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基于区间毕达哥拉斯犹豫模糊熵和交叉熵的ELECTRE II决策方法
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作者 杨威 李静 《工程数学学报》 CSCD 北大核心 2024年第3期525-539,共15页
针对属性权重完全未知或部分已知,属性值为区间毕达哥拉斯犹豫模糊数的多属性决策问题,提出了基于区间毕达哥拉斯犹豫模糊熵和交叉熵的ELECTRE II法。首先给出区间毕达哥拉斯犹豫模糊数的区间形式的得分函数和精度函数,定义新的距离测... 针对属性权重完全未知或部分已知,属性值为区间毕达哥拉斯犹豫模糊数的多属性决策问题,提出了基于区间毕达哥拉斯犹豫模糊熵和交叉熵的ELECTRE II法。首先给出区间毕达哥拉斯犹豫模糊数的区间形式的得分函数和精度函数,定义新的距离测度。然后基于区间毕达哥拉斯犹豫模糊数的模糊因子、直觉因子和幅度因子,给出熵和交叉熵公式,并证明其性质,提出了基于熵和交叉熵确定属性权重的方法。最后提出了区间毕达哥拉斯犹豫模糊环境下的改进的ELECTRE II法,利用综合优势值对方案进行排序,并通过算例和比较分析验证了该方法的可行性和有效性。 展开更多
关键词 多属性决策 区间毕达哥拉斯犹豫模糊集 交叉熵 ELECTRE ii
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基于改进NSGA-II的轨道交通接驳公交线路优化 被引量:1
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作者 裴玉龙 姜封帅 +1 位作者 王婉佼 何庆龄 《重庆交通大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第6期54-63,共10页
为解决接驳公交线路规划不合理和时间安排不完善的问题,提出了基于改进NSGA-II算法的环形接驳公交线路优化方法。首先,结合双层规划理论,以乘客出行时间成本最小化、公交企业运营收益和接驳公交服务率最大化为目标函数,以接驳公交线路... 为解决接驳公交线路规划不合理和时间安排不完善的问题,提出了基于改进NSGA-II算法的环形接驳公交线路优化方法。首先,结合双层规划理论,以乘客出行时间成本最小化、公交企业运营收益和接驳公交服务率最大化为目标函数,以接驳公交线路站点数、线路长度和发车频率作为约束条件构建上层模型,采用Logit模型构建了下层接驳客流分配模型;其次,运用Floyd算法对NSGA-II算法的初始化种群进行了优化,针对所提出的模型设计了模型求解流程;最后,以哈尔滨市轨道交通1号线医大一院轨道交通站为案例,运用笔者提出的多目标双层规划模型和算法进行求解,并与原NSGA-II算法和基于Logistic混沌映射的NSGA-II算法进行对比。研究结果表明:基于Floyd算法改进的NSGA-II算法在多目标双层规划模型求解时,收敛速度更快效果更好,求解结果可以在Pareto前沿得到多个相互非支配的最优解;不同解集对应目标函数值不同,但可以达到接驳公交网络整体效益最优,采用折衷最优解集表述求解结果。 展开更多
关键词 交通工程 城市公交 多目标优化 双层规划 NSGA-ii
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融合NSGA-II和CSA的多目标车间调度
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作者 杨青 席珍珍 +2 位作者 葛亮 林星宇 邢志超 《计算机工程与应用》 CSCD 北大核心 2024年第4期315-323,共9页
针对在灵活车间系统中调度作业和自动引导车(automated guide vehicle,AGV)的同时调度问题,考虑在有限多个AGV和加工机台的情况下,以最小化最大完工时间、单个AGV搬运消耗时间及所有AGV搬运总消耗时间为目标函数,设计融合NSGA-II(non-do... 针对在灵活车间系统中调度作业和自动引导车(automated guide vehicle,AGV)的同时调度问题,考虑在有限多个AGV和加工机台的情况下,以最小化最大完工时间、单个AGV搬运消耗时间及所有AGV搬运总消耗时间为目标函数,设计融合NSGA-II(non-dominated sorting genetic algorithms)和克隆选择(clonal selection algorithm,CSA)的改进算法INGCSA来解决此类问题。采用工件、加工机台和AGV三部分编码;引入非支配排序和目标函数值大小排序后总得分进行种群分层,从而有效地保留优秀个体;针对克隆后的种群,对不同等级的种群采取不同的变异概率,并对染色体进行内部交换与均匀交叉混合交换的基因重组,有效地提高了种群的多样性与防止陷入局部最优。通过三组对比实验,验证了该算法在探索最优解时,具有运行时间短、稳定性高和收敛性好等优点。 展开更多
关键词 NSGA-ii 克隆选择算法 任务调度 运输调度 自动引导车(AGV)
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营心宁胶囊辅助治疗对冠心病心力衰竭患者血管紧张肽II水平和心功能的影响
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作者 王静 李燕妮 《临床医学进展》 2024年第1期1135-1140,共6页
目的:观察营心宁胶囊辅助治疗对冠心病心力衰竭患者血管紧张肽II (AngII)水平和心功能的影响。方法:将128例患者分为两组,对照组64例,治疗组64例。对照组予常规治疗,治疗组患者在此基础上加用营心宁胶囊治疗,每次4粒,每日3次。治疗前及... 目的:观察营心宁胶囊辅助治疗对冠心病心力衰竭患者血管紧张肽II (AngII)水平和心功能的影响。方法:将128例患者分为两组,对照组64例,治疗组64例。对照组予常规治疗,治疗组患者在此基础上加用营心宁胶囊治疗,每次4粒,每日3次。治疗前及治疗8周后检测血浆AngII、脑钠肽(BNP),并行心脏彩色多普勒超声心动图测定左室射血分数(LVEF)、左室舒张末期内径(LVEDD)和每搏输出量(SV)。结果:治疗组和对照组总有效率分别为92.2%和89.1% (P > 0.01);显效率分别为43.8%,32.8% (P < 0.01)。两组治疗后患者的AngII、BNP、LVEF、LVEDD和SV均较治疗前明显改善(P < 0.01或P < 0.05),且治疗组患者的改善水平优于对照组(P < 0.01)。结论:营心宁胶囊能有效降低患者AngII水平,并对心功能有改善作用。 展开更多
关键词 营心宁 冠状动脉粥样硬化性心脏病心力衰竭 血管紧张肽ii 心功能
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血管紧张素II对脓毒症休克大鼠心脏功能的影响
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作者 安辉 姜檀 李晓伟 《中文科技期刊数据库(文摘版)医药卫生》 2024年第4期0182-0185,共4页
本研究拟通过盲肠结扎穿孔制备大鼠脓毒症模型,观察血管紧张素II对脓毒症休克(sepsis-shock)大鼠心脏功能的影响。方法 48只(Sprague-Dawley,SD)雄性大鼠随机分为6组(n=8):对照(control)组、假手术(sham)组、脓毒症休克(SS)组、去甲肾... 本研究拟通过盲肠结扎穿孔制备大鼠脓毒症模型,观察血管紧张素II对脓毒症休克(sepsis-shock)大鼠心脏功能的影响。方法 48只(Sprague-Dawley,SD)雄性大鼠随机分为6组(n=8):对照(control)组、假手术(sham)组、脓毒症休克(SS)组、去甲肾上腺素(NE)治疗组、血管紧张素II (ANGII)治疗组。采用盲肠结扎穿孔制备脓毒症休克动物模型。监测大鼠心率、血压变化。监测过程中大鼠如出现平均动脉压下降至65mmHg以下,立即给予0.9%生理盐水进行液体复苏,观察10分钟后如效果不佳,按照分组给予不同血管活性药物泵入。分别在造模后6,12,18,24小时抽血行心肌酶学指标检测,同时在该时段行超声观察大鼠心脏超声检查。于术后24小时留取心脏组织进行氧化因子指标测定,并进行心脏组织病理学观察。结果 与对照组和假手术组对比,脓毒症休克、去甲肾上腺素组、血管紧张素组平均动脉压下降明显,液体复苏效果欠佳,需要血管活性药物干预。与对照组和假手术组对比,脓毒症休克、去甲肾上腺素组、血管紧张素II组炎症反应、乳酸指标明显升高,具有统计学差异(P<0.05)。脓毒症休克组与对照组、假手术组相比,心脏左室射血分数(LVEF)明显下降,具有统计学差异(P<0.05),应用血管活性药物后,左室射血分数明显提高,血管紧张素II组射血分数提高与脓毒症组相比,具有显著统计学差异(P<0.01)。脓毒症休克组与对照组、假手术组相比,心肌酶学指标明显升高,应用去甲肾上腺素或血管紧张素II干预后,心肌酶学指标下降,与脓毒症组相比,具有统计学差异(P<0.05),血管紧张素II组改善更为明显(P<0.01)。结论 血管紧张素II可改善脓毒症休克对大鼠的心肌损害,对脓毒症休克大鼠心肌有一定的保护作用。 展开更多
关键词 脓毒症休克 去甲肾上腺素 血管紧张素ii 心脏功能
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表达Strep-tag II的重组塞内卡病毒的构建与鉴定
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作者 史家宝 蒙靓 +4 位作者 肖培宇 范峻豪 安同庆 王海伟 于力 《中国预防兽医学报》 CAS CSCD 北大核心 2024年第2期140-146,共7页
为构建表达Strep-tag II的重组塞内卡病毒(SVA),本研究在感染性cDNA克隆p SVA-I212V/S460L的基础上,采用重叠延伸PCR扩增Strep-tag II并采用无缝克隆法将其插入SVA VP1基因C端,构建感染性cDNA克隆,命名为p SVA-Strep,并采用双酶切和测... 为构建表达Strep-tag II的重组塞内卡病毒(SVA),本研究在感染性cDNA克隆p SVA-I212V/S460L的基础上,采用重叠延伸PCR扩增Strep-tag II并采用无缝克隆法将其插入SVA VP1基因C端,构建感染性cDNA克隆,命名为p SVA-Strep,并采用双酶切和测序鉴定正确后,将p SVA-Strep转染BHK-21细胞拯救重组病毒,收集病变细胞上清,并将含有病毒的细胞上清和野生型SVA(SVA-WT)分别感染BHK-21细胞,以未感染病毒的BHK-21细胞作为阴性对照,感染后24 h分别以鼠源SVA VP2蛋白单克隆抗体(MAb)5D10(1∶1000)、鼠源Strep-tag II MAb(1∶2000)作为一抗,以FITC标记的山羊抗小鼠Ig G(1∶2000)为二抗,采用间接免疫荧光试验(IFA)对重组病毒鉴定。IFA结果显示,以鼠源SVA VP2蛋白MAb 5D10为一抗,SVA-WT和重组病毒感染的细胞均出现绿色荧光,以Strep-tag II MAb作为一抗时,仅有重组病毒感染的细胞出现绿色荧光,经SVA-WT感染的BHK-21细胞及阴性对照细胞均无绿色荧光,表明拯救了Strep-tag II标记的重组病毒,并将其命名为r SVA-Strep。将r SVA-Strep在BHK-21细胞中连续传10代,每隔2代采用引物VP1-F/R经PCR鉴定并对第10代重组病毒的VP1基因测序以鉴定r SVA-Strep的遗传稳定性。结果显示,每隔两代的重组病毒经PCR扩增后均出现约780 bp的目的条带,第10代重组病毒扩增的VP1基因测序结果显示Strep-tag II基因仍在重组病毒中,且无基因突变,表明r SVA-Strep的遗传稳定性较强;将SVA-WT和r SVA-Strep分别以MOI 0.01感染BHK-21细胞,在感染后4 h、8 h、12 h、24 h、36 h、48 h和72 h收获病毒测定病毒滴度并绘制生长曲线,结果显示在病毒感染36 h内r SVA-Strep和SVA-WT生长动力学基本一致,表明Strep-tag II的引入在病毒感染36 h内对SVA的复制基本无影响。采用0.2%甲醛充分灭活r SVA-Strep,并利用Strep-TactinRXT Purification纯化试剂盒纯化该灭活病毒,将r SVA-Strep灭活病毒上清加至Strep-Tactin亲和层析柱,分别用不同体积洗脱缓冲液依次洗脱病毒并通过western blot鉴定病毒的纯化效果。对纯化过程中不同洗脱液洗脱病毒的western blot结果显示,不同体积的洗脱液中E1、E2和E3均出现VP0和VP2两条带,且E1和E2的条带最明显,表明洗脱缓冲液的最佳洗脱体积约为2.2 CV;以上结果表明r SVA-Strep可通过Strep-Tactin亲和层析柱一步法纯化。本研究在SVA中插入Strep-tag II标签,为SVA灭活疫苗的快速纯化提供技术手段,也为其他病原的快速纯化方法的建立提供参考。 展开更多
关键词 塞内卡病毒 Strep-tag ii 感染性克隆 抗原纯化
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基于NSGA-II遗传算法的定轴注射模具成型工艺参数优化
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作者 陈超 高全杰 《农业装备与车辆工程》 2024年第8期153-157,共5页
为解决注射成型过程中铸件的质量和铸造效率低等问题,提出一种NSGA-II算法和TOPSIS方法与响应面法相结合的新型注射工艺参数优化筛选方法。以定轴为研究对象,采用Box-Behnken设计,以熔体温度、模具温度、注射时间、保压压力为变量,以翘... 为解决注射成型过程中铸件的质量和铸造效率低等问题,提出一种NSGA-II算法和TOPSIS方法与响应面法相结合的新型注射工艺参数优化筛选方法。以定轴为研究对象,采用Box-Behnken设计,以熔体温度、模具温度、注射时间、保压压力为变量,以翘曲变形量和体积收缩率为响应变量,采用NSGA-II遗传算法对2个响应的目标函数执行优化,用TOPSIS方法求解优化得到的Pareto前沿解集,找到最优解。仿真结果表明,当注射时间为40.71s、模具温度为131℃、熔体温度为180.07℃、保压压力为65 MPa时,翘曲变形降低了10.92%、体积收缩率降低了11.19%。优化后的注射工艺参数可有效消除铸件内部收缩松动和缩孔缺陷,形成性能良好的致密铸件,提高了产品质量。 展开更多
关键词 注射成型 多目标优化 BOX-BEHNKEN设计 NSGA-ii遗传算法
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Fe(II)改性蒙脱石对土壤汞的吸附固定机理探究
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作者 周细霞 刘朝淑 孙荣国 《贵州师范大学学报(自然科学版)》 CAS 北大核心 2024年第4期63-74,共12页
为明确Fe-MMT对土壤汞离子(Hg^(2+))的吸附、解吸特性及潜在作用机理,采用FeSO_(4)·7H_(2)O改性钠基蒙脱土(Na-MMT),合成了Fe(II)基蒙脱石(Fe-MMT),并探究了不同pH值、吸附剂用量、Hg^(2+)初始浓度和反应时间等条件下,Fe-MMT对土壤... 为明确Fe-MMT对土壤汞离子(Hg^(2+))的吸附、解吸特性及潜在作用机理,采用FeSO_(4)·7H_(2)O改性钠基蒙脱土(Na-MMT),合成了Fe(II)基蒙脱石(Fe-MMT),并探究了不同pH值、吸附剂用量、Hg^(2+)初始浓度和反应时间等条件下,Fe-MMT对土壤Hg^(2+)的吸附解吸特性、吸附动力学和等温吸附模型。结果发现:在pH=5、吸附剂用量为0.5 g、Hg^(2+)初始浓度为170 mg/L、反应时间为0.5 h的条件下,Fe-MMT对土壤Hg^(2+)的去除率高达76.8%;Fe-MMT对Hg^(2+)+的吸附过程符合Langmuir等温吸附模型,伪二阶动力学模型可较好地拟合吸附动力学行为,表明该吸附过程主要为单分子层吸附,且主要发生在吸附剂表面的均相反应位点上;结合微观结构表征,发现Fe-MMT对土壤Hg^(2+)的吸附主要通过-S^(2-)、-SH和-OH与Hg^(2+)进行络合,以及Fe^(2+)与Hg^(2+)的原位共沉淀络合引起的;Fe-MMT在水-土混合体系中的解吸率为9.7%,表明Fe-MMT对土壤Hg^(2+)具有较强的固定作用。可见,Fe-MMT具有修复Hg污染土壤的潜力。 展开更多
关键词 吸附 水土混合 解吸 Fe(ii)改性蒙脱石(Fe-MMT)
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成人低角型安氏II类1分类与安氏II类2分类错合畸形矫治前唇颏形态差异性研究
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作者 吴金枝 姜荻 +1 位作者 蒋均红 刘新庆 《中文科技期刊数据库(文摘版)医药卫生》 2024年第10期0116-0119,共4页
通过对比成人低角型安氏II类1分类和安氏II类2分类错合畸形患者的面部形态特点及唇颏形态,为临床制定矫治方案和临床治疗工作提供思路。方法 分别选取低角型安氏I类1分类和安氏II类2分类错合畸形患者40例,男女比例为1:1,年龄:18-25岁.... 通过对比成人低角型安氏II类1分类和安氏II类2分类错合畸形患者的面部形态特点及唇颏形态,为临床制定矫治方案和临床治疗工作提供思路。方法 分别选取低角型安氏I类1分类和安氏II类2分类错合畸形患者40例,男女比例为1:1,年龄:18-25岁.通过将侧貌X线片和面部90°面相重合,对测量面部软组织21项指标进行测量。结果 上唇突点—E线距离,下唇突点—E线距离,上唇倾角,下唇倾角,上唇厚度,上下唇面积对比均有统计学意义(P<0.05)。结论 低角型安氏II类1分类与安氏II类2分类相比,上下唇均呈前突状,上唇面积,安氏II类1分类较安氏II类2分类小,下唇面积,安氏II类1分类较安氏II类2分类大。 展开更多
关键词 低角型 安氏ii类1分类 安氏ii类2分类 唇颏形态
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Downregulation of Serum PTEN Expression in Mercury-Exposed Population and PI3K/AKT Pathway-Induced Inflammation 被引量:1
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作者 MEI Peng DING En Min +6 位作者 YIN Hao Yang DING Xue Xue WANG Huan WANG Jian Feng HAN Lei ZHANG Heng Dong ZHU Bao Li 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第4期354-366,共13页
Objective This study investigated the impact of occupational mercury(Hg) exposure on human gene transcription and expression, and its potential biological mechanisms.Methods Differentially expressed genes related to H... Objective This study investigated the impact of occupational mercury(Hg) exposure on human gene transcription and expression, and its potential biological mechanisms.Methods Differentially expressed genes related to Hg exposure were identified and validated using gene expression microarray analysis and extended validation. Hg-exposed cell models and PTEN lowexpression models were established in vitro using 293T cells. PTEN gene expression was assessed using qRT-PCR, and Western blotting was used to measure PTEN, AKT, and PI3K protein levels. IL-6 expression was determined by ELISA.Results Combined findings from gene expression microarray analysis, bioinformatics, and population expansion validation indicated significant downregulation of the PTEN gene in the high-concentration Hg exposure group. In the Hg-exposed cell model(25 and 10 μmol/L), a significant decrease in PTEN expression was observed, accompanied by a significant increase in PI3K, AKT, and IL-6 expression.Similarly, a low-expression cell model demonstrated that PTEN gene knockdown led to a significant decrease in PTEN protein expression and a substantial increase in PI3K, AKT, and IL-6 levels.Conclusion This is the first study to report that Hg exposure downregulates the PTEN gene, activates the PI3K/AKT regulatory pathway, and increases the expression of inflammatory factors, ultimately resulting in kidney inflammation. 展开更多
关键词 PTEN Occupational mercury exposure Occupational health PI3K/AKT pathway 293T cell IL-6
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青霜露暴露治疗II度烧烫伤临床观察
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作者 陈建彬 丁祖章 +3 位作者 陈骏 宋红梅 刘莹莹 胡娟 《外科(汉斯)》 2024年第3期55-61,共7页
目的:观察青霜露暴露治疗烧烫伤的临床效果。方法:门诊II度烧烫伤患者100例,其中浅II度67例,深II度33例。以暴露疗法在烧烫伤创面青霜露局部用药,每日1~3次,直至愈合。结果:67例浅II度烧烫伤创面经青霜露治疗全部愈合,愈合时间最短6天,... 目的:观察青霜露暴露治疗烧烫伤的临床效果。方法:门诊II度烧烫伤患者100例,其中浅II度67例,深II度33例。以暴露疗法在烧烫伤创面青霜露局部用药,每日1~3次,直至愈合。结果:67例浅II度烧烫伤创面经青霜露治疗全部愈合,愈合时间最短6天,最长30天;33例深II度烧烫伤创面经青霜露治疗30天痊愈31例,显效2例,愈合时间最短14天。所有创面愈合良好,局部疼痛消失和无明显增生性瘢痕。结论:青霜露治疗烧烫伤促进创面愈合,疗效确切;本方法简单方便,值得临床推广应用。 展开更多
关键词 青霜露 暴露疗法 ii度烧烫伤 临床观察
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Hybrid treatment of varied orthodontic appliances for a patient with skeletal class II and temporomandibular joint disorders:A case report and review of literature 被引量:1
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作者 Tong Lu Li Mei +2 位作者 Bao-Chao Li Zi-Wei Huang Huang Li 《World Journal of Clinical Cases》 SCIE 2024年第2期431-442,共12页
BACKGROUND The relation between orthodontic treatment and temporomandibular disorders(TMDs)is under debate;the management of TMD during orthodontic treatment has always been a challenge.If TMD symptoms occur during or... BACKGROUND The relation between orthodontic treatment and temporomandibular disorders(TMDs)is under debate;the management of TMD during orthodontic treatment has always been a challenge.If TMD symptoms occur during orthodontic treatment,an immediate pause of orthodontic adjustments is recommended;the treatment can resume when the symptoms are managed and stabilized.CASE SUMMARY This case report presents a patient(26-year-old,female)with angle class I,skeletal class II and TMDs.The treatment was a hybrid of clear aligners,fixed appliances and temporary anchorage devices(TADs).After 3 mo resting and treatment on her TMD,the patient’s TMD symptom alleviated,but her anterior occlusion displayed deep overbite.Therefore,the fixed appliances with TAD were used to correct the anterior deep-bite and level maxillary and mandibular deep curves.After the levelling,the patient showed dual bite with centric relation and maximum intercuspation discrepancy on her occlusion.After careful examination of temporomandibular joints(TMJ)position,the stable bite splint and Invisible Mandibular Advancement appliance were used to reconstruct her occlusion.Eventually,the improved facial appearance and relatively stable occlusion were achieved.The 1-year follow-up records showed there was no obvious change in TMJ morphology,and her occlusion was stable.CONCLUSION TMD screening and monitoring is of great clinical importance in the TMD susceptible patients.Hybrid treatment with clear aligners and fixed appliances and TADs is an effective treatment modality for the complex cases. 展开更多
关键词 Temporomandibular disorder Skeletal class ii Deep overbite Dual bite Invisible mandibular advancement appliance Case report
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血管活性药物评分联合APACHE II评分对血流感染后脓毒性休克患者预后的预测价值
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作者 王佳权 姚莉 赵晶晶 《临床医学进展》 2024年第2期3114-3121,共8页
目的:探讨血管活性药物评分(vasoactive inotropic score, VIS)联合急性生理与慢性健康评分(APACHE II)对血流感染后脓毒性休克患者结局的预测价值,为临床提供参考。方法:采用回顾性研究方法,通过收集2020年1月至2022年12月安徽医科大... 目的:探讨血管活性药物评分(vasoactive inotropic score, VIS)联合急性生理与慢性健康评分(APACHE II)对血流感染后脓毒性休克患者结局的预测价值,为临床提供参考。方法:采用回顾性研究方法,通过收集2020年1月至2022年12月安徽医科大学附属合肥医院重症医学科收治的185例脓毒性休克患者的临床资料,根据28 d转归情况,分为存活组95例和死亡组90例,记录所有患者性别、年龄、相关血液检测指标、SOFA评分、24小时内急性生理与慢性健康评分(APACHE II)及24小时内最大血管活性药物评分(VISmax24)等信息,采用单因素分析筛选脓毒性休克患者的相关危险因素,多因素logistic回归分析影响脓毒性休克患者预后的独立危险因素,采用受试者工作特征(receiver op-erating characteristic, ROC)曲线下面积(area under curve, AUC)分析各指标的诊断价值。结果:单因素分析结果表明:死亡组的APACHE II评分(24.30 ± 5.157)、VISmax24 [100.0 (53.5, 121.0)]明显高于存活组(P max24联合APACHE II评分(AUC = 0.848, 95% CI: 0.792~0.905),较单一的APACHE II评分(AUC = 0.729, 95% CI: 0.655~0.802)、VISmax24 (AUC = 0.783, 95% CI: 0.709~0.856)、乳酸(AUC = 0.665, 95% CI: 0.587~0.743)、SOFA (AUC = 0.680, 95% CI: 0.602~0.758)预测价值更高。结论:VISmax24联合APACHE II评分能更有效预测血流感染后脓毒性休克患者的预后。 展开更多
关键词 血管活性药物评分 脓毒性休克 APACHE ii评分 病死率 预测价值
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Mercury Levels Assessment in the Population of Aby and Frambo Villages in the Vinicity of Aby Lagoon in Côte d’Ivoire (West Africa)
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作者 Stéphane Jean Claon Serge Kouakou Kouassi +4 位作者 Nina Laurette Ahouéfa Laurent Kipré Seri Arsène M’bassidjé Seka Joseph Allico Djaman Luc Kouakou Kouadio 《Journal of Water Resource and Protection》 CAS 2024年第3期219-232,共14页
The Minamata Convention in the aim to protect human life and the environment, seeks to reduce mercury (Hg) by monitoring it concentrations in the environment. Artisanal and Small-scale Gold Mining (ASGM) has been iden... The Minamata Convention in the aim to protect human life and the environment, seeks to reduce mercury (Hg) by monitoring it concentrations in the environment. Artisanal and Small-scale Gold Mining (ASGM) has been identified as the most important anthropogenic source of human exposure to Hg. In this context, the main goal of this study was to assess the level of mercury in hair of two (2) populations living along two lagoons respectively Aby and Tendo, in Ivory Coast. To reach this goal, hair samples of 138 residents were collected and analyzed by using Cold Vapor Atomic Fluorescence Spectrophotometry (CV-AFS) technique for mercury concentration. Results showed that for the entire population the Hg mean was 2.34 μg/g. Also, they were ranged between 0.15 to 8.53 μg/g and presented substantial differences amongst the villages. In Aby village, we observed the highest Hg concentrations (Mean = 2.62 μg/g). Our findings showed that almost the entire sample group (82%) exceed the USEPA recommended limit, furthermore 56% of them exceed the normal level of WHO and 2% of the respondent has the unhealthy levels of mercury (≥6 μg Hg/g) of hair by WHO standards. Gender differences in hair mercury varies greatly among reports. Lower levels in women’s hair compared to men were reported in the both village. Considering age, the lowest concentrations were observed with children. However, when we take in account the age groups, data suggested that the most exposed sub-population of [18-29] years old is from Aby village in opposite at Frambo village, the same case those who were ≥ 40 years old. It’s convenient to note that, the proportion of Mercury levels would not to be neglected among studied population especially with the resident from Aby village. So, some measures need to be taken at the political level to control mercury contamination. 展开更多
关键词 mercury HAIR ASGM Population Exposure Côte d’Ivoire
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Key issues on magnetic reconnection at Mercury
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作者 Jun Zhong 《Earth and Planetary Physics》 EI CAS CSCD 2024年第5期673-685,共13页
Magnetic reconnection processes and their impact on planetary magnetospheric dynamics exhibit significant differences due to differences in upstream solar wind conditions and internal planetary environments.Current un... Magnetic reconnection processes and their impact on planetary magnetospheric dynamics exhibit significant differences due to differences in upstream solar wind conditions and internal planetary environments.Current understanding of reconnection phenomena at Mercury is rooted in the MESSENGER mission.However,direct detection of reconnection remains rare.Here,we aim to assess the limitations of MESSENGER in detecting reconnection in Mercury’s space and to discuss key issues of reconnection that will be addressed by BepiColombo,including the dynamics of magnetic flux ropes,particle acceleration,density asymmetric reconnection,IMF-driven near-tail structures,and potential modes of magnetospheric convection. 展开更多
关键词 magnetic reconnection mercury MESSENGER BEPICOLOMBO
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Statistical study of magnetic holes in the upstream region of Mercury’s bow shock
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作者 GuoQiang Wang SuDong Xiao +2 位作者 MingYu Wu YuanQiang Chen TieLong Zhang 《Earth and Planetary Physics》 EI CAS CSCD 2024年第2期326-337,共12页
Magnetic holes are magnetic depression structures that exist widely in many plasma environments.The magnetic holes with durations of>1 s in the solar wind at Mercury’s orbit have drawn much attention,but the prope... Magnetic holes are magnetic depression structures that exist widely in many plasma environments.The magnetic holes with durations of>1 s in the solar wind at Mercury’s orbit have drawn much attention,but the properties of the magnetic holes with shorter durations are still unclear.Here,we investigate the magnetic holes with durations of 0.1-100 s in the upstream region of Mercury’s bow shock based on observations by the MESSENGER(MErcury Surface,Space ENvironment,GEochemistry,and Ranging)spacecraft.They can be divided into two groups according to the distribution of their duration:small-duration magnetic holes(SDMHs,<0.6 s)and large-duration magnetic holes(LDMHs,>0.6 s).The duration of each group approximately obeys a log-normal distribution with a median of~0.25 s and 3 s,respectively.Approximately 1.7%(32.6%)of the SDMHs(LDMHs)reduce the magnetic field strength by more than 50%.For both groups,some structures have a linear or quasi-linear polarization,whereas others have an elliptical polarization.The magnetic hole events in both groups tend to have a higher rate of occurrence when the interplanetary magnetic field strength is weaker.Their occurrence rates are also affected by Mercury’s foreshock,which can increase(decrease)the occurrence rate of the SDMHs(LDMHs).This finding suggests that Mercury’s foreshock might be one source of the SDMHs and that the foreshock can destroy some LDMHs.These observations suggest that a new group of magnetic holes with durations of<0.6 s exist in the upstream region of Mercury’s bow shock. 展开更多
关键词 magnetic hole solar wind mercury FORESHOCK
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Tb^(3+)-nucleic acid probe-based label-free and rapid detection of mercury pollution in food
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作者 Xuhan Xia Chenxi Zhou +7 位作者 Yulin Zhu Yi Dong Qiang He Mohammad Rizwan Khan Yuanlong Chi Rosa Busquets Ruijie Deng Yao Ren 《Food Science and Human Wellness》 SCIE CSCD 2024年第2期993-998,共6页
Mercury is a threatening pollutant in food,herein,we developed a Tb^(3+)-nucleic acid probe-based label-free assay for mix-and-read,rapid detection of mercury pollution.The assay utilized the feature of light-up fluor... Mercury is a threatening pollutant in food,herein,we developed a Tb^(3+)-nucleic acid probe-based label-free assay for mix-and-read,rapid detection of mercury pollution.The assay utilized the feature of light-up fluorescence of terbium ions(Tb^(3+))via binding with single-strand DNA.Mercury ion,Hg^(2+)induced thymine(T)-rich DNA strand to form a double-strand structure(T-Hg^(2+)-T),thus leading to fluorescence reduction.Based on the principle,Hg^(2+)can be quantified based on the fluorescence of Tb^(3+),the limit of detection was 0.0689μmol/L and the linear range was 0.1-6.0μmol/L.Due to the specificity of T-Hg^(2+)-T artificial base pair,the assay could distinguish Hg^(2+)from other metal ions.The recovery rate was ranged in 98.71%-101.34%for detecting mercury pollution in three food samples.The assay is low-cost,separation-free and mix-to-read,thus was a competitive tool for detection of mercury pollution to ensure food safety. 展开更多
关键词 mercury pollution Food safety Nucleic acid probe LABEL-FREE TERBIUM
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2-萘甲酸/1,10-菲啰啉共同构筑Mn(II)配合物的合成及固态发光
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作者 任娜娜 江旭滢 +3 位作者 宋合兴 史福林 王雅茹 孙赞 《人工晶体学报》 CAS 北大核心 2024年第10期1776-1783,共8页
在溶剂热条件下,以2-萘甲酸(HL)与1,10-菲啰啉(phen)为配体、碳酸锰为金属源合成了一例双核锰配合物[Mn_(2)(L)_(4)(phen)_(2)(H_(2)O)_(2)](1)。通过单晶X射线衍射、元素分析、傅里叶变换红外光谱、粉末X射线衍射和热重分析等对配合物... 在溶剂热条件下,以2-萘甲酸(HL)与1,10-菲啰啉(phen)为配体、碳酸锰为金属源合成了一例双核锰配合物[Mn_(2)(L)_(4)(phen)_(2)(H_(2)O)_(2)](1)。通过单晶X射线衍射、元素分析、傅里叶变换红外光谱、粉末X射线衍射和热重分析等对配合物1进行结构表征。单晶衍射分析表明配合物1属于三斜晶系,P1空间群,晶胞参数为a=0.76989(5)nm,b=1.17586(5)nm,c=1.66830(9)nm,α=107.074(5)°,β=96.167(5)°,γ=106.901(5)°。不对称单元由一个锰离子、两个2-萘甲酸根、一个1,10-菲啰啉和一个水分子组成,Mn(II)呈扭曲的八面体构型。两个不对称单元之间通过羧基氧原子桥接形成双核分子,双核结构之间通过π…π堆积作用形成2D超分子结构。荧光光谱分析结果表明:配合物1具有良好的荧光性能,最大发射波长为416 nm(λ_(ex)=302 nm)。热重分析表明配合物1能够稳定到117℃,之后开始失水(失水量为3.18%),脱水之后的结构能稳定到223℃,之后有机骨架开始坍塌。Hirshfeld表面分析研究了分子间的相互作用。 展开更多
关键词 双核Mn(ii)配合物 溶剂热合成 晶体结构 2-萘甲酸 荧光性质 表面分析
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Rational Synthesis of Crystalline Covalent Triazine Framework with Methylthio Pendant Arms for Efficient Mercury(Ⅱ)Adsorption
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作者 LOU Yi-xiao ZHOU Lu-lu +1 位作者 YANG Na ZHU Xiang 《分子催化(中英文)》 CAS CSCD 北大核心 2024年第4期309-316,共8页
The interest in curtailing environmental pollution issues through physical separation processes has inspired an extensive search for novel nanoporous materials with exceptional adsorption capabilities.Covalent triazin... The interest in curtailing environmental pollution issues through physical separation processes has inspired an extensive search for novel nanoporous materials with exceptional adsorption capabilities.Covalent triazine frameworks(CTFs),emerged as a class of crystalline covalent organic frameworks(COFs),have been widely examined for various separation applications,owing to their large porosity,high stability,and rich nitrogen(N)doping.The development of CTFs for efficient adsorption of mercury(Ⅱ)(Hg^(2+))is of great importance for the field,whereas it is rarely attempted,on account of limited synthetic strategies and unknown structural-property relations of conventional CTFs derived from ionothermal approaches.Herein,we report rational synthesis of a crystalline CTF with methylthio pendant arms for efficient removal of Hg^(2+)with an exceptional capacity of 751 mg·g^(-1),ranking at the top among previously-reported adsorbents.This work may open up new possibility in the synthesis of COFs for various separations. 展开更多
关键词 CTFs methylthio pendant arms mercury adsorption structural-property relationship
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Physiological Mechanism of Exogenous Selenium in Alleviating Mercury Stress on Pakchoi(Brassica campestris L.)
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作者 Chengxu Qian Qiangwen Chen +4 位作者 Leiyu Jiang Xiaoyan Yang Shen Rao Weiwei Zhang Feng Xu 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第5期951-962,共12页
The objective of this study was to explain the physiological mechanisms through which Na_(2)SeO_(3) mitigates the growth and developmental inhibition of pakchoi under HgCl_(2)stress.The results showed that treatment w... The objective of this study was to explain the physiological mechanisms through which Na_(2)SeO_(3) mitigates the growth and developmental inhibition of pakchoi under HgCl_(2)stress.The results showed that treatment with HgCl_(2)(40 mg L^(−1))led to reduced biomass,dwarfing,root shortening,and root tip necrosis in pakchoi.Compared to control(CK),the activities of superoxide dismutase(SOD)and peroxidase(POD)in Hg treatment increased,and the content of malondialdehyde(MDA)also dramatically increased,which negatively impacted the growth of pakchoi.Low concentrations of Na_(2)SeO_(3)(0.2 mg L^(−1))significantly increased the content of soluble sugars compared with control,while chlorophyll,soluble proteins,free amino acids,and vitamin C had no significant changes.The results of the mixed treatments with HgCl_(2)and Na_(2)SeO_(3) suggested that selenium may be able to reduce the toxicity of mercury in pakchoi.The biomass,plant height,root length,chlorophyll content,soluble protein,other physiological indicators,and proline showed significant increases compared with the HgCl_(2)treatment.Additionally,the MDA content and mercury accumulation in pakchoi decreased.Our results revealed the antagonistic effects of selenium and mercury in pakchoi.Thus,a theoretical basis for studying pakchoi’s mercuryexcreted and selenium-rich cultivation technology was provided. 展开更多
关键词 SELENIUM mercury stress PAKCHOI physiological properties antioxidant enzymes
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