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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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基于改进NSGA-II的轨道交通接驳公交线路优化
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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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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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氧化石墨烯(GO)表面原位生长二硫化钼(MoS2)材料高效去除Hg(II)
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作者 吕佳彤 林海英 《中国科技期刊数据库 工业A》 2024年第5期0193-0196,共4页
Hg(II)指的是游离的Hg2+及其不稳定的络合物,是厌氧条件下微生物将其转化为毒性更大的甲基汞的主要形式。作为一种超毒性重金属,Hg(II)可对肾脏、肝脏、免疫系统、内分泌系统以及生殖系统造成不可逆的损伤。在此文章中,以氧化石墨烯(GO... Hg(II)指的是游离的Hg2+及其不稳定的络合物,是厌氧条件下微生物将其转化为毒性更大的甲基汞的主要形式。作为一种超毒性重金属,Hg(II)可对肾脏、肝脏、免疫系统、内分泌系统以及生殖系统造成不可逆的损伤。在此文章中,以氧化石墨烯(GO)为基底,以L-半胱氨酸、钼酸铵、聚乙烯吡咯烷酮(PVP)、葡萄糖为原料,利用水热法于氧化石墨烯(GO)表面原位生长二硫化钼(MoS2)制备GO改性材料(MoS2/GO)。通过扫描电子显微镜(SEM)和x射线光电子能谱(XPS)表征得到MoS2/GO为石墨烯表面原位生长的层状放射性花状结构,对Hg(II)有较好的吸附作用且吸附后MoS2/GO有明显形态变化。MoS2/GO在较宽pH范围内对Hg(II)均有良好的吸附能力,拟二级动力学模型可以更好的描述该吸附过程,这证明MoS2/GO对Hg(II)之间的结合主要为化学作用。Freundlich模型可以很好的描述Hg(II)的吸附行为为多层吸附,PVP作为插层剂起到了一定的作用,25℃下MoS2/GO对Hg(II)的最大吸附容量为868.38 mg/g。该材料原料毒性小、MoS2层间距相对较大,对Hg(II)有着更为优异的去除能力,可较好的应用在含Hg废水处理中。 展开更多
关键词 氧化石墨烯 二硫化钼 插层剂 Hg(ii)吸附 环境
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Influence of Angiotensin II on α1-Adrenergic Receptors Function in Rat Aorta and Expression in Vascular Smooth Muscle Cells
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作者 Itzell Alejandrina Gallardo-Ortíz Juan Pablo de Jesús Benítez-Garrido +3 位作者 Santiago C. Sigrist-Flores Juan Javier López-Guerrero Enrique Hong Rafael Villalobos-Molina 《Journal of Biosciences and Medicines》 2024年第4期123-134,共12页
Angiotensin II (Ang II) is the main mediator of the Renin-Angiotensin-System acting on AT<sub>1</sub> and other AT receptors. It is regarded as a pleiotropic agent that induces many actions, including func... Angiotensin II (Ang II) is the main mediator of the Renin-Angiotensin-System acting on AT<sub>1</sub> and other AT receptors. It is regarded as a pleiotropic agent that induces many actions, including functioning as a growth factor, and as a contractile hormone, among others. The aim of this work was to examine the impact of Ang II on the expression and function of α<sub>1</sub>-adrenergic receptors (α<sub>1</sub>-ARs) in cultured rat aorta, and aorta-derived smooth muscle cells. Isolated Wistar rat aorta was incubated for 24 h in DMEM at 37˚C, then subjected to isometric tension and to the action of added norepinephrine, in concentration-response curves. Ang II was added (1 × 10<sup>−5</sup> M), and in some experiments, 5-Methylurapidil (α<sub>1A</sub>-AR antagonist), AH11110A (α<sub>1B</sub>-AR antagonist), or BMY-7378 (α<sub>1D</sub>-AR antagonist), were used to identify the α<sub>1</sub>-AR involved in the response. Desensitization of the contractile response to norepinephrine was observed due to incubation time, and by the Ang II action. α<sub>1D</sub>-AR was protected from desensitization by BMY-7378;while RS-100329 and prazosin partially mitigated desensitization. In another set of experiments, isolated aorta-derived smooth muscle cells were exposed to Ang II and α<sub>1</sub>-ARs proteins were evaluated. α<sub>1D</sub>-AR increased at 30 and 60 min post Ang II exposure, the α<sub>1A</sub>-AR diminished from 1 to 4 h, while α<sub>1B</sub>-AR remained unchanged over 24 h of Ang II exposure. Ang II induced an increase of α<sub>1D</sub>-AR at short times, and BMY-7378 protected α<sub>1D</sub>-AR from desensitization. 展开更多
关键词 Angiotensin ii α1D-AR α1-AR Expression Rat aorta Smooth Muscle Cells
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Case Report: Carnitine Palmitoyl Transferase II (CPT II) Deficiency
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作者 Kathy Po Marius Chivu +1 位作者 Edwin Rosas Balpreet Kaur 《Open Journal of Internal Medicine》 2024年第1期93-101,共9页
Carnitine Palmitoyl Transferase II (CPTII) is a very important enzyme that helps with the oxidation of long-chain fatty acid to produce energy. Deficiency in CPTII will lead to energy deficiency in the case of fasting... Carnitine Palmitoyl Transferase II (CPTII) is a very important enzyme that helps with the oxidation of long-chain fatty acid to produce energy. Deficiency in CPTII will lead to energy deficiency in the case of fasting and the accumulation of the long chain fatty in the body. There are three types of CPT II deficiency, the myopathic form, the severe infantile hepatocardiomuscular form and the lethal neonatal form. They are all inherited as an autosomal recessive. Diagnosis of the CPTII are 1) tandem mass spectrometry (MS/MS) in adult form and 2) CPTII polymorphism (F352C), which is linked to reducing the activity of CPTII in infantile form [1]. Glucose is the primary management and medium-chain fatty acid is an alternative due to the bypass of the CPTII enzyme in the pathway. For the prevention of CPTII deficiency are to avoid long chain fatty acid (C12-fatty acid), fasting, prolonged exercise, known triggers, and certain medications such as anti-epileptics and general anesthesia. During the rhabdomyolysis and myoglobinuria attack, it is very important to maintain hydration to avoid acute renal failure. If, however, renal failure occurs, dialysis is recommended. We present a case of a 27-year-old African American woman with the significant past medical history of CPT II deficiency leading to recurrent rhabdomyolysis and myoglobinuria. Together with all the research studies from diagnosis to treatment of CPTII deficiency will help in clinical management of patients. And this case report will add to the existing case reports of patients who have CPTII deficiency in terms of how we diagnose, how we treat, and how we prevent symptoms from re-occurring. 展开更多
关键词 Carnitine Palmitoyl Transferase ii (CPTii) Mitochondria Long Chain Fatty Acid Medium Chain Fatty Acid CARNITINE Carnitine Palmitoyl Transferase I (CPTI) Acyl-Carnitine BETA-OXIDATION RHABDOMYOLYSIS Myoglobinuria Renal Failure Hypoketotic Hypoglycemia
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基于改进NSGA-II算法的装配式建筑施工调度优化 被引量:2
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作者 汪和平 龚星霖 李艳 《工业工程》 北大核心 2023年第2期85-92,共8页
针对以往装配式建筑调度研究主要基于每项活动只有确定的活动时间和一种执行模式,而实际调度过程中存在不确定的活动时间和多种执行模式,建立多目标多模式资源约束下的模糊工期调度模型,提出一种改进的非支配排序遗传算法(INSGA-II)来求... 针对以往装配式建筑调度研究主要基于每项活动只有确定的活动时间和一种执行模式,而实际调度过程中存在不确定的活动时间和多种执行模式,建立多目标多模式资源约束下的模糊工期调度模型,提出一种改进的非支配排序遗传算法(INSGA-II)来求解(时间−成本)双目标优化模型。该算法根据活动的优先级关系进行种群初始化和交叉操作,同时提出新的包含活动列表、模式列表和资源列表的3段编码。最后,通过装配式建筑施工现场实际案例分析和算法性能对比,证明本文构建的调度模型和算法设计能有效地解决多模式资源约束下的模糊工期调度模型,为施工调度计划的设计提供科学的思路和方法。 展开更多
关键词 资源约束项目调度问题 装配式建筑施工 INSGA-ii算法 多目标优化
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微波消解-金纳米星比色法快速检测婴幼儿食品中的Co(II)
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作者 王永存 王素燕 《中国乳品工业》 CAS 北大核心 2023年第10期60-64,共5页
文章建立了一种利用金纳米星粒子(GNSs)作为探针快速检测婴幼儿食品中Co(II)含量的方法,首先使用微波消解对检测样品进行前处理,然后基于钴离子引发类芬顿反应刻蚀GNSs导致粒子形貌及溶液发生改变的原理,通过比色法实现了对婴幼儿食品中... 文章建立了一种利用金纳米星粒子(GNSs)作为探针快速检测婴幼儿食品中Co(II)含量的方法,首先使用微波消解对检测样品进行前处理,然后基于钴离子引发类芬顿反应刻蚀GNSs导致粒子形貌及溶液发生改变的原理,通过比色法实现了对婴幼儿食品中Co(II)的高灵敏检测。结果表明:Co(II)浓度在100 pmol/L~20μmol/L范围内与GNSs溶液的局部表面等离子体共振峰(LSPR)吸收峰的波长差Δλ具有良好的线性关系(R2=0.995),对婴幼儿食品样品中Co(II)含量检测表现出良好的重现性和准确性(RSD<5%)。肉松中钴含量最高,其平均值高达0.3285 mg/kg,其次是鱼肠和奶酪棒,蔬菜泥和水果泥中钴含量较低。食品安全国家标准只规定了婴幼儿食品中铅、汞、砷、锡的限量值,而对于钴元素未设定限量值,本研究可为今后制定营养素或污染物限量标准提供参考依据,以提高婴幼儿食品的质量和安全水平。 展开更多
关键词 金纳米星 婴幼儿食品 CO(ii) 比色检测 类芬顿反应
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瘦素/ERK信号在云锡矿粉诱导大鼠II型肺泡上皮细胞转化中的作用
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作者 胡雄 颜聪 +5 位作者 张宇 黎贵芸 周喆焱 阮永华 刘士岳 边莉 《中国肺癌杂志》 CAS CSCD 北大核心 2023年第10期732-740,共9页
背景与目的目前,云南个旧锡矿有大量矿工从事开采工作,这种职业环境与接触粉尘颗粒、重金属、多环芳烃和放射性氡有关,大大增加了患肺癌的风险。本研究旨在探讨在云锡矿粉诱导大鼠肺泡Ⅱ型上皮细胞(immortalized rat alveolar cells ty... 背景与目的目前,云南个旧锡矿有大量矿工从事开采工作,这种职业环境与接触粉尘颗粒、重金属、多环芳烃和放射性氡有关,大大增加了患肺癌的风险。本研究旨在探讨在云锡矿粉诱导大鼠肺泡Ⅱ型上皮细胞(immortalized rat alveolar cells type Ⅱ,RLE-6TN)恶性转化过程中,瘦素(leptin)及其介导的细胞外调节蛋白激酶(extracellular regulated protein kinase,ERK)信号通路所起的作用。方法采用200μg/mL的云锡矿粉隔代毒染RLE-6TN至第9代,建立毒染细胞模型,命名为R_(200)细胞,正常培养组命名为R细胞,通过Western blot法检测两种细胞leptin受体的表达情况。通过MTT法筛选出leptin及丝裂原活化蛋白激酶激酶(mitogen-activated protein kinase kinase,MEK)抑制剂(U0126)对R_(200)细胞的最佳作用浓度。自第20代起,将R组、R_(200)组细胞分别与leptin及MEK抑制剂U0126共培养,对各组细胞的形态改变进行观察,并利用苏木素-伊红(hematoxylin-eosin,HE)染色技术鉴别第40代细胞的形态学差异,通过刀豆凝集素A(concanavalin A,ConA)及锚着独立性生长实验法检测细胞恶性转化情况。通过Western blot法检测leptin作用后上皮细胞ERK信号通路的变化。结果R组和R_(200)组细胞均表达leptin受体(OB-R)。与R_(200)组比较,当leptin浓度达100 ng/mL时,其促增殖效应最为显著,30μmol/L U0126可抑制毒染细胞R_(200)增殖,与对照组相比具有统计学差异(P<0.05)。自第25代起,leptin诱导的R_(200)组(R_(200)L组)细胞形态发生变化,至第30代出现恶性转化,至第40代时恶性转化特征明显;而R_(200)组细胞及U0126诱导的R_(200)组(R_(200)LU组)细胞则在第40代时才出现恶性转化特征。R_(200)L组细胞凝集速度较R_(200)LU组快,其余各组细胞P30出现凝集,且随ConA浓度增加,细胞凝集速度加快。R_(200)L组细胞自P40可见克隆形成,克隆形成率为2.25‰±0.5‰,R_(200)LU组及R_(200)组未见克隆集落。R_(200)L组细胞pERK表达增强;加入U0126阻断后,R_(200)L组细胞pERK磷酸化水平降低。结论Leptin可以促进云锡矿粉毒染肺上皮细胞的恶性转化,ERK信号通路可能是其促进云锡矿粉引发的肺泡Ⅱ型上皮细胞转化的重要途径。 展开更多
关键词 瘦素 肺泡ii型上皮细胞 转化 ERK信号通路
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离子印迹磁性碳纳米球基电化学传感器用于铜(II)的选择性检测
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作者 李瑞珍 秦蕾 +5 位作者 符冬菊 王美玲 宋兴福 白永辉 刘伟峰 刘旭光 《新型炭材料(中英文)》 SCIE EI CAS CSCD 北大核心 2023年第6期1092-1103,共12页
本文报道一种基于Cu(II)离子印迹聚合物为识别元件的电化学传感器。通过耦合表面离子印迹和电化学沉积的制备方法,制备了由磁性碳纳米球组成的离子印迹聚合物电极。所组装的传感器表现出对Cu(II)检测的特异识别性和高灵敏特性。通过场... 本文报道一种基于Cu(II)离子印迹聚合物为识别元件的电化学传感器。通过耦合表面离子印迹和电化学沉积的制备方法,制备了由磁性碳纳米球组成的离子印迹聚合物电极。所组装的传感器表现出对Cu(II)检测的特异识别性和高灵敏特性。通过场发射扫描电子显微镜和透射电子显微镜对印迹聚合物的微观形貌进行表征,采用傅里叶变换红外光谱对其官能团和化学结构进行表征。传感器电化学性能表明,与非印迹电极和裸电极相比,印迹电极对Cu(II)具有更强的选择性和更高的灵敏度。传感器对浓度为10^(-6)至10^(-10) mol L^(-1)的Cu(II)表现出良好的线性相应电流,其检测限提升至5.138×10^(-16) mol L^(-1)(S/N=3)。此外,该传感器具有良好的抗干扰性、重现性和稳定性,为金属离子的检测提供了新的策略。 展开更多
关键词 离子印迹聚合物 电化学传感器 铜离子 磁性碳纳米球 选择性和灵敏性
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剖宫产术后腹壁切口愈合不良行II期缝合的相关因素分析 被引量:2
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作者 叶雨蓝 吴燕 马蔷 《浙江临床医学》 2023年第3期416-417,437,共3页
目的通过探讨剖宫产术后腹壁切口愈合不良行II期缝合的危险因素,降低II期缝合的发生概率。方法回顾性分析2021年1月至2021年10月收治的69例行剖宫产手术的患者资料。根据是否发生术后腹壁切口愈合不良并行II期缝合将患者分为观察组(n=10... 目的通过探讨剖宫产术后腹壁切口愈合不良行II期缝合的危险因素,降低II期缝合的发生概率。方法回顾性分析2021年1月至2021年10月收治的69例行剖宫产手术的患者资料。根据是否发生术后腹壁切口愈合不良并行II期缝合将患者分为观察组(n=10)和对照组(n=59)。结合年龄、体重指数(BMI)、是否合并GDM、是否术前胎膜早破、阴道检查次数、手术时间、术中出血量、术中羊水颜色是否正常、剖宫产术后第3天CRP值、切口分泌物培养结果等因素进行单因素分析及二分类Logistic回归分析。结果单因素分析结果示,阴道检查次数、新生儿窒息、BMI等观察指标与剖宫产术后的腹壁切口愈合不良行II期缝合有关(P<0.05)。二分类Logistic回归分析结果示,阴道检查次数(OR=1.255,95%CI:1.001~1.573,P=0.049),BMI(OR=1.271,95%CI:1.008~1.602,P=0.042)是剖宫产术后的腹壁切口愈合不良行II期缝合的独立危险因素。结论剖宫产术后的腹壁切口愈合不良行II期缝合的相关因素中围产期的阴道检查次数、BMI为其独立危险因素,在临床工作中,要加强孕期、围产期的管理,以减少剖宫产术后的腹壁切口愈合不良行II期缝合的发生率。 展开更多
关键词 剖宫产 腹壁切口 ii期缝合相关因素
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Environmentally Friendly Room Temperature Synthesis of 1-Tetralone over Layered Double Hydroxide-Hosted Sulphonato-Salen-Nickel(II) Complex
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作者 Samiran Bhattacharjee Mohammad A. Matin +1 位作者 Hasina Akhter Simol Anowar Hosen 《Green and Sustainable Chemistry》 CAS 2023年第1期9-22,共14页
1-Tetralone, a useful synthetic intermediate in the manufacture of pharmaceuticals, agrochemicals and dyes, can be prepared by liquid phase catalytic oxidation of tetralin. Selective oxidation of tetralin to 1-tetralo... 1-Tetralone, a useful synthetic intermediate in the manufacture of pharmaceuticals, agrochemicals and dyes, can be prepared by liquid phase catalytic oxidation of tetralin. Selective oxidation of tetralin to 1-tetralone is still a big challenge with low-temperature processes using environmentally friendly routes even after decades of research. Herein, we demonstrate room-temperature oxidation of tetralin to 1-tetralone over layered double hydroxide-hosted sulphonato-salen-nickel(II) complex, LDH-[Ni-salen]. The layered double hydroxide-hosted sulphonato-salen-nickel(II) compound was characterized by powder X-ray diffraction, Fourier transform infrared spectrometer (FTIR), UV-Visible diffuse reflectance spectra, scanning electron microscopy (SEM) and elemental analysis. The theoretical calculations of free sulphonato-salen-nickel(II) complex using Density Functional Theory/CAM-B3LYP at the 6-311++ G(d,p) level of theory were also used to determine the orientation of the Ni-salen compound within the layered structure. The immobilized compound, LDH-[Ni-salen] was found to be an effective reusable catalyst for the oxidation of tetralin to 1-tetralone using a combination of trimethylacetaldehyde and molecular oxygen (14.5 psi) and at 25&deg;C. At 45.5% conversion, tetralin was converted to 1-tetralone with 77.2% selectivity at room temperature and atmospheric pressure after 24 h. The catalyst recycles test and hot filtration experiment showed that oxidation proceeded through Ni(II) sites in LDH-[Ni-salen]. The catalysts were reused several times without losing their catalytic activity and selectivity. The present results may provide a convenient strategy for the preparation of 1-tetralone using layered double hydroxide-based heterogeneous catalyst at ambient temperature for industrial application in near future. 展开更多
关键词 Sulphonato-Salen-Nickel(ii) Layered Double Hydroxide Tetralin Oxidation Room Temperature 1-Tetralone
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Modeling of Fixed Bed Adsorption Column Parameters of Iron(II) Removal Using Ferrihydrite Coated Brick
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作者 Oscar Allahdin Eric Foto +3 位作者 Nicole Poumayé Olga Biteman Joseph Mabingui Michel Wartel 《American Journal of Analytical Chemistry》 CAS 2023年第4期184-201,共18页
Fixed-bed operating experimental column conditions were studied to evaluate the performance of brick from Bangui Region (in Central African Republic), coated with iron oxyhydroxide (ferrihydrite) for the removal of ir... Fixed-bed operating experimental column conditions were studied to evaluate the performance of brick from Bangui Region (in Central African Republic), coated with iron oxyhydroxide (ferrihydrite) for the removal of iron(II) from aqueous solution. The prediction of theoretical breakthrough profiles using Bohart and Adams sorption model was employed to achieve characteristic parameters such as depth of exchange zone, time required for exchange zone to move vertically, moving rate for the exchange zone and adsorption capacity useful for fixed-bed column reactor was investigated under varying operating conditions. The effects of bed depth and flow rate on iron(II) adsorption were studied. Our finding revealed that the Brick from Bangui Region (in Central African Republic), coated with ferrihydrite was a very efficient media for the removal of Fe(II) ions from water. The experimental data showed that the depth and the moving rate (10.3 ± 0.6 cm) and (0.208 ± 0.006 cm/min) respectively of the exchange zone (adsorption zone) were independent of variability of the height of the adsorbent bed column, however the variations of the flow rate affect the moving rate of the exchange zone. The bed depth service time (BDST) model was used and permitted us to predict the service times of columns operated at various flow rates and bed depths and these predicted values were compared with the experimental values. 展开更多
关键词 Iron Oxyhydroxide-Coated Brick Iron(ii)-Adsorption Column Study Break-through Curve BDST
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一个由原位反应制备的三维Pb(II)配合物及其在抗生素传感识别领域的应用
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作者 孙阳宇 张超 +3 位作者 汪兴淳 郝小瑄 罗万江 袁刚 《材料化学前沿》 2023年第4期77-86,共10页
在水热条件下使用半刚性的咪唑-4,5-二甲酸衍生物配体(H3L-1)和金属Pb(II)离子通过自组装反应成功获得一种无色的针状晶体。单晶X-射线衍射分析显示该配合物分子式为[Pb(L)]n (1),其中初始的H3L-1配体在高温条件下脱去了一个羧基形成了... 在水热条件下使用半刚性的咪唑-4,5-二甲酸衍生物配体(H3L-1)和金属Pb(II)离子通过自组装反应成功获得一种无色的针状晶体。单晶X-射线衍射分析显示该配合物分子式为[Pb(L)]n (1),其中初始的H3L-1配体在高温条件下脱去了一个羧基形成了L2‒形式,L2‒阴离子μ3-链接金属Pb(II)离子而形成了三维框架结构。拓扑分析显示配合物1的骨架是一个单节点的(3,3)-连接网络。配合物的晶相纯度,化学稳定性和热稳定性通过粉末X-射线衍射(PXRD)和热失重分析(TGA)等手段进行了表征。对配合物1的固态荧光性质进行了测定,结果显示配合物1是一种具有潜在应用价值的蓝光材料。此外,还对配合物1荧光传感性能进行了详细研究,测试多种常见的抗生素分子对配合物1荧光的影响,结果显示配合物1的荧光能够被以呋喃妥因(NFT)为代表的几种抗生素所猝灭,可作为检测这些抗生素分子的探针材料。 展开更多
关键词 Pb(ii)配合物 咪唑羧酸 原位反应 晶体结构 荧光传感 抗生素
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具免疫检查点抑制剂和Holling-II型功能反应的肿瘤模型稳定性分析
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作者 林晋章 朱惠延 欧映辰 《南华大学学报(自然科学版)》 2023年第6期68-74,共7页
肿瘤免疫检查点抑制剂治疗,是现代抗肿瘤的新型疗法。本文提出了一类具免疫检查点抑制剂anti-PD-1和Holling-II型功能反应的肿瘤免疫模型,研究了模型解的存在性与解的有界性,证明了模型的无肿瘤平衡点的局部渐近稳定的条件,最后通过数... 肿瘤免疫检查点抑制剂治疗,是现代抗肿瘤的新型疗法。本文提出了一类具免疫检查点抑制剂anti-PD-1和Holling-II型功能反应的肿瘤免疫模型,研究了模型解的存在性与解的有界性,证明了模型的无肿瘤平衡点的局部渐近稳定的条件,最后通过数值模拟验证理论分析的结果。 展开更多
关键词 肿瘤免疫模型 免疫检查点抑制剂anti-PD-1 Holling-ii型反应函数
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Synthesis, SAR, and in Silico ADME Screening Studies of Some 9-Amino-3-Phenylacridone Derivatives as Topoisomerase II Inhibitors
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作者 Abiodun S. Oyedele Toluwase H. Fatoki +2 位作者 Esha Dalvie Neil Osheroff Cosmas O. Okoro 《Open Journal of Medicinal Chemistry》 2023年第2期15-34,共20页
Cancer is a leading cause of death globally, claiming about 9.6 million lives and approximately 420 million new cases of cancer will be diagnosed in the world by the year 2025. The aim of this study was to synthesize ... Cancer is a leading cause of death globally, claiming about 9.6 million lives and approximately 420 million new cases of cancer will be diagnosed in the world by the year 2025. The aim of this study was to synthesize and computationally evaluate pharmacological potential of some derivatives of 9-amino-3-phenylacridone, as topoisomerase II (Topo II) inhibitors. In this study, 10 derivatives of 3-phenyl-9-aminoacridone were chemically synthesized and characterized, and the potential pharmacological indications of these compounds were computationally predicted by methods such as ADMET prediction, molecular target prediction and molecular docking. The results showed that two derivatives (58e and 58j) were non-permeant of blood-brain barrier, and this property was found similar to that of amsacrine and etoposide. The results of molecular docking of the ten derivatives of 3-phenyl-9-aminoacridone that were synthesized in this work showed that the synthetic compounds (58a-j) and the standard drugs have overall best binding affinities for human acetylcholine esterase than butyrylcholinesterase, and overall best binding affinities for human topo IIα than human topo IIβ. Overall, the results of this study suggest that the synthetic compounds 58a, 58c, 58f, 58g, and 58i could probably inhibit topo IIα by catalytic inhibition as seen with amsacrine, but only 58b and 58e possessed DNA non-intercalation properties as seen with etoposide, serving as topo II poison. In conclusion, this study showed that 3-phenyl-9-aminoacridone derivatives are potential inhibitor of topo IIα/β both by catalytic inhibition and poison as non-intercalator of DNA. 展开更多
关键词 CANCERS 9-Aminoacridone ANTICANCER Topoisomerase ii PHARMACOKINETICS Molecular Docking ETOPOSIDE
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Parameter Optimization of Intercalated Meltblown Nonwovens Based on NSGA-II
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作者 Peiyuan Jin Renjie Chu Quanxi Feng 《Journal of Computer and Communications》 2023年第3期146-158,共13页
The preparation process parameters of intercalated meltblown nonwoven materials are complicated, and the relationship between process parameters, structural variables, and product performance needs to be investigated ... The preparation process parameters of intercalated meltblown nonwoven materials are complicated, and the relationship between process parameters, structural variables, and product performance needs to be investigated to establish a good mechanism for product performance regulation. In this study, we first used Wilcoxon test and Pearson correlation analysis to investigate the effect of intercalation rate on structural variables and product performance. Then, regression models were constructed to predict the values of each structural variable under different combinations of process parameters. Finally, we constructed a multi-objective constrained optimization problem based on the stepwise regression model and the product variable conditions. The problem was solved using the NSGA-II algorithm. The optimal was achieved when the acceptance distance was 2.892 cm and the hot air speed was 2000 r/min. 展开更多
关键词 Regression Model NSGA-ii Algorithm Meltblown Nonwovens Parameter Optimization
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Dynamic Analysis of a Predator-Prey Model with Holling-II Functional Response
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作者 Jiemin Mo Wanying Li +2 位作者 Donghuan He Songbo Wang Xiaoliang Zhou 《Journal of Applied Mathematics and Physics》 2023年第10期2871-2878,共8页
A predator-prey model with linear capture term Holling-II functional response was studied by using differential equation theory. The existence and the stabilities of non-negative equilibrium points of the model were d... A predator-prey model with linear capture term Holling-II functional response was studied by using differential equation theory. The existence and the stabilities of non-negative equilibrium points of the model were discussed. The results show that under certain limited conditions, these two groups can maintain a balanced position, which provides a theoretical reference for relevant departments to make decisions on ecological protection. 展开更多
关键词 Predator-Prey Model Holling-ii Functional Response Equilibrium Point STABILITY
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基于NSGA-II结合BP网络算法的乙醇制备C4烯烃优化模型
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作者 杨杰 《山东化工》 CAS 2023年第17期57-62,共6页
乙醇偶合制备C4烯烃工艺广泛应用于化工生产,探寻实现乙醇转化率与烯烃收率最大化的催化剂组合与温度条件具有重要意义。根据反应过程性能数据,分别运用多元回归与BP网络建立反应条件与烯烃收率的回归预测模型,结果表明BP网络模型对烯... 乙醇偶合制备C4烯烃工艺广泛应用于化工生产,探寻实现乙醇转化率与烯烃收率最大化的催化剂组合与温度条件具有重要意义。根据反应过程性能数据,分别运用多元回归与BP网络建立反应条件与烯烃收率的回归预测模型,结果表明BP网络模型对烯烃收率的预测值有较高的精度。建立多目标优化模型,基于BP网络良好的预测能力,采用NSGA-II算法进一步优化可得满足目标的催化剂与温度方案,此时乙醇转化率与烯烃收率分别为64.67%,35.921%。随后进一步分析比较NSGA-II算法和经典遗传算法分别优化BP网络模型获得的烯烃收率预测误差,验证了所用算法的精确性与有效性。 展开更多
关键词 烯烃收率预测 多目标优化 BP神经网络 NSGA-ii算法
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The Role for AVE0991 (MAS-Receptor Angiotensin II (1-7) Agonist) in Reducing Cisplatin-Induced Acute Kidney Injury on C57BL/6 Mice
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作者 Chris Mathew 《Journal of Biosciences and Medicines》 CAS 2023年第1期195-214,共20页
Acute Kidney Injury (AKI) is a condition that causes nephrotoxicity in kidney tissues due to cisplatin-induced cancer treatments. Hence, it is proposed in this review that AVE0991 (a MAS-receptor Angiotensin II (1-7) ... Acute Kidney Injury (AKI) is a condition that causes nephrotoxicity in kidney tissues due to cisplatin-induced cancer treatments. Hence, it is proposed in this review that AVE0991 (a MAS-receptor Angiotensin II (1-7) agonist) may reduce cisplatin-induced acute kidney injury by promoting nitric oxide production. 展开更多
关键词 CISPLATIN Acute Kidney Injury AKI Cisplatin-Induced Acute Kidney Injury NEPHROTOXICITY Renal Renin Angiotensin System RAS AVE0991 MAS-Receptor Angiotensin ii (1-7) Agonist
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