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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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Adaptor signature based on randomized EdDSA in blockchain 被引量:1
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作者 Yixing Zhu Huilin Li +1 位作者 Mengze Li Yong Yu 《Digital Communications and Networks》 2025年第3期689-699,共11页
Adaptor signature,a new primitive that alleviates the scalability issue of blockchain to some extent,has been widely adopted in the off-chain payment channel and atomic swap.As an extension of standard digital signatu... Adaptor signature,a new primitive that alleviates the scalability issue of blockchain to some extent,has been widely adopted in the off-chain payment channel and atomic swap.As an extension of standard digital signature,adaptor signature can bind the release of a complete digital signature with the exchange of a secret value.Existing constructions of adaptor signatures are mainly based on Schnorr or ECDSA signature algorithms,which suffer low signing efficiency and long signature length.In this paper,to address these issues,we propose a new construction of adaptor signature using randomized EdDSA,which has Schnorr-like structure with higher signing efficiency and shorter signature length.We prove the required security properties,including unforgeability,witness extractability and pre-signature adaptability,of the new adaptor signature scheme in the random oracle model.We conduct a comparative analysis with an ECDSA-based adaptor signature scheme to demonstrate the effectiveness and feasibility of our new proposal. 展开更多
关键词 blockchain Adaptor signature randomized EdDSA Payment channel
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Hyponormal Block Toeplitz Operators on the Weighted Bergman Space with Circulant Symbols
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作者 FU Guangyang ZHOU Jiang 《数学进展》 北大核心 2026年第1期183-191,共9页
In this paper,we present a necessary and sufficient condition for hyponormal block Toeplitz operators T on the vector-valued weighted Bergman space with symbolsΦ(z)=G^(*)(z)+F(z),where F(z)=∑^(N)_(i)=1 A_(i)z^(i)and... In this paper,we present a necessary and sufficient condition for hyponormal block Toeplitz operators T on the vector-valued weighted Bergman space with symbolsΦ(z)=G^(*)(z)+F(z),where F(z)=∑^(N)_(i)=1 A_(i)z^(i)and G(z)=∑^(N)_(i)=1 A_(−i)z^(i),A_(i)ae culants. 展开更多
关键词 block Toeplitz operator hyponormal weighted Bergman space CIRCULANT COMMUTATOR
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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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乳腺癌TOMO计划设计及Block的应用方式研究
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作者 姜亚洲 杨潍铭 +1 位作者 王俭 李舰波 《生物医学工程与临床》 2026年第2期168-173,共6页
目的利用螺旋断层放射治疗(TOMO)计划系统制定乳腺癌保乳术后放射治疗计划,比较Block不同设计方法和径照功能对靶区和危及器官(OAR)剂量的影响。方法选择2024年2月至2025年2月宁波明州医院左侧乳腺癌保乳术后放射治疗女性患者15例,年龄3... 目的利用螺旋断层放射治疗(TOMO)计划系统制定乳腺癌保乳术后放射治疗计划,比较Block不同设计方法和径照功能对靶区和危及器官(OAR)剂量的影响。方法选择2024年2月至2025年2月宁波明州医院左侧乳腺癌保乳术后放射治疗女性患者15例,年龄34~66岁,平均年龄52岁;经病理明确诊断为左侧乳腺癌,其中病理分期TNMⅠ期4例,TNMⅡ期11例。基于TOMO计划系统为每例患者制定3种TOMO计划,第一种计划设计过程中应用了半挡Direction Block(DB)模式,第二种计划应用全挡Complete Block(CB)模式,第三种应用螺旋断层径照射(TD)模式制作计划;比较3种计划的剂量参数,包括靶区的适形度指数(HI)、均匀度指数(CI)、平均剂量、最大剂量;肺、心脏、健侧乳腺及脊髓等OAR剂量差异。结果在靶区剂量方面,DB组和CB组均具有较优异的均匀性和适形性,对比TD组计划差异有统计学意义(CI:0.861±0.041 vs 0.741±0.047、0.871±0.041 vs 0.741±0.047;HI:1.036±0.006 vs 1.052±0.007、1.037±0.004 vs 1.052±0.007)(P<0.05);OAR剂量方面,CB组计划的左肺V_(5)、V_(20)、D_(mean)和心脏V_(10)、V_(20)、D_(mean)均明显优于其他两组,差异均有统计学意义(P<0.05)。比较脊髓的最大剂量(D_(max)),CB组和TD组相对DB组较低,差异有统计学意义[(1.47±1.48)Gy vs(8.66±2.89)Gy、(0.46±0.13)Gy vs(8.66±2.89)Gy](P<0.05)。TD组计划的右肺V_(5),右侧乳腺平均剂量优于DB、CB两组,差异均有统计学意义[V_(5):(0.36±0.48)%vs(17.32±3.47)%、(0.36±0.48)%vs(10.66±4.10)%;右侧乳腺平均剂量:(1.53±0.88)Gy vs(6.79±1.41)Gy、(1.53±0.88)Gy vs(4.89±0.99)Gy](P<0.05)。但TD组心脏V_(10)、V_(10)较DB组、CB组计划高[V_(10):(12.39±4.39)%vs(9.72±5.03)%、(12.39±4.39)%vs(5.09±1.13)%;V_(10):(6.68±4.17)%vs(2.35±1.38)%、(6.68±4.17)%vs(1.47±0.78)%]。时间方面,CB组治疗时间最长,与DB组、TD组差异均有统计学意义[(15.18±2.31)min vs(9.68±1.43)min、(15.18±2.31)min vs(9.88±3.15)min](P<0.05)。结论针对左侧乳腺癌的3种计划比较,DB相对无明显优势,CB的优势表现在能明显降低患侧肺和心脏、脊髓的受量,TD则对保护对侧肺、乳腺能起更好的效果,但CB治疗时间较长,TD靶区适形性均匀性较差,可根据患者实际情况选择计划方式。 展开更多
关键词 螺旋断层放射治疗 block 乳腺癌 剂量学 断层径照
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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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Enhancing the performance of AlGaN deep-ultraviolet laser diodes without an electron blocking layer by using a thin undoped Al_(0.8)Ga_(0.2)N strip layer structure
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作者 SANG Xi-en WANG Fang +1 位作者 LIU Jun-jie LIU Yu-huai 《中国光学(中英文)》 北大核心 2026年第2期421-433,共13页
AlGaN-based deep-ultraviolet(DUV)laser diodes(LDs)face performance challenges due to elec-tron leakage and poor hole injection which is often worsened by polarization effects from conventional elec-tron blocking layer... AlGaN-based deep-ultraviolet(DUV)laser diodes(LDs)face performance challenges due to elec-tron leakage and poor hole injection which is often worsened by polarization effects from conventional elec-tron blocking layers(EBLs).To overcome these limitations,we propose an EBL-free DUV LD design incor-porating a 1-nm undoped Al_(0.8)Ga_(0.2)N thin strip layer after the last quantum barrier.Using PICS3D simula-tions,we evaluate the optical and electrical characteristics.Results show a significant increase in effective electron barrier height(from 158.2 meV to 420.7 meV)and a reduction in hole barrier height(from 149.2 meV to 62.8 meV),which enhance hole injection and reduce electron leakage.The optimized structure(LD3)achieves a 14%increase in output power,improved slope efficiency(1.85 W/A),and lower threshold current.This design also reduces the quantum confined Stark effect and forms dual hole accumulation regions,im-proving recombination efficiency. 展开更多
关键词 ALGAN deep ultraviolet laser diodes undoped thin strip structure without an electron blocking layers
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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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A case report with the progression from atrial fibrillation to complete AV block, heart failure and electrical storm
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作者 Shi-Xing LI Xiang-Min SHI +1 位作者 Jian LI Chuang ZHANG 《Journal of Geriatric Cardiology》 2026年第1期65-68,共4页
When patients initially present with atrial fibrillation along with an enlarged heart and heart failure, followed by atrioventricular block, it's essential to consider genetic factors.^([1])Genetic testing can off... When patients initially present with atrial fibrillation along with an enlarged heart and heart failure, followed by atrioventricular block, it's essential to consider genetic factors.^([1])Genetic testing can offer crucial diagnostic evidence, aiding in prognosis assessment and the adoption of appropriate treatment strategies. 展开更多
关键词 heart failure atrial fibrillation enlarged heart atrioventricular block genetic factors genetic testing adoption appropriate treatment strategies complete av block prognosis assessment
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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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Engineering repairable nanoporous functional coatings on arbitrary substrates by manipulating phase behaviors of block copolymers
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作者 Jiemei Zhou Xiang Ying +3 位作者 Daiwen Li Mingjie Wei Xiangyue Ye Yong Wang 《Chinese Journal of Chemical Engineering》 2026年第1期36-46,共11页
Nanoporous polymers are extensively coated on various substrates to deliver optical,permselective,or other functions.However,it remains desired to fast produce uniform nanoporous polymer coatings on substrates with co... Nanoporous polymers are extensively coated on various substrates to deliver optical,permselective,or other functions.However,it remains desired to fast produce uniform nanoporous polymer coatings on substrates with complex surfaces.Herein,by manipulating the interactions between block copolymers and selective solvents,we prepare repairable nanoporous polymers on arbitrary substrates.This is realized by an extremely simple sequential coating process:sequential coating of block copolymers and their swelling agents on substrate surfaces.The swelling agents are comprised of two solvents that swell the constituent blocks of the copolymers to different degrees,rapidly producing polymer coatings with uniform,interconnected,sub-50 nm pores.This sequential coating process is able to conformally build nanoporous polymers on nonplanar substrates with large lateral sizes and complex surface features,and also to in situ repair defects arising during usages.We further demonstrate that the nanoporous coatings show excellent antireflective and membrane separation performances.This sequential coating process is dictated by polymer–solvent interactions,and is expected to find applications in diverse fields for its simplicity,adaptability,and the capability to produce well-defined nanoporosities. 展开更多
关键词 Nanoporous coating block copolymers Selective swelling Polymer-solvent interactions ANTIREFLECTION
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Engineering stimuli-responsive block copolymers for multimodal bioimaging
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作者 Lizhuang Zhong Ming Liu +3 位作者 Shilong Su Dongxin Zeng Jing Hu Zhiqian Guo 《Chinese Chemical Letters》 2026年第1期116-124,共9页
The diagnostic efficacy of contemporary bioimaging technologies remains constrained by inherent limitations of conventional imaging agents,including suboptimal sensitivity,off-target biodistribution,and inherent cytot... The diagnostic efficacy of contemporary bioimaging technologies remains constrained by inherent limitations of conventional imaging agents,including suboptimal sensitivity,off-target biodistribution,and inherent cytotoxicity.These limitations have catalyzed the development of intelligent stimuli-responsive block copolymers-based bioimaging agents,which was engineered to dynamically respond to endogenous biochemical cues(e.g.,p H gradients,redox potential,enzyme activity,hypoxia environment) or exogenous physical triggers(e.g.,photoirradiation,thermal gradients,ultrasound(US)/magnetic stimuli).Through spatiotemporally controlled structural transformations,stimuli-responsive block copolymers enable precise contrast targeting,activatable signal amplification,and theranostic integration,thereby substantially enhancing signal-to-noise ratios of bioimaging and diagnostic specificity.Hence,this mini-review systematically examines molecular engineering principles for designing p H-,redox-,enzyme-,light-,thermo-,and US/magnetic-responsive polymers,with emphasis on structure-property relationships governing imaging performance modulation.Furthermore,we critically analyze emerging strategies for optical imaging,US synergies,and magnetic resonance imaging(MRI).Multimodal bioimaging has also been elaborated,which could overcome the inherent trade-offs between resolution,penetration depth,and functional specificity in single-modal approaches.By elucidating mechanistic insights and translational challenges,this mini-review aims to establish a design framework of stimuli-responsive block copolymersbased for high fidelity bioimaging agents and accelerate their clinical translation in precise diagnosis and therapy. 展开更多
关键词 STIMULI-RESPONSIVE block copolymers Molecular engineering Multimodal bioimaging Diagnosis and therapy
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ResghostNet:Boosting GhostNet with Residual Connections and Adaptive-SE Blocks
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作者 Yuang Chen Yong Li +2 位作者 Fang Lin Shuhan Lv Jiaze Jiang 《Computers, Materials & Continua》 2026年第2期1524-1541,共18页
Aiming at the problem of potential information noise introduced during the generation of ghost feature maps in GhostNet,this paper proposes a novel lightweight neural network model called ResghostNet.This model constr... Aiming at the problem of potential information noise introduced during the generation of ghost feature maps in GhostNet,this paper proposes a novel lightweight neural network model called ResghostNet.This model constructs the Resghost Module by combining residual connections and Adaptive-SE Blocks,which enhances the quality of generated feature maps through direct propagation of original input information and selection of important channels before cheap operations.Specifically,ResghostNet introduces residual connections on the basis of the Ghost Module to optimize the information flow,and designs a weight self-attention mechanism combined with SE blocks to enhance feature expression capabilities in cheap operations.Experimental results on the ImageNet dataset show that,compared to GhostNet,ResghostNet achieves higher accuracy while reducing the number of parameters by 52%.Although the computational complexity increases,by optimizing the usage strategy of GPU cachememory,themodel’s inference speed becomes faster.The ResghostNet is optimized in terms of classification accuracy and the number of model parameters,and shows great potential in edge computing devices. 展开更多
关键词 Residual connections adaptive-SE blocks lightweight neural network GPU memory usage
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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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The Magic of Organocatalytic Synergism in Switchable Polymerization:One-pot Synthesis of Block Copolymers with Programmable Sequences and Compositions
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作者 Shuai-Shuai Zhu Mao-Ji Zhao +1 位作者 Ying-Jie Yuan Yong Wang 《Chinese Journal of Polymer Science》 2026年第1期68-78,I0010,共12页
Switchable polymerization is emerging as a powerful tool to construct block copolymers directly from mixtures of monomers.However,current achievements typically iterate between two polymerization cycles to afford prod... Switchable polymerization is emerging as a powerful tool to construct block copolymers directly from mixtures of monomers.However,current achievements typically iterate between two polymerization cycles to afford products with fixed sequences and compositions.Herein,we report the triethylborane/1,8-diazabicyclo[5.4.0]undec-7-ene(Et_3B/DBU)pair-mediated four-component switchable polymerization of propylene oxide(PO),CO_(2),phthalic anhydride(PA),and racemic lactide(rac-LA),which enables the on-demand synthesis of four different block copolymers,i.e.,poly(propylene phthalate)-b-polylactide(PPE-b-PLA),PPE-b-PLA-b-poly(propylene carbonate)(PPC),PPE-b-PPC-b-PLA,and PPE-b-PPCb-poly(propylene oxide)(PPO),through rationally modulating the Lewis pair(LP)ratio.Core to this protocol is that increasing the loading of Et_(3)B accelerates the ring-opening of PO while impeding the reactivity of rac-LA,thus allowing for fine-tuning of the thermodynamic and kinetic of the switchable polymerization.Therefore,the four polymerization cycles involving PO/PA ring-opening copolymerization(ROCOP),PO/CO_(2) ROCOP,rac-LA ring-opening polymerization(ROP),and PO ROP can be connected and discriminated in precisely programmed manners. 展开更多
关键词 Switchable polymerization Organic Lewis pair block copolymers Ring-opening copolymerization Multicomponent reaction
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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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