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Journal of magnesium and Alloys 2023年第2期11卷 753-761页

作者： Chaosheng ma Wenbo YU Tongtong Zhang Zihua Zhang Yihu ma Shoumei Xiong Center of materials Science and Engineering School of Mechanical and Electronic Control EngineeringBeijing Jiaotong UniversityBeijing 100044China Research Center of Rail Vehicles Safety monitoring and Health management Beijing Jiaotong UniversityBeijing 100044China School of materials Science and Engineering Tsinghua UniversityBeijing 100084China

3D reconstruction and 2D observation were conducted to characterize the microstructure of the castings produced through high pressure die casting with different *** results indicate that shrinkage pores generally co-existed with externally solidiﬁed crystals(ESCs).In specimen produced without fast slow shot speed,big net-shrinkage pores accompanied with ESCs were found in the center of the *** the casting pressurization was introduced,the shrinkage pores gathered to the specimen center and became much less due to the optimization of melt *** more porosity was found near the gate rather than in the middle of the rod bar,especially gas ***ﬁlling process simulation reveals that the middle position of the bars wasﬁrstlyﬁlled and followed by the near gate position accompanied with one intense turbulentﬂow.

关键词： HPDC parameters Externally solidiﬁed crystals(ESCs) Porosity 3D reconstruction.

Insights into the origin of precipitation moisture for tropical cyclones during rapid intensification process

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Tropical Cyclone Research and Review 2024年第2期13卷 72-87页

作者： Albenis Perez-Alarcon Jose C.Fernandez-Alvarez Ricardo m.Trigo Raquel Nieto Luis Gimeno Centro de Investigacion mari~na Universidade de VigoEnvironmental Physics Laboratory(EPhysLab)Campus As Lagoas s/nOurenseSpain Departamento de meteorología Instituto Superior de Tecnologías y Ciencias AplicadasUniversidad de La HabanaLa HabanaCuba Instituto Dom Luiz(IDL) Facultade de Ci^enciasUniversidade de LisboaLisboaPortugal Departamento de meteorologia Universidade Federal do Rio de JaneiroRio de JaneiroBrazil

In this study,we identiﬁed the moisture sources for the precipitation associated with tropical cyclones(TCs)during the rapid intensiﬁcation(RI)process from 1980 to 2018 by applying a Lagrangian moisture source diagnostic *** detected sixteen regions on a global scale for RI events distributed as follows:four in the North Atlantic(NATL),two in the Central and East Paciﬁc Ocean(NEPAC),the North Indian Ocean(NIO)and South Indian Ocean(SIO),and three in the South Paciﬁc Ocean(SPO)and the Western North Paciﬁc Ocean(WNP).The moisture uptake(mU)mostly was from the regions where TCs underwent *** Western NATL,tropical NATL,Caribbean Sea,the Gulf of mexico and the Central America and mexico landmass supported~85.4%of the precipitating moisture in the NATL,while the latter source and the eastern North Paciﬁc Ocean provided the higher amount of moisture in NEPAC(~84.3%).The Arabian Sea,the Bay of Bengal and the Indian Peninsula were the major moisture sources in NIO,contributing approximately 81.3%.The eastern and western parts of the Indian Ocean supplied most of the atmospheric humidity in SIO(~83.8%).The combined contributions(~87.9%)from the western and central SPO and the Coral Sea were notably higher in ***,TCs in the WNP basin mostly received moisture from the western North Paciﬁc Ocean,the Philippine Sea and the China Sea,accounting for 80.1%.The remaining moisture support in each basin came from the summed contributions of the remote ***,RI TCs gained more moisture up to 2500 km from the cyclone centre than those slow intensiﬁcation(SI)and the total mU was approximately three times higher during RI than ***,the patterns of the mU differences respond to the typical pathways of moisture transport in each basin.

关键词： Tropical cyclones Rapid intensiﬁcation moisture sources Precipitation Lagrangian moisture tracking

Autophagy, apoptosis and organelle features during cell exposure to cadmiumč

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BIOCelL 2013年第2期37卷 45-54页

作者： CRISTIANE DOS SANTOS VERGILIO edÉSIO JOSÉTENÓRIO DE melO Universidade Estadual do Norte Fluminense Centro de Biociências e BiotecnologiaLaboratório de Biologia Celular e TecidualCampos dos GoytacazesRJBrasil28013-602.

Cadmium(Cd)induces several effects in different tissues,but our knowledge of the toxic effects on organelles is insuffi *** observe the progression of Cd effects on organelle structure and function,HuH-7 cells(human hepatic carcinoma cell line)were exposed to CdCl2 in increasing concentrations(1μm–20μm)and exposure times(2 h–24 h).During Cd treatment,the cells exhibited a progressive decrease in viability that was both time-and *** treated cells displayed progressive morphological changes that included cytoplasm retraction and nuclear condensation preceding a total loss of cell *** with 10μm for 12 h led to irreversible *** these drastic and irreparable damages,treated cells(5μm for 12 h)presented a progressive loss of mitochondrial function and cytoplasm acidifi cation as well as dysfunction and disorganization of microfi laments and endoplasmic *** damages led to the induction of apoptotic events and an increase in autophagic bodies in the *** results revealed that Cd affects multiple intra-cellular targets that induce alterations in the mitochondria,cytoskeleton,endoplasmic reticulum and acidic compartments,ultimately culminating in cell death via apoptotic and autophagic pathways.

关键词： Cd cell death hepatocyte HuH-7 cells mitochondria

急性ST段抬高型心肌梗死合并心脏破裂的列线图模型建立

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中国动脉硬化杂志 2024年第5期32卷 415-423页

作者：吴鹏严宁马娟王墨函贾绍斌马学平宁夏医科大学研究生院宁夏银川市750004 宁夏医科大学总医院心血管内科宁夏银川市750004

[目的]分析急性ST段抬高型心肌梗死(STEmI)患者发生心脏破裂(CR)的风险因素,并依此构建急性STEmI患者合并CR的列线图模型。[方法]通过宁夏医科大学总医院大数据研究平台、医院信息系统检索连续纳入2015年1月—2019年12月急性STEmI患者5... 详细信息

[目的]分析急性ST段抬高型心肌梗死(STEmI)患者发生心脏破裂(CR)的风险因素,并依此构建急性STEmI患者合并CR的列线图模型。[方法]通过宁夏医科大学总医院大数据研究平台、医院信息系统检索连续纳入2015年1月—2019年12月急性STEmI患者5412例,其中合并CR的91例患者为CR组,5321例未合并CR患者为非CR组。运用LASSO回归、单因素及多因素Logistic回归分析急性STEmI患者合并CR的风险因素,并建立CR的列线图预测模型。分别运用受试者工作特征曲线、Hosmer-Lemeshow检验、临床决策曲线分析法(DCA)对建立的列线图模型进行验证和评估。[结果]LASSO回归结果显示年龄、女性、高血压病史、首次医疗接触时间、休克指数、Killip分级、白细胞计数、D二聚体、乳酸、前壁心肌梗死、24 h内服用β受体阻滞剂、24 h内服用血管紧张素转化酶抑制剂/血管紧张素受体拮抗剂(ACEI/ARB)药物、急诊PCI共13个变量为CR的风险因素(PmI患者合并CR的风险因素。依据上述6个风险变量建立急性STEmI合并CR列线图模型。该列线图模型内部验证前后ROC曲线下面积分别为0.946(95%CI:0.927~0.961)、0.947(95%CI:0.927~0.959),灵敏度分别为0.957、0.904,特异度分别为0.858、0.876,说明该模型具有较好的区分度。运用Hosmer-Lemeshow检验证明该模型的预测价值和实际观测值之间的偏差没有统计学意义(χ^(2)=12.70,P=0.122),说明列线图模型具有较好的校准度。DCA曲线提示模型的预测概率阈值在0.00~0.40之间,临床净获益最高,说明具有较好的临床效能。[结论]本研究建立的列线图模型有较好的区分度、校准度和临床效能,能有效预测急性STEmI合并CR的发生概率,为临床诊疗工作提供一定帮助,以期降低CR发生率。

关键词：急性ST段抬高型心肌梗死心脏破裂风险因素列线图

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混维凹凸棒石对矿区土壤重金属的钝化修复

环境科学与技术 2024年第4期47卷 152-158页

作者：马贵任珺陶玲吕麦蓉牛乐乐兰州交通大学环境与市政工程学院甘肃兰州730070 甘肃瀚兴环保科技有限公司甘肃兰州730070 宁夏师范学院化学化工学院宁夏固原756000

该文在引入外源Si^(2+)、Ca^(2+)和mg^(2+)条件下,将混维凹凸棒石水热改性为新型凹凸棒石钝化材料(PSmC),用扫描电镜、X射线衍射和傅立叶红外光谱对其进行了表征,通过钝化试验探究了其对矿区土壤中重金属的钝化效果。结果表明,水热处理... 详细信息

该文在引入外源Si^(2+)、Ca^(2+)和mg^(2+)条件下,将混维凹凸棒石水热改性为新型凹凸棒石钝化材料(PSmC),用扫描电镜、X射线衍射和傅立叶红外光谱对其进行了表征,通过钝化试验探究了其对矿区土壤中重金属的钝化效果。结果表明,水热处理能使凹凸棒石及其伴生矿物转变为具有晶体结构缺陷的无定形或低结晶硅酸盐。土壤中Cd、Pb、Cu和Zn的二乙烯三胺五乙酸提取态含量在所有PSmC添加处理下均显著降低,且均在5%(w/w)的添加处理下达到最小;添加PSmC促使酸溶态的Cd、Pb、Cu和Zn向更加稳定的残渣态转化;5%的PSmC添加处理下,Cd、Pb、Cu和Zn的钝化效率分别为91.15%、84.70%、90.51%和90.09%。根据土壤管控标准风险等级,重金属的总体污染潜在风险指数随着PSmC添加量的增加而减小,Pb、Cu和Zn的环境风险指数均小于1%,Cd的的环境风险指数均小于3%(低风险)。水热改性能提高混维凹凸棒石对矿区土壤中重金属的钝化能力,进而为甘肃混维ATP黏土高值化利用提供新思路、新方法。

关键词：水热改性凹凸棒石重金属钝化

Challenges and opportunities in improving left ventricular remodelling and clinical outcome following surgical and trans-catheter aortic valve replacement

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Frontiers of medicine 2021年第3期15卷 416-437页

作者： Xu Yu Jin mario Petrou Jiang Ting Hu ed D Nicol John R Pepper Surgical Echo-Cardiology Services Oxford Heart CentreJohn Radcliffe HospitalOxford University Hospitals NHS Foundation TrustOxford OX39DUUK Cardiac Surgical Physiology and Genomics Group Nuffield Division of Clinical Laboratory SciencesRadcliffe Department of MedicineUniversity of OxfordOxford OX39DUUK Department of Cardiac Surgery Royal Brompton HospitalLondon SW36NPUK National Heart and Lung Institute Imperial College LondonLondon SW36LYUK NIHR Imperial Biomedical Research Centre London W21NYUK Department of Cardiology Royal Brompton HospitalLondon SW36NPUK

Over the last half century,surgical aortic valve replacement(SAVR)has evolved to offer a durable and efficient valve haemodynamically,with low procedural complications that allows favourable remodelling of left ventricular(LV)structure and *** latter has become more challenging among elderly patients,particularly following trans-catheter aortic valve implantation(TAVI).Precise understanding of myocardial adaptation to pressure and volume overloading and its responses to valve surgery requires comprehensive assessments from aortic valve energy loss,valvular-vascular impedance to myocardial activation,force-velocity relationship,and myocardial *** hypertrophy and myocardial fibrosis remains as the structural and morphological focus in this *** intervention in asymptomatic aortic stenosis or regurgitation along with individualised management of hypertension and atrial fibrillation is likely to improve patient *** pacing via the His-Purkinje system for conduction abnormalities,further reduction in para-valvular aortic regurgitation along with therapy of angiotensin receptor blockade will improve patient outcome by facilitating hypertrophy regression,LV coordinate contraction,and global vascular *** leaflet thromboses require anticoagulation while impaired access to coronary ostia risks future TAVI-in-TAVI or coronary *** comparable long-term durability and the resolution of TAVI related complications become available,SAVR remains the first choice for lower risk younger patients.

关键词： surgical aortic valve replacement trans-catheter aortic valve implantation left ventricular hypertrophy and fibrosis myocardial force-velocity relationship His-Purkinje pacing renin-angiotensin system inhibitors coronary access impairment

Assessment of research productivity of Arab countries in the field of infectious diseases using Web of Science database

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Infectious Diseases of Poverty 2015年第1期4卷 9-16页

作者： Waleed m Sweileh Samah W Al-Jabi Alaeddin Abuzanat Ansam F Sawalha Adham S AbuTaha mustafa A Ghanim Sa’ed H Zyoud Department of Pharmacology and Toxicology College of Medicine and Health SciencesAn-Najah National UniversityNablusPalestine Department of Clinical and Community Pharmacy College of Medicine and Health SciencesAn-Najah National UniversityNablusPalestine Department of microbiology and Immunology College of Medicine and Health SciencesAn-Najah National UniversityNablusPalestine Department of Biochemistry and Genetics College of Medicine and Health SciencesAn-Najah National UniversityNablusPalestine

Background:To meet the future challenges of infectious diseases and limit the spread of multidrug resistant microorganisms,a better understanding of published studies in the field of infectious diseases is *** objective of this study was to analyze the quantity and quality of research activity in the field of infectious diseases in Arab countries and compare it with that in non-Arab ***:Documents published in Arab countries within the research category of“infectious diseases”were extracted and analyzed using the Web of Science *** data analyzed represent research productivity during the time interval between 1900–***:Worldwide,the total number of documents published in the field of infectious diseases up to 2012 was 227,188.A total of 2,408 documents in the field of infectious diseases were published in Arab countries,which represents 1.06%of worldwide research *** output from Arab countries in the field of infectious diseases was low for ***,approximately a five-fold increase was observed in the past *** countries ranked 56th to 218th on the standard competition ranking(SCR)in worldwide publications in the field of infectious ***,with a total publication of 464(19.27%)documents ranked first among Arab countries,while Kuwait University was the most productive institution with a total of 158(6.56%)*** citation per document published in Arab countries was 13.25 and the h-index was ***(230;9.55%),malaria(223;9.26%),and hepatitis(189;7.8%)were the top three infectious diseases studied as according to the retrieved ***:The present data reveals that some Arab countries contribute significantly to the field of infectious ***,Arab countries need to work harder to bridge the gap in this *** with non-Arab countries in the middle East,research output from Arab countries was high,but more efforts are needed to enhance the quality o

关键词： Bibliometric Infectious diseases Arab world Web of science

DYNAmIC BIFURCATION OF NONLINEAR EVOLUTION EQUATIONS

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Chinese Annals of mathematics,Series B 2005年第2期26卷 185-206页

作者： ma Tian WANG Shouhong Department of mathematics Sichuan UniversityChengdu 610064China Department of mathematics Indiana UniversityBloomingtonIN 47405USA.

The authors introduce a notion of dynamic bifurcation for nonlinear evolution equa- tions, which can be called attractor bifurcation. It is proved that as the control pa- rameter crosses certain critical value, the system bifurcates from a trivial steady state solution to an attractor with dimension between m and m + 1, where m + 1 is the number of eigenvalues crossing the imaginary axis. The attractor bifurcation theory presented in this article generalizes the existing steady state bifurcations and the Hopf bifurcations. It provides a uni?ed point of view on dynamic bifurcation and can be applied to many problems in physics and mechanics.

关键词： Attractor bifurcation Steady state bifurcation Dynamic bifurcation Hopf bifurcation Nonlinear evolution equation

环泊酚复合舒芬太尼用于不同人群胃镜检查的半数有效剂量

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中国现代应用药学 2024年第12期41卷 1717-1722页

作者：潘敏范正达左小明王程马静谢伟斌常州市第三人民医院药事科江苏常州213001 常州市第三人民医院内镜中心江苏常州213001 常州市第三人民医院麻醉科江苏常州213001

目的测定并比较环泊酚用于不同性别、不同年龄的患者进行无痛胃镜检查时的半数有效剂量(median effective dose,ed_(50))。方法选择2023年3~4月拟行胃镜检查或治疗的患者,按分层随机法纳入4组:第1组中青年男性患者,第2组中青年女性患者,... 详细信息

目的测定并比较环泊酚用于不同性别、不同年龄的患者进行无痛胃镜检查时的半数有效剂量(median effective dose,ed_(50))。方法选择2023年3~4月拟行胃镜检查或治疗的患者,按分层随机法纳入4组:第1组中青年男性患者,第2组中青年女性患者,第3组老年男性患者,第4组老年女性患者。所有患者均先静脉注射0.1μg·kg^(-1)的舒芬太尼。4组患者的环泊酚起始剂量均为0.4 mg·kg^(-1),相邻剂量比值为1:1.1。待患者睫毛反射消失后行胃镜检查,根据Dixon改良序贯法,若前一位患者在进镜过程中出现阳性反应(呛咳、皱眉、体动等),则该组的下一位患者接受环泊酚的剂量递增10%;否则判为阴性反应,该组的下一位患者接受环泊酚的剂量递减10%。将阳性反应转为阴性反应定义为转折点,每组出现7个转折点时终止该组试验。同时记录4组患者在胃镜检查中,不同时间点的血流动力学参数、血氧饱和度以及发生的不良反应。采用Probit回归分析法分别计算4组患者使用环泊酚的ed_(50),并进行组间比较。结果环泊酚复合0.1μg·kg^(-1)舒芬太尼用于中青年男性、中青年女性、老年男性和老年女性患者胃镜检查的ed_(50)分别为0.409、0.373、0.356、0.327 mg·kg^(-1)。中青年男性组环泊酚的ed_(50)显著高于中青年女性组和老年男性组(Ped_(50);显著低于中青年女性组和老年男性组(Ped_(50)不同,女性患者低于男性患者,老年患者低于中青年患者。

关键词：环泊酚舒芬太尼胃镜半数有效剂量(ed_(50)) 量效关系