulation method is employed to develop a conditional random field(CRF)for the deformation modulus.By incorporating data from field bearing plate tests,the posterior variance data for the deformation modulus are derived.This process facilitates the construction of a detailed and reliable CRF for the deformation modulus. 展开更多
关键词 Conditional random field(CRF) Anisotropic mode KRIGING Bayesian method VARIOGRAM
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Variable Selection and Parameter Estimation in Distributed High-Dimensional Quantile Regression with Responses Missing at Random
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作者 CHEN Dan CHEN Ruijing +1 位作者 TANG Jiarui LI Huimin 《Journal of Systems Science & Complexity》 2026年第1期385-409,共25页
Quantile regression(QR)has become an important tool to measure dependence of response variable's quantiles on a number of predictors for heterogeneous data,especially heavy-tailed data and outliers.However,it is q... Quantile regression(QR)has become an important tool to measure dependence of response variable's quantiles on a number of predictors for heterogeneous data,especially heavy-tailed data and outliers.However,it is quite challenging to make statistical inference on distributed high-dimensional QR with missing data due to the distributed nature,sparsity and missingness of data and nondifferentiable quantile loss function.To overcome the challenge,this paper develops a communicationefficient method to select variables and estimate parameters by utilizing a smooth function to approximate the non-differentiable quantile loss function and incorporating the idea of the inverse probability weighting and the penalty function.The proposed approach has three merits.First,it is both computationally and communicationally efficient because only the first-and second-order information of the approximate objective function are communicated at each iteration.Second,the proposed estimators possess the oracle property after a limited number of iterations without constraint on the number of machines.Third,the proposed method simultaneously selects variables and estimates parameters within a distributed framework,ensuring robustness to the specified response probability or propensity score function of the missing data mechanism.Simulation studies and a real example are used to illustrate the effectiveness of the proposed methodologies. 展开更多
关键词 Distributed estimator high-dimensional model missing at random quantile regression variable selection
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