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Prediction of alloy composition and microhardness by random forest in maraging stainless steels based on a cluster formula

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Journal of Iron and Steel Research International 2018年第7期25卷 717-723页

作者： Zhen Li Dong-hui Wen Yue ma QingWang Guo-qing Chen Rui-qian Zhang Rui Tang Huan He School of Mechanical Engineering Dalian University of Technology Dalian 116024 Liaoning China Key Laboratory of materials Modification by Laser Ion and Electron Beams (Ministry of Education) School of Materials Science and Engineering Dalian University of Technology Dalian 116024 Liaoning China Science and Technology on Reactor Fuel and materials Laboratory Nuclear Power Institute of China Chengdu 610213 Sichuan China Ministry-Province Jointly-Constructed Cultivation Base for State Key Laboratory of Processing for Non-Ferrous Metal and Featured materials Guangxi University Nanning 530004 Guangxi China

Fe-Ni-Cr-based super-high-strength maraging stainless steels were generally realized by multiple-element alloying under a given heat treatment processing. A series of alloy compositions were designed with a uniform cluster formula of [Ni16Fe192]（Cr32（Ni16-x-y-z-m-n MoxTiyNbzAlmVn））（at.%） that was developed out of a unique alloy design tool, a cluster- plus-glue-atom model. Alloy rods with a diameter of 6 mm were prepared by copper-mold suction-cast processing under the argon atmosphere. These alloy samples were solid-solutioned at 1273 K for 1 h, followed by water-quenching, and then aged at 783 K for 3 h. The effect of the valence electron concentration, characterized with the number of valence electrons per unit cluster （ve/uc） formula of 16 atoms, on microhardness of these designed maraging stainless steels at both solid- solutioned and aged states was investigated. The relationship between alloy compositions and microhardness in maraging stainless steels was firstly established by the random forest （RF, a kind of machine learning methods） based on the experimental results. It was found that not only the microhardness of any given composition alloy within the frame of cluster formula, but also the alloy composition with a maximum microhardness for any given ve/uc, could be predicted in good agreement with the guidance of the relationship by RF. The contributions of minor-alloying elements to the microhardness of the aged alloys were also discussed.

关键词： maraging stainless steel Composition design Microhardness Valence electron concentration Random forest

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From fundamental quantum optics to quantum information technology:the personal journey of Sir Peter Knight

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Advanced Photonics 2021年第6期3卷 3-7页

作者： Xiaosong ma Peter Knight Nanjing University School of PhysicsNanjingChina the Physics Department at Imperial College the UK National Quantum Technology Programme Strategic Advisory Board the National Physical Laboratory Quantum Metrology Institute

Xiaosong ma:What inspired you to choose quantum optics as your major when you were a student,and can you share your experience or research journey in this field?Peter Knight:Quantum optics,as a discipline,was more or less formed during the time I’ve been active in the area.I started thinking about things that we would now call quantum optics in the middle of the 1960s when I was a student.

关键词： optics quantum Quantum

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Effects of stocking density on the growth and immunity of Atlantic salmon salmo salar reared in recirculating aquaculture system(RAS)

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Journal of Oceanology and Limnology 2019年第1期37卷 350-360页

作者： WANG Yanfeng CHI Liang LIU Qinghua XIAO Yongshuang ma Daoyuan XIAO Zhizhong XU Shihong LI Jun CAS Key Laboratory of Experimental marine Biology Institute of Oceanology Chinese Academy of Sciences Laboratory for marine Biology and Biotechnology Qingdao National Laboratory for Marine Science and Technology Center for Ocean Mega-Science Chinese Academy of Sciences College of veterinary Medicine Qingdao Agricultural University

Atlantic salmon reared in recirculating aquaculture system(RAS) may lead to inappropriately high stocking density, because ?sh live in a limited space. Finding the suitable stocking density of Atlantic salmon reared in RAS is very important for RAS industry. In this paper, the in?uence of stocking density on growth and some stress related physiological factors were investigated to evaluate the ef fects of stocking density. The ?sh were reared for 220 days at ?ve densities(A: 24 kg/m^3; B: 21 kg/m^3; C: 15 kg/m^3; D: 9 kg/m^3 and E: 6 kg/m^3). The results show that 30 kg/m^3 might be the maximum density which RAS can af ford in China. The stocking densities under 30 kg/m^3 have no ef fect on mortality of Atlantic salmon reared in RAS. However, the speci?c growth rate(SGR), ?nal weight and weight gain in the high density group were signi?cantly lower than the lower density groups and middle density groups. Moreover, feed conversion rate(FCR) had a negative correlation with density. Plasma hormone T_3 and GH showed signi?cant decrease with the increase of the stocking density of the experiment. Furthermore, thyroid hormone(T 3), GH(growth hormone) activities were decreased with stocking density increase. However, plasma cortisol, GOT(glutamic oxalacetic transaminase) and GPT(glutamic pyruvic transaminase) activities were increase with stocking density increase. And the stocking density has no ef fects on plasma lysozyme of Atlantic salmon reared in RAS. These investigations would also help devise effcient ways to rear adult Atlantic salmon in China and may, in a way, help spread salmon mariculture in China.

关键词： stocking density growth physiological parameters Atlantic salmon RAS

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Conspicuous cruciform silk decorations deflect avian predator attacks

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Integrative Zoology 2022年第5期17卷 689-703页

作者： Bingjun WANG Long YU Nina ma Zengtao ZHANG Deyong GONG Rui LIU Daiqin LI Shichang ZHANG Centre for Behavioural Ecology and Evolution&State Key Laboratory of Biocatalysis and Enzyme Engineering School of Life SciencesHubei UniversityWuhanHubeiChina Department of Biological Sciences National University of SingaporeSingapore

Although camouflage as an effective antipredator defense strategy is widespread across animals,highly conspicuous color patterning is not uncommon *** orb-web spiders adorn their webs with extra bright white *** conspicuous decorations are hypothesized to deter predators by warning the presence of sticky webs,camouflaging spiders,acting as a decoy,or intimidating predators by their apparent *** decorations may also deflect predator attacks from ***,empirical evidence for this deflection function remains ***,we tested this hypothesis using the X-shaped silk cruciform decorations built by females of Argiope *** employed visual modeling to quantify the conspicuousness of spiders and decorations from a perspective of avian ***,we determined actual predation risk on spiders using naïve chicks as *** bodies and decorations were conspicuous against natural backgrounds to the avian visual *** attacked the spider main bodies significantly less frequently on the decorated webs than on the undecorated webs,thus reducing predation *** both spiders and decorations were present,chicks also attacked the spider main bodies and their legs or decorations,and not randomly:they attacked the legs or decorations sooner and more frequently than they attacked the main bodies,independent of the ratio of the surface area between the decoration and spider *** the increase in detectability,incorporating a conspicuous cruciform decoration to the web effectively defends the spider by diverting the attack toward the decoration or leg,but not by camouflaging or intimidating,thus,supporting the deflection hypothesis.

关键词： Argiope minuta cruciform decoration predator deflection visual defense visual modeling

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Effect of CXCR4 pretreated with ultrasound-exposed microbubbles on accelerating homing of bone marrow mesenchymal stem cells to ischemic myocardium in AMI rats

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Asian Pacific Journal of Tropical Medicine 2015年第9期8卷 751-756页

作者： Jun-Yi Gu Hui-Fen Shi Xiu-Li Gao Qing-Qing ma Bo Zhang Department of Ultrasound in Medicine East Hospital Tongji University School of Medicine

Objective: To investigate the role and potential mechanism of CXCR4 in promoting targeted homing of bone marrow mesenchymal stem cells(BMSCs) with ultrasound-exposed microbubbles(UM) pretreatment. Methods: Third generation BMSCs were divided into four groups control group, ultrasound(US) group, UM group and ultrasound-exposed microbubbles plus catalase group. RT-PCR and western blot were performed to determine the levels of CXCR4 m RNA transcription and protein expression, respectively. Third generation BMSCs were labeled with Fluo-α/AM and divided into three groups: control group, US group and UM group, and flurorescence intensities in the cells were observed immediately, 5 min and 15 min after intervention underflurorescence microscope. The calcium iron levels in the cells were analyzed. BMSCs were divided into i ve group: group A without calcium in the medium, group B, group C, group D and group E containing calcium chloride with concentration of l mol, 2 mol, 4mol, anti-calciurn-sensing receptor antibody, respectively. RT-PCR and western blot were performed to determine the levels of CXCR4 m RNA transcription and proteins expression of the third generation BMSCs of each group, respectively. Results: The levels of CXCR4 m RNA transcription and protein expression between US group and control group had no statistically signii cant dif erence(P>0.05) shown by RT-PCR and western blot; the transcription level in the UM group was signii cantly higher than that in US group and control group(Pvel was much lower than that in UM group. Fluorescence intensify in the cells of US group had no signii cant dif erence compared with that in the cells of the control group(P>0.05), which in the cells of UM group was signii cantly higher than that in the cells of both US group and control group(P<0.05). Compared to group A, expressions of CXCR4 of group B to D were signii cantly increased in

关键词： Ultrasound-exposed microbubbles Bone marrow mesenchymal stem cells CXCR4 Calciumion

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Kunxian Capsule Extract Inhibits Angiogenesis in Zebrafish Embryos via PI3K/AKT-maPK-veGF Pathway

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Chinese Journal of Integrative Medicine 2023年第2期29卷 137-145页

作者： ma Rui-jiao maharajan Kannan XIA Qing ZHANG Shan-shan TU Peng-fei LIU Ke-chun ZHANG Yun Biology Institute Qilu University of Technology(Shandong Academy of Sciences)Jinan 250103China Engineering Research Center of Zebrafish Models for Human Diseases and Drug Screening of Shandong Province Jinan 250103China State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical SciencesPeking UniversityBeijing 100191China

Objective: To investigate the anti-angiogenic activity of Kunxian Capsule(KX) extract and explore the underlying molecular mechanism using zebrafish. Methods: The KX extract was prepared with 5.0 g in 100 mL of 40% methanol followed by ultrasonication and freeze drying. Freeze dried KX extract of 10.00 mg was used as test stock solution. Triptolide and icariin, the key bioactive compounds of KX were analyzed using ultra-high performance liquid chromatography. The transgenic zebrafish Tg(flk1:GFP) embryos were dechorionated at 20-h post fertilization(hpf) and treated with PTK 787, and 3.5, 7, 14 and 21 μg/m L of KX extract, *** 24-h post exposure(hpe), mortality and malformation(%), intersegmental vessels(ISV) formation, and m RNA expression level of angiogenic pathway genes including phosphoinositide 3-kinase(PI3K), protein kinase B(AKT),extracellular signal-regulated kinases(ERKs), mitogen-activated protein kinase(maPK), vascular endothelial growth factor(veGF) and fibroblast growth factor(FGF-2) were determined. Further, the embryos at 72 hpf were treated with KX extract to observe the development of sub-intestinal vein(SIV) after 24 hpe. Results: The chromatographic analysis of test stock solution of KX extract showed that triptolide and icariin was found as 0.089 mg/g and 48.74 mg/g, respectively, which met the requirements of the national drug standards. In zebrafish larvae experiment, KX extract significantly inhibited the ISV(Pmation(Pvels of ERKs and maPK. Moreover, the downstream signaling cascade affected the expression of veGF and its receptors(veGFR and veGFR-2). FGF-2, a strong angiogenic factor, was also downregulated by KX treatment in zebrafish larvae. Conclusion: KX extract exhibited anti-angiogenic effects in zebrafish embryos by regulating PI3K/AKT-maPK-ve

关键词： angiogenesis rheumatoid arthritis synovial inflammation osteoporosis Chinese medicine

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Exploring the Feasibility of machine Learning to Predict Risk Stratification Within 3 Months in Chest Pain Patients with Suspected NSTE-ACS

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Biomedical and Environmental Sciences 2023年第7期36卷 625-634页

作者： ZHENG Zhi Chang YUAN Wei WANG Nian JIANG Bo ma Chun Peng AI Hui WANG Xiao NIE Shao Ping Cardiovascular Medicine Department Beijing Bo’ai HospitalChina Rehabilitation Research CenterCapital Medical UniversityBeijing 100068China Center for Coronary Artery Disease Beijing Anzhen HospitalCapital Medical UniversityBeijing 100029China Respiratory Medicine Department Beijing Friendship Hospital Affiliated of Capital Medical UniversityBeijing 100050China School of Computer Science and Engineering Beihang UniversityBeijing 100191China Department of Cardiology the First Hospital of QinhuangdaoHebei Medical UniversityQinhuangdao 066001HebeiChina

Objective We aimed to assess the feasibility and superiority of machine learning(ML)methods to predict the risk of major Adverse Cardiovascular Events(maCEs)in chest pain patients with *** Enrolled chest pain patients were from two centers,Beijing Anzhen Emergency Chest Pain Center Beijing Bo’ai Hospital,China Rehabilitation Research *** classifiers were used to develop ML ***,Precision,Recall,F-Measure and AUC were used to assess the model performance and prediction effect compared with HEART risk scoring ***,ML model constructed by Naïve Bayes was employed to predict the occurrence of *** According to learning metrics,ML models constructed by different classifiers were superior over HEART(History,ECG,Age,Risk factors,&Troponin)scoring system when predicting acute myocardial infarction(AMI)and all-cause ***,according to ROC curves and AUC,ML model constructed by different classifiers performed better than HEART scoring system only in prediction for *** the five ML algorithms,Linear support vector machine(SVC),Naïve Bayes and Logistic regression classifiers stood out with all Accuracy,Precision,Recall and F-Measure from 0.8 to 1.0 for predicting any event,AMI,revascularization and all-cause death(***≤0.78),with AUC from 0.88 to 0.98 for predicting any event,AMI and revascularization(***≤0.85).ML model developed by Naïve Bayes predicted that suspected acute coronary syndrome(ACS),abnormal electrocardiogram(ECG),elevated hs-cTn I,sex and smoking were risk factors of *** Compared with HEART risk scoring system,the superiority of ML method was demonstrated when employing Linear SVC classifier,Naïve Bayes and *** method could be a promising method to predict maCEs in chest pain patients with NSTE-ACS.

关键词： machine learning maCEs Chest pain Suspected NSTE-ACS

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芪参益气滴丸对气虚血瘀型冠心病患者心功能、运动耐量及生活质量的影响

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中医学报 2024年第7期39卷 1551-1560页

作者：高建凯冯娟马会华闫奎坡吴雷唐聚花河南中医药大学第五临床医学院/郑州人民医院河南郑州450003 郑州澍青医学高等专科学校河南郑州450064 河南中医药大学第一附属医院心脏中心/国家区域(中医)心血管诊疗中心河南郑州450000

目的:观察芪参益气滴丸对不宜进行血运重建的气虚血瘀型冠状动脉粥样硬化性心脏病(简称“冠心病”)患者的心功能、运动耐量和生活质量的影响。方法:将符合诊断标准和病例纳入、排除标准的114例冠心病患者,随机分为试验组62例和对照组52... 详细信息

目的:观察芪参益气滴丸对不宜进行血运重建的气虚血瘀型冠状动脉粥样硬化性心脏病(简称“冠心病”)患者的心功能、运动耐量和生活质量的影响。方法:将符合诊断标准和病例纳入、排除标准的114例冠心病患者,随机分为试验组62例和对照组52例。对照组给予冠心病二级预防的规范药物治疗,试验组在对照组治疗方案的基础上加用芪参益气滴丸,连续治疗3个月。结果:两组患者的心肺运动试验(cardio pulmonary exercise testing,CPET)相关指标、左室舒张末期内径(left ventricular end diastolic dimension,LveDD)、左室射血分数(left ventricular ejection fraction,LveF)、红细胞分布宽度变异系数(red blood cell distribution width coefficient of variation,RDW-CV)、低密度脂蛋白胆固醇(low density lipoprotein cholesterol,LDL-C)较治疗前均得到显著改善(Pmax)、无氧阈时摄氧量(AT-VO_(2)/kg)、无氧阈时代谢当量(AT-METs)、最大代谢当量(METs max)、二氧化碳通气当量斜率(ve/VCO_(2)-slope)、最大摄氧量占预计值的百分比(VO_(2) max%pred)、LveF改善程度显著优于对照组(Pvey,SF-36)各项评分均较治疗前显著提高(P<0.05),而试验组在生理机能、生理职能、一般健康状况、精力、社会功能以及健康变化方面显著优于对照组(P<0.05);两组西雅图心绞痛量表(Seattle angina questionnaire,SAQ)各项评分均较治疗前显著改善(P<0.05),试验组在躯体活动受限程度、治疗满意程度和疾病认知程度方面的改善程度显著优于对照组(P<0.05)。结论:芪参益气滴丸联合常规西药治疗,可改善不宜进行血运重建的气虚血瘀型冠心病患者的CPET相关指标,提高患者的心功能、运动耐量和生活质量水平。

关键词：冠状动脉粥样硬化性心脏病气虚血瘀证芪参益气滴丸心功能运动耐量生活质量

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四川省5所学校流感暴发疫情中2022—2023年季节性流感疫苗保护效果回顾性队列研究

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中国公共卫生 2024年第2期40卷 129-134页

作者：李秋玲张丽杰马会来张金瑞李昀杨建强李媛媛周丽君刘伦光中国疾病预防控制中心中国现场流行病学培训项目北京100050 北京市大兴区疾病预防控制中心北京大兴102600 四川省旺苍县疾病预防控制中心广元628200 四川省资中县疾病预防控制中心内江641200 四川省疾病预防控制中心成都610041

目的分析2022—2023年流感季接种流感疫苗在学校流感暴发疫情中的保护效果,为流感疫苗接种策略提供科学依据。方法以2023年2—4月四川省5所发生流感暴发疫情的小学、初中,幼小综合学校班级确诊病例数≥2例的班级学生为调查对象,采用回... 详细信息

目的分析2022—2023年流感季接种流感疫苗在学校流感暴发疫情中的保护效果,为流感疫苗接种策略提供科学依据。方法以2023年2—4月四川省5所发生流感暴发疫情的小学、初中,幼小综合学校班级确诊病例数≥2例的班级学生为调查对象,采用回顾性队列研究方法评估流感疫情期间疫苗的保护效果。采用多因素logistic回归计算流感疫苗对临床诊断病例和确诊病例的保护效果[ve_(adj)=(1-RR_(adj))×100%],调整的变量为就读学段、学校和年龄组。结果共纳入4087名研究对象,流感疫苗接种率为19.0%。发病1352例,发病率为33.1%,其中,疑似病例401例、临床诊断病例659例、确诊病例292例。接种流感疫苗对临床诊断病例和确诊病例的ve_(adj)(95%CI)为26.0%(0.6%~44.9%)。分层分析显示,接种时间与发病时间间隔在[14,120]d和(120,180]d的ve_(adj)(95%CI)分别为78.3%(59.8%~88.3%)和58.6%(35.6%~73.4%),时间间隔>180 d无保护效果;接种四价流感疫苗接种时间与发病时间间隔在[14,120]d和(120,180]d的ve_(adj)(95%CI)分别为81.4%(63.8%~90.4%)和62.3%(40.7%~76.0%);接种时间与发病时间间隔为[14,120]d和(120,180]d对A(H1N1)亚型引起的流感暴发疫情的ve_(adj)(95%CI)分别为73.4%(12.1%~92.0%)和87.1%(74.7%~93.4%)。结论接种流感疫苗对学校暴发疫情中预防流感有一定的保护效果,当季接种时间与发病时间间隔在6个月内保护效果最佳,时间间隔越短保护效果越好,应采取综合政策措施积极推动流感疫苗预防接种工作。

关键词：流行性感冒暴发疫情流感疫苗保护效果回顾性队列研究

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A Helping Hand

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Beijing Review 2016年第46期59卷 32-33页

作者： ma Li

Local social workers help those with disabilities to start anew By ma Li Every morning at 9 o＇clock,Song Enlan,who works at the Huixinyuan Community in Beijing＇s Chaoyang District,arrives at Warm Homeland,a center for the recovery of people with disabilities in Xiaoguan Subdistrict of Chaoyang Her daily routine starts by greeting her friends who come for recovery training.＂I＇ve been here for almost two years.

关键词：英语阅读理解社会工作者

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