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牙槽骨微穿孔术用于中重度牙列拥挤伴前牙唇倾患者正畸治疗中的美学效果分析

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中国医疗美容 2024年第5期14卷 80-83页

作者：张凌云段秀敏韩韶丰李鹏举正畸科河南安阳455000

目的探讨分析牙槽骨微穿孔术用于中重度牙列拥挤伴前牙唇倾患者正畸治疗中的美学效果。方法于2020年8月~2023年8月期间,选取我院中重度牙列拥挤伴前牙唇倾患者97例,均接受牙槽骨微穿孔术治疗,观察其治疗情况及美学效果。结果加力1个月... 详细信息

目的探讨分析牙槽骨微穿孔术用于中重度牙列拥挤伴前牙唇倾患者正畸治疗中的美学效果。方法于2020年8月~2023年8月期间,选取我院中重度牙列拥挤伴前牙唇倾患者97例,均接受牙槽骨微穿孔术治疗,观察其治疗情况及美学效果。结果加力1个月后尖牙移动距离为(1.93±0.25)mm,牙根吸收量为(0.48±0.16)mm;加力2个月后尖牙移动距离为(3.69±0.47)mm,牙根吸收量为(0.57±0.19)mm。矫治后患者U1-NA距、U1-NA角低于矫治前,U1-L1高于矫治前(P<0.05)。矫治后红色美学指数(PES)评分为(10.27±1.68)分,高于矫治前(13.16±0.59)分(P<0.05)。患者对正畸治疗结果的满意度为97.94%。结论牙槽骨微穿孔术用于中重度牙列拥挤伴前牙唇倾患者正畸治疗中可促进正畸牙移动速度,提高矫治效果,且不会明显增加患者牙根吸收量,患者满意度高。

关键词：牙槽骨微穿孔术牙列拥挤前牙唇倾正畸美学效果

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微塑料与重金属交互对土壤生物的毒性研究

广州化工 2024年第14期52卷 78-81页

作者：谢雨婷蒋志雯蒋雯雯张芸菱程征铭刘佳张亮南京师范大学泰州学院化学与生物工程学院江苏泰州225300

微塑料(Microplastics,MPs)是一种新兴的环境污染物,具有潜在生态毒性效应,在土壤中与多种重金属存在复合污染。评价微塑料对土壤植物、动物和微生物的危害时,考虑微塑料与重金属的协同污染至关重要。本文综述了微塑料和重金属的来源、... 详细信息

微塑料(Microplastics,MPs)是一种新兴的环境污染物,具有潜在生态毒性效应,在土壤中与多种重金属存在复合污染。评价微塑料对土壤植物、动物和微生物的危害时,考虑微塑料与重金属的协同污染至关重要。本文综述了微塑料和重金属的来源、分布、生态毒性及其交互作用对土壤生物的毒性效应,探究两者交互作用对土壤生态环境和农业发展的影响。最后基于此展望微塑料未来的研究方向,以期为促进土壤生态系统保护和农业可持续发展提供理论参考。

关键词：微塑料重金属交互作用土壤生物毒性效应

Dynamic recrystallization mechanism, texture evolution development and mechanical characteristics of a Mg–8.7Gd–4.18Y–0.42Zr magnesium alloy by ECAP

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Progress in Natural Science:Materials International 2024年第2期34卷 376-388页

作者： ling zhang Yinglong Li School of Materials Science and Engineering Northeastern University School of Mechanical and Engineering Ningxia Institute of Science and Technology

Equal channel angle pressing is recognized for its ability to refine alloy grains and alter grain orientation, thereby achieve better mechanical performance of the magnesium alloy. This study investigates the microstructures,dynamic recrystallization mechanism, texture development, and mechanical performance of GW94K(Mg–8.7Gd–4.18Y–0.42Zr wt. %) Mg alloy following ECAP-4 passes at 400°C and 3 mm/min. Results show that when high-temperature deformation is undertaken, twin formation is suppressed while dislocation slip is facilitated, increasing dislocation density during deformation. Following ECAP deformation, the sample displayed higher fracture elongation, TYS, and UTS than the as-solutioned GW94K alloy. In particular, the GW94K alloy performed well mechanically after ECAP-4 passes, with an ultimate TYS of 231 MPa, an UTS of 290 MPa, and an elongation of 14.8 %. DDRX and shear bands induce CDRX, both of which are important in plastic deformation. as well as in modifying microstructure and grain orientation during ECAP deformation.

关键词： Dynamic recrystallization mechanism Equal channel angular pressing Magnesium alloy Mechanical performance Mg-Gd-Y-Zr alloy Texture development

Bayesian network-based survival prediction model for patients having undergone post-transjugular intrahepatic portosystemic shunt for portal hypertension

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World Journal of Gastroenterology 2024年第13期30卷 1859-1870页

作者： Rong Chen ling Luo yun-Zhi zhang Zhen Liu An-Lin Liu Yi-Wen zhang Department of Infectious Diseases Second Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China

BACKGROUND Portal hypertension(PHT),primarily induced by cirrhosis,manifests severe symptoms impacting patient *** transjugular intrahepatic portosystemic shunt(TIPS)is a critical intervention for managing PHT,it carries risks like hepatic encephalopathy,thus affecting patient survival *** our knowledge,existing prognostic models for post-TIPS survival in patients with PHT fail to account for the interplay among and collective impact of various prognostic factors on ***,the development of an innovative modeling approach is essential to address this *** To develop and validate a Bayesian network(BN)-based survival prediction model for patients with cirrhosis-induced PHT having undergone *** The clinical data of 393 patients with cirrhosis-induced PHT who underwent TIPS surgery at the Second Affiliated Hospital of Chongqing Medical University between January 2015 and May 2022 were retrospectively *** were selected using Cox and least absolute shrinkage and selection operator regression methods,and a BN-based model was established and evaluated to predict survival in patients having undergone TIPS surgery for *** Variable selection revealed the following as key factors impacting survival:age,ascites,hypertension,indications for TIPS,postoperative portal vein pressure(post-PVP),aspartate aminotransferase,alkaline phosphatase,total bilirubin,prealbumin,the Child-Pugh grade,and the model for end-stage liver disease(MELD)*** on the above-mentioned variables,a BN-based 2-year survival prognostic prediction model was constructed,which identified the following factors to be directly linked to the survival time:age,ascites,indications for TIPS,concurrent hypertension,post-PVP,the Child-Pugh grade,and the MELD *** Bayesian information criterion was 3589.04,and 10-fold cross-validation indicated an average log-likelihood loss of 5.55 with a standard deviation of *** model’s acc

关键词： Bayesian network Cirrhosis Portal hypertension Transjugular intrahepatic portosystemic shunt Survival prediction model

Value Iteration-Based Cooperative Adaptive Optimal Control for Multi-Player Differential Games With Incomplete Information

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IEEE/CAA Journal of Automatica Sinica 2024年第3期11卷 690-697页

作者： yun zhang Lulu zhang yunze Cai the Department of Automation Shanghai Jiao Tong UniversityShanghai 200240 the Key Laboratory of System Control and Information Processing Ministry of Education of ChinaShanghai 200240China

This paper presents a novel cooperative value iteration(VI)-based adaptive dynamic programming method for multi-player differential game models with a convergence *** players are divided into two groups in the learning process and adapt their policies *** method removes the dependence of admissible initial policies,which is one of the main drawbacks of the PI-based ***,this algorithm enables the players to adapt their control policies without full knowledge of others’ system parameters or control *** efficacy of our method is illustrated by three examples.

关键词： Adaptive dynamic programming incomplete information multi-player differential game value iteration

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致密碎屑岩储层评价方法研究

石油地球物理勘探 2008年第5期43卷 595-599,487-488页

作者：张凌云中国石化石油工程西南公司测井分公司四川成都610100

百色盆地东部拗陷中央凹陷带那读组为陆相碎屑岩沉积地层,储集层的特点是岩性致密,孔隙结构复杂,非均质性较强,横向可对比性较差,用传统解释方法对其储层进行正确评价比较困难。综合岩心分析、储层电性特征对该区储层进行系统研究,初步... 详细信息

百色盆地东部拗陷中央凹陷带那读组为陆相碎屑岩沉积地层,储集层的特点是岩性致密,孔隙结构复杂,非均质性较强,横向可对比性较差,用传统解释方法对其储层进行正确评价比较困难。综合岩心分析、储层电性特征对该区储层进行系统研究,初步形成了一套用常规测井资料综合评价致密碎屑岩储层评价技术,包括流体性质判别、孔隙结构评价、储层非均质性评价、储层分类、产量预测等方法,并通过实例进行了效果评价,证实该技术的应用可有效地促进中央凹陷带的勘探开发。

关键词：测井评价那读组碎屑岩致密非均质孔隙结构百色盆地

MODIFIED STOCHASTIC EXTRAGRADIENT METHODS FOR STOCHASTIC VARIATIONAL INEQUALITY

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Journal of Computational Mathematics 2024年第2期42卷 390-414页

作者： ling zhang lingling Xu School of Management and Economic Beijing Institute of TechnologyBeijing 100081China School of Mathematical Sciences Nanjing Normal UniversityNanjing 210023China School of Mathematical Sciences and Jiangsu Key Laboratory for NSLSCS Nanjing Normal UniversityNanjing 210023China

In this paper,we consider two kinds of extragradient methods to solve the pseudo-monotone stochastic variational inequality ***,we present the modified stochastic extragradient method with constant step-size(MSEGMC)and prove the convergence of *** the strong pseudo-monotone operator and the exponentially growing sample sequences,we establish the R-linear convergence rate in terms of the mean natural residual and the oracle complexity O(1/ǫ).Second,we propose a modified stochastic extragradient method with adaptive step-size(MSEGMA).In addition,the step-size of MSEGMA does not depend on the Lipschitz constant and without any line-search ***,we use some numerical experiments to verify the effectiveness of the two algorithms.

关键词： Stochastic variational inequality Pseudo-monotone Modified stochastic ex-tragradient methods Adaptive step-size

Quantifying peripapillary vessel density and retinal nerve fibre layer in type 1 diabetic children without clinically detectable retinopathy using OCTA

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International Journal of Ophthalmology(English edition) 2024年第2期17卷 278-281页

作者： ling Chen yun Feng Sha-Sha zhang Yan-Fang Liu Ping Lin Xi’an Children’s Hospital Affiliated to Xi’an Jiaotong University Xi’an 710002Shaanxi ProvinceChina

AIM:To quantify changes in radial peripapillary capillary vessel density(ppVD)and the peripapillary retinal nerve fiber layer(pRNFL)in children with type 1 diabetes without clinical diabetic retinopathy by optical coherence tomography angiography(OCTA),providing a basis for early retinopathy in children with type 1 ***:This was a retrospective study.A total of 30 patients(3–14y)with type 1 diabetes without clinical diabetic retinopathy(NDR group)were included.A total of 30 age-matched healthy subjects were included as the normal control group(CON group).The HbA1c level in the last 3mo was measured once in the NDR *** pRNFL thickness and ppVD were automatically measured,and the mean pRNFL and ppVD were calculated in the nasal,inferior,temporal,and superior *** changes in ppVD and pRNFL in the two groups were ***:Compared with CON group,the nasal and superior ppVDs decreased in the NDR group(all P0.05).Person and Spearman correlation analysis of ppVD and pRNFL thickness in each quadrant of the NDR group showed a positive correlation between nasal and superior(all P0.05).There was no significant correlation between the HbA1c level and ppVD and pRNFL in any quadrant(all P>0.05).There was no significant correlation between the course of diabetes mellitus and ppVD and pRNFL in any quadrant(all P>0.05).CONCLUSION:ppVD and pRNFL decrease in eyes of children with type 1 diabetes before clinically detectable retinopathy and OCTA is helpful for early monitoring.

关键词： diabetic retinopathy children peripapillary vessel density peripapillary retinal nerve fiber layer optical coherence tomography angiography

支持向量机在富氮含能离子盐撞击感度定量构效关系研究中的应用

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含能材料 2023年第5期31卷 448-456页

作者：张云苓白杨北京农业职业学院国际教育学院北京100012 北京理工大学化学与化工学院原子分子簇科学教育部重点实验室北京100081

为了研究富氮含能离子盐的撞击感度(IS)与分子结构的关系,在M06-2X/6-311++G(3df,3pd)理论水平下对21种含能离子盐进行了构型优化和量子化学参数计算,并以IS为目标值,以最高占据轨道能量(E_(HOMO))、最低空轨道能量(E_(LUMO))、偶极矩(... 详细信息

为了研究富氮含能离子盐的撞击感度(IS)与分子结构的关系,在M06-2X/6-311++G(3df,3pd)理论水平下对21种含能离子盐进行了构型优化和量子化学参数计算,并以IS为目标值,以最高占据轨道能量(E_(HOMO))、最低空轨道能量(E_(LUMO))、偶极矩(μ)、极化率(α)、氧平衡(OB)、核独立化学位移(NICS)、可利用自由体积(ΔV)、静电势方差(σ^(2))、电离势(I)和电子亲和势(A)作为描述符,采用主成分分析(PCA)方法结合支持向量机(SVM)回归算法,建立了相关性较好的构效关系(QSPR)模型(相关系数和均方根误差分别为0.98和0.11)。采用该模型对新设计的6种新型富氮含能离子盐的IS进行预测,发现其中基于氮(-5(-1氢-四唑-5-基)-2氢-1,2,3-三唑-4-基)-4-硝基-呋咱-3-胺(HTANFT)设计的三种含能离子盐的撞击感度(依次为18,17,35 J)比传统炸药TNT(15 J)还要钝感,表明基于HTANFT设计的三种含能离子盐是潜在的理想含能材料。

关键词：富氮含能离子盐撞击感度(IS) 定量构效关系(QSPR) 支持向量机(SVM) 主成分分析(PCA)