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Adenocarcinoma originating from a colonic duplication cyst: A case report
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作者 Jeehye Lee Jung Wook Suh 《World Journal of Gastrointestinal Surgery》 2025年第4期405-411,共7页
BACKGROUND Gastrointestinal duplication is a rare congenital anomaly of the digestive tract,with colonic manifestations being particularly uncommon.Malignant transformation of colonic duplication cysts is rare,with ad... BACKGROUND Gastrointestinal duplication is a rare congenital anomaly of the digestive tract,with colonic manifestations being particularly uncommon.Malignant transformation of colonic duplication cysts is rare,with adenocarcinoma being the most frequently reported type.Herein,we report a rare case of adenocarcinoma originating from a colonic duplication cyst.CASE SUMMARY A 49-year-old woman was found to have an elevated cancer antigen 19-9 level during a routine checkup.Imaging revealed a well-defined abdominal cavity cystic mass,which was initially suspected to be an ovarian teratoma.Laparoscopic surgery revealed a duplication cyst,and pathological examination confirmed adenocarcinoma arising from the cyst.The mass within the transverse mesocolon was successfully excised by a colorectal surgeon.Immunohistochemical analysis confirmed adenocarcinoma with invasion into the muscularis propria.Postoperative endoscopy and positron emission computed tomography scan showed no signs of malignancy,except for an elevated cancer antigen 19-9 level.A multidisciplinary team recommended no further chemotherapy,advising routine follow-up for monitoring.CONCLUSION Colonic duplications,though rare,remain a differential diagnosis of unexplained abdominal masses,with complete resection being their primary treatment approach. 展开更多
关键词 Gastrointestinal duplication Colonic duplication Surgical resection ADENOCARCINOMA Malignant transformation Case report
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Subtotal resection of gastric duplication cysts using endoscopic submucosal dissection: A case report
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作者 Ning Zhu Meng-Yao Chen +5 位作者 Ke-Qing Li Yuan-Miao Zhang Fang-Lan Li Peng Li Jie Wu Bai-Cang Zou 《World Journal of Gastrointestinal Surgery》 2025年第10期428-433,共6页
BACKGROUND Gastric duplication cysts(GDCs)are rare congenital anomalies,and consensus guidelines for their diagnosis and management are currently lacking.We report a rare case of a GDC in a female child presenting as ... BACKGROUND Gastric duplication cysts(GDCs)are rare congenital anomalies,and consensus guidelines for their diagnosis and management are currently lacking.We report a rare case of a GDC in a female child presenting as a submucosal tumor in the gastric antrum.Subtotal resection was achieved using endoscopic submucosal dissection(ESD),resulting in complete symptom relief and pathological confirmation.This case demonstrates the therapeutic potential of ESD for intraluminal GDCs and underscores the importance of complete resection for definitive diagnosis.CASE SUMMARY A 12-year-old girl presented with abdominal distension and pain for>1 year.Gastroscopy revealed a protruding lesion approximately 30 mm in diameter in the gastric antrum.Superficial biopsies revealed moderate chronic inflammation and intestinal metaplasia.Contrast-enhanced computed tomography showed a mass protruding into the gastric lumen with homogeneous cyst wall enhancement.Endoscopic ultrasonography identified a hypoechoic mass originating from the muscularis mucosa.The patient underwent ESD for diagnosis and symptom relief.Intraoperatively,due to firm adhesion between the cyst base and the muscularis propria,selective preservation of the adherent cyst base was performed to mitigate perforation and stenosis risks.Histopathology confirmed a GDC,with cyst lumen lined by gastric-type columnar epithelium and an outer smooth muscle layer.Focal ectopic pancreatic tissues were identified.The patient recovered without complications and remained asymptomatic during 6-month follow-up.Repeat gastroscopy showed the residual cyst wall conforming to antral mucosa,with no recurrence.CONCLUSION Subtotal resection of GDCs using ESD demonstrates a favorable prognosis. 展开更多
关键词 Gastric duplication cysts Endoscopic submucosal dissection Endoscopic ultrasound Subtotal resection Case report
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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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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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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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A Robust Image Encryption Method Based on the Randomness Properties of DNA Nucleotides
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作者 Bassam Al-Shargabi Mohammed Abbas Fadhil Al-Husainy +1 位作者 Abdelrahman Abuarqoub Omar Albahbouh Aldabbas 《Computers, Materials & Continua》 2026年第4期391-415,共25页
The advent of 5G technology has significantly enhanced the transmission of images over networks,expanding data accessibility and exposure across various applications in digital technology and social media.Consequently... The advent of 5G technology has significantly enhanced the transmission of images over networks,expanding data accessibility and exposure across various applications in digital technology and social media.Consequently,the protection of sensitive data has become increasingly critical.Regardless of the complexity of the encryption algorithm used,a robust and highly secure encryption key is essential,with randomness and key space being crucial factors.This paper proposes a new Robust Deoxyribonucleic Acid(RDNA)nucleotide-based encryption method.The RDNA encryption method leverages the unique properties of DNA nucleotides,including their inherent randomness and extensive key space,to generate a highly secure encryption key.By employing transposition and substitution operations,the RDNA method ensures significant diffusion and confusion in the encrypted images.Additionally,it utilises a pseudorandom generation technique based on the random sequence of nucleotides in the DNA secret key.The performance of the RDNA encryption method is evaluated through various statistical and visual tests,and compared against established encryption methods such as 3DES,AES,and a DNA-based method.Experimental results demonstrate that the RDNA encryption method outperforms its rivals in the literature,and achieves superior performance in terms of information entropy,avalanche effect,encryption execution time,and correlation reduction,while maintaining competitive values for NMAE,PSNR,NPCR,and UACI.The high degree of randomness and sensitivity to key changes inherent in the RDNA method offers enhanced security,making it highly resistant to brute force and differential attacks. 展开更多
关键词 Security analysis image protection randomness in cryptography DNA nucleotides DNA-based encryption
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Evaluation of the susceptibility to landslide geological disasters based on different slope units and an information content random forest model:a case study of the Longhua District,Shenzhen
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作者 XIONG Haoyu RAN Xiangjin XUE Linfu 《Global Geology》 2026年第1期86-100,共15页
Slope units are divided according to the real topography and have clear geological characteristics,making them ideal units for evaluating the susceptibility to geological disasters.Based on the results of automaticall... Slope units are divided according to the real topography and have clear geological characteristics,making them ideal units for evaluating the susceptibility to geological disasters.Based on the results of automatically and manually corrected hydrological slope unit division,the Longhua District,Shenzhen City,Guangdong Province,was selected as the study area.A total of 15 influencing factors,namely Fluctuation,slope,slope aspect,curvature,topographic witness index(TWI),stream power index(SPI),topographic roughness index(TRI),annual average rainfall,distance to water system,engineering rock group,distance to fault,land use,normalized difference vegetation index(NDVI),nighttime light,and distance to road,were selected as evaluation indicators.The information volume model(IV)and random points were used to select non-geological disaster units,and then the random forest model(RF)was used to evaluate the susceptibility to geological disasters.The automatic slope unit and the hydrological slope unit were compared and analyzed in the random forest and information volume random forest models.The results show that the area under the curve(AUC)values of the automatic slope unit evaluation results are 0.931 for the IV-RF model and 0.716 for the RF model,which are 0.6%(IV-RF model)and 1.9%(RF model)higher than those for the hydrological slope unit.Based on a comparison of the evaluation methods based on the two types of slope units,the hydrological slope unit evaluation method based on manual correction is highly subjective,is complicated to operate,and has a low evaluation accuracy,whereas the evaluation method based on automatic slope unit division is efficient and accurate,is suitable for large-scale efficient geological disaster evaluation,and can better deal with the problem of geological disaster susceptibility evaluation. 展开更多
关键词 geological hazards slope unit information content random forest model susceptibility assessment SHENZHEN
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Quantifying secondary organic aerosols and O_(3) formation drivers in North China:Comprehensive method combining random forest,positive matrix factorization,and observation-based model
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作者 Qi Huang Tianshuai Li +7 位作者 Tao Zhang Yuan Fang Feijie Gong Yifan Li Peng Xu Tianqi Zhang Lingxiao Yang Wenxing Wang 《Journal of Environmental Sciences》 2026年第2期1-12,共12页
Although the concentration of fine particulate matter(PM_(2.5))is reducing continuously,the proportion of secondary organic aerosols(SOA)in PM_(2.5) and the O_(3) levels are increasing.This is causing severe complex a... Although the concentration of fine particulate matter(PM_(2.5))is reducing continuously,the proportion of secondary organic aerosols(SOA)in PM_(2.5) and the O_(3) levels are increasing.This is causing severe complex atmospheric pollution in North China.It is essential to identify and quantify the driving factors of SOA and O_(3),including the various pollution sources and meteorological factors.PM_(2.5) and volatile organic compounds(VOCs)samples were collected simultaneously in three cities in Shandong Province during different pollution scenarios from 2021 to 2023.Then,the carbonaceous aerosol and 99 VOC species were analyzed.Random forest(RF)combined with positive matrix factorization and an observation-based model(OBM)were used to quantify the key drivers of SOA and O_(3).Aromatic hydrocarbons were the main contributors to secondary organic aerosol potential(74.3%-89.9%),whereas alkenes contributed the most to the ozone formation potential(27.0%-62.3%).The RF modeling identified temperature and NOx as the dominant drivers of ozone formation.These accounted for 47.8%and 17.4%,respectively.Temperature showed a positive correlation with O_(3) because an increase in temperature can promote ozone formation.NOx had a significant negative correlation with O_(3),which was consistent with the conclusions from the sensitivity analysis of the OBM.The dominant contributors to SOA were vehicle emissions,solvent use,and industrial emissions.These accounted for 43.9%,18.2%,and 10.5%,respectively.An evident positive correlation existed between these emission sources and SOA. 展开更多
关键词 Volatile organic compounds Ozone formation Secondary organic aerosol Observation-based model random forest
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