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Modeling xeroderma pigmentosum associated neurological pathologies with patients-derived iPSCs

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Protein & Cell 2016年第3期7卷 210-221页

作者： lina Fu Xiuling Xu ruotong ren Jun Wu Weiqi Zhang Jiping yang Xiaoqing ren Si Wang yang Zhao liang Sun yang Yu Zhaoxia Wang Ze yang Yun Yuan Jie Qiao Juan Carlos Izpisua Belmonte Jing Qu Guang-Hui liu National laboratory of Biomacromolecules Institute of Biophysics Chinese Academy of Sciences Beijing 100101 China FSU-CAS Innovation Institute Foshan University Foshan 528000 China State Key laboratory of Stem Cell and reproductive Biology Institute of Zoology Chinese Academy of Sciences Beijing 100101 China Gene Expression laboratory Salk Institute for Biological Studies 10010 North Torrey Pines Road La Jolla CA 92037 USA Universidad Cato1ica San Antonio de Murcia (UCAIVI) Campus de los Jer6nimos N° 135 Guadalupe 30107 Murcia Spain Beijing Hospital of the Ministry of Health Beijing 100730 China Department of Gynecology and Obstetrics Peking University Third Hospital Beijing 100191 China Department of Neurology Peking University First Hospital Beijing 100034 China Beijing Institute for Brain Disorders Capital Medical University Beijing 100069 China University of Chinese Academy of Sciences Beijing 100049 China

Xeroderma pigmentosum （XP） is a group of genetic disorders caused by mutations of XP-associated genes, resulting in impairment of DNA repair. XP patients frequently exhibit neurological degeneration, but the underlying mechanism is unknown, in part due to lack of proper disease models. Here, we generated patientspecific induced pluripotent stem cells （iPSCs） harboring mutations in five different XP genes including XPA, XPB, XPC, XPG, and XPV. These iPSCs were further differentiated to neural cells, and their susceptibility to DNA damage stress was investigated. Mutation of XPA in either neural stem cells （NSCs） or neurons resulted in severe DNA damage repair defects, and these neural cells with mutant XPA were hyper-sensitive to DNA damage-induced apoptosis. Thus, XP-mutant neural cells represent valuable tools to clari the molecular mechanisms of neurological abnormalities in the XP patients.

关键词： xeroderma pigmentosum iPSC disease model neural stem cell. neuron

Hemodynamic characteristics in preeclampsia women during cesarean delivery after spinal anesthesia with ropivacaine

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World Journal of Clinical Cases 2020年第8期8卷 1444-1453页

作者： Na Zhao Jin Xu Xiao-Guang li Joseph harold Walline Yi-Chong li lin Wang Guo-Sheng Zhao Ming-Jun Xu Department of Anesthesiology Beijing Obstetrics and Gynecology HospitalCapital Medical UniversityBeijing 100026China Department of Emergency Medicine Peking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100730China Accident and Emergency Medicine Academic Unit Prince of Wales HospitalThe Chinese University of Hong KongHong Kong 9990777China Department of Clinical research and Epidemiology National Clinical Research Center for Cardiovascular DiseasesFuwai HospitalChinese Academy of Medical SciencesBeijing 100037China

BACKGrOUND Very few studies have been published on the hemodynamic changes associated with spinal anesthesia induced with ropivacaine during cesarean deliveries in preeclamptic *** To record and analyze hemodynamic data in women with preeclampsia undergoing cesarean delivery after spinal anesthesia induced with *** Ten eligible women with preeclampsia were enrolled in this prospective observational *** anesthesia was performed with 2.4 ml of 0.5%*** changes were then analyzed at multiple time *** hemodynamic responses to vasopressor interventions and uterotonic agents,as well as maternal and neonatal outcomes were also *** Stable hemodynamic trends were observed in this *** output(CO)and stroke volume increased mildly during *** contrast,mean arterial pressure and systemic vascular resistance showed a moderate decrease from induction until the end of *** venous pressure dramatically increased after *** administration was associated with the most significant hemodynamic fluctuations during surgery,namely,an increase in CO and heart *** intervention was only required in three patients,and caused an increase in mean arterial pressure and systemic vascular resistance along with a decrease in heart rate,stroke volume,and *** maternal and neonatal complications were observed during this study,except transient episodes of *** Spinal anesthesia for caesarian delivery with ropivacaine in women with preeclampsia is linked to modest hemodynamic changes of no clinical significance in this *** cardiovascular monitoring is still recommended,particularly after the delivery of the fetus or the use of oxytocin.

关键词： Preeclampsia Cesarean delivery Spinal anesthesia Cardiac output Hemodynamics

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XMl实用教程

E coli Accumulation behind an Obstacle

丛书名：最新Internet技术基础与应用系列丛书

1999年

作者：（美）（E.r.哈罗德）Elliotte rusty harold 康博创作室译

来源：畅想之星图书光盘版（南... 评论

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Advances in Microbiology 2018年第6期8卷 451-464页

作者： Gastón l.Mino Magali Baabour ricardo Chertcoff Gabriel Gutkind Eric Clément harold Auradou Irene Ippolito lab. de Microscopía Aplicada a Estudios Moleculares y Celulares (lAMAE) Fac. de Ingeniería Univ. Nac. de Entre Ríos (FI-UNER) and Inst. de Investigación y Desarrollo en Bioingeniería y Bioinformática IBB-(UNER-CONICET) Oro Verde Argentina Universidad de Buenos Aires Facultad de Ingeniería Grupo de Medios Porosos Buenos Aires Argentina Universidad de Buenos Aires Facultad de Farmacia y Bioquímica Cátedra de Microbiología Buenos Aires Argentina Physique et Mécanique des Milieux Hétérogénes (UMr 7636 ESPCI/CNrS/Univ. P.M. Curie/Univ. Paris-Diderot) Paris France laboratoire FAST Univ. Paris Sud CNRS Université Paris-Saclay F-91405 Orsay France

This paper describes our findings regarding the accumulation of motile bacteria at the rear of a confined obstacle and the physical description of the mechanisms at play. We found that the modification of flow due to the presence of the obstacle produces vorticity that favor the diffusion of bacteria towards the downstream stagnation point. By testing different flow rates, we determined the range in which bacteria accumulate. More interestingly, we observe that hydrodynamic interaction between the bacteria and the top and bottom surface of the microfluidic chip maintain the bacteria in the region where the flow velocity is lower than their own velocity. In the case of non-motile bacteria, this effect is not observed because bacteria follow the streamlines as passive tracers do.

关键词： E coli Motility Filtration Microfluidic Bacterial Accumulation

Solid phase microextraction(SPME) sampling under turbulent conditions and for the simultaneous collecting of tracer gases

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International Journal of Mining Science and Technology 2015年第4期25卷 559-563页

作者： Underwood Susanne W. Jong Edmund C. luxbacher Kray D. Sarver Emily A. ripepi Nino S. Mc Nair harold M. Department of Mining and Minerals Engineering Virginia Tech Department of Chemistry Virginia Tech

Solid phase microextraction （SPME） is a solvent-flee method of sample collection. SPME is an appealing method for sample collection because it is designed for the sampling of trace level analytes with short sampling times in a variety of environments. Additionally, SPME can be used to directly deliver a sample to a gas chromatograph （GC） for analysis by means of thermal desorption. In this paper, the performance of SPME under dynamic conditions was investigated. Additionally, the competence of SPME sampling for the simultaneous analysis of multiple trace analytes was also evaluated. This work is discussed in the context of underground mine ventilation surveys but is applicable to any industry in which ventilation circuits must be evaluated. The results of this paper showed that the performance of the 100 ~m PDMS SPME fiber was both precise and rapid under dynamic conditions. This SPME fiber was also able to simultaneously collect sulfur hexafluoride （SF6） and perfluoromethylcyclohexane （PMCH） with adequate sensitivity.

关键词： Solid phase microextraction Sulfur hexafluoride Perfluoromethylcyclohexane Tracer gas Mine ventilation Air sampling

The Active Sites and Corresponding Stability Challenges of the M-N-C Catalysts for Proton Exchange Membrane Fuel Cell

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Chinese Journal of Chemistry 2023年第6期41卷 710-724页

作者： ruolin Peng Zhongkun Zhao Hongmin Sun Yongping yang Tinglu Song Yao yang Jiankun Shao Haibo Jin Hongtao Sun Zipeng Zhao Beijing Key laboratory of Construction Tailorable Advanced Functional Materials and Green Applications Experimental Center of Advanced MaterialsSchool of Materials Science and EngineeringBeijing Institute of TechnologyBeijing100081China The harold and Inge Marcus Department of Industrial and Manufacturing Engineering The Pennsylvania State UniversityUniversity ParkPA16802-4400USA School of Engineering Westlake UniversityHangzhouZhejiang 310030China State Key laboratory of Explosion Science and Technology Bejing Institute of TechnologyBeijing 100081China The Materials research institute The Pennsylvania State UniversityUniversityParkPA16802-4400UA

Proton exchange membrane fuel cells(PEMFCs)as promising alternatives to traditional internal combustion engines have attracted massive concerns to promote their wide application in ***,the biggest challenge to the commercialization of PEMFCs remains the high cost due to the adoption of the platinum group metal(PGM)catalysts in the cathode.

关键词： Proton exchange membrane fuel cell Electrocatalysis Oxygen reduction reaction M-N-C catalysts Active sites Stability Degradation mechanisms

Al-Cu-Si合金中的CuAl_2相在固溶处理时的溶解对时效后强度的影响

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材料科学与工艺 2006年第5期14卷 547-551页

作者：张丁非彭建 harold.D.Brody John.E.Morral 重庆大学材料科学与工程学院四川重庆400044 美国康涅狄格州立大学料科学学院 06268

Al-3．5Cu-7．0Si铸造铝合金在固溶处理过程中，随固溶处理时间的延长，时效后的强度显著增加,两次强度增加分别发生在0—2小时和4—8小时，与铸态强度相比，其抗拉强度分别增加50-80MPa和约20MPa.金相观察及扫描电镜分析表明，第一次... 详细信息

Al-3．5Cu-7．0Si铸造铝合金在固溶处理过程中，随固溶处理时间的延长，时效后的强度显著增加,两次强度增加分别发生在0—2小时和4—8小时，与铸态强度相比，其抗拉强度分别增加50-80MPa和约20MPa.金相观察及扫描电镜分析表明，第一次强度增加主要源于依附在杂质上的CuAl2相及基体中弥散的CuAl2相的溶解，硅相粒子的平滑化也对强度提高有一定作用；第二次强度增加则是由于块状CuAl2相开始溶解的贡献．该合金中的富铁化合物特别是β—FeSiAl5相非常稳定，通常的固溶处理难以使其溶解或改变其形状和分布．

关键词： Al-Cu--Si合金固溶处理 CuAl2相溶解强化

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机械传动装置的过盈配合

机械科学与技术 1982年第4期 50-58+69页

作者： harold.r.Johnson 肖尧荣

过盈配合可用于齿轮和滑轮之类的组合传动零件,但当元件数目增加时,分析这些组合件应力的工作很复杂。本文介绍了求受内外压力厚壁筒应力的方法。以此为基础,介绍了不等圆长圆筒和旋转圆筒的应力分析方法。对于元件过盈配合传动装置,用... 详细信息

过盈配合可用于齿轮和滑轮之类的组合传动零件,但当元件数目增加时,分析这些组合件应力的工作很复杂。本文介绍了求受内外压力厚壁筒应力的方法。以此为基础,介绍了不等圆长圆筒和旋转圆筒的应力分析方法。对于元件过盈配合传动装置,用矩阵来求解主应力可使计算简化。

关键词：过盈配合矩阵方程式数学分析方程机械传动装置过盈配合量圆筒体弹性模数

Effects of Different Pre-processing Strategies:a Comparative Study on Decision Tree Algorithms

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Effects of Different Pre-processing Strategies:a Comparative...

作者： harold Buko DADYE 湖南大学

学位级别：硕士

信息技术的增殖和普及极大地丰富了收集数据的途径,使大规模的数据存储成为可能。随着可用数据在规模和复杂性上的不断增长,人与人之间直接的数据分析被间接的自动数据处理不断增强。以往数据挖掘技术主要是由相对复杂的、拥有良好技术... 详细信息

信息技术的增殖和普及极大地丰富了收集数据的途径,使大规模的数据存储成为可能。随着可用数据在规模和复杂性上的不断增长,人与人之间直接的数据分析被间接的自动数据处理不断增强。以往数据挖掘技术主要是由相对复杂的、拥有良好技术背景的“专家”用户所使用,与此不同的是,目前越来越多更加“幼稚”的用户开始使用这些技术来进行决策。这必然需要制定一些规则来指导数据分析师或管理人员根据数据的性质决定使用哪些特定的算法。对数据与处理阶段所使用的不同策略带来的影响的理解有助于制定最佳做法,同时增加模型的价值和精确度。通常米说,数据挖掘技术可以用来对描述性任务进行预测,即基于其他属性的预测值来确定特定属性的预测值,或者派生出一些用于总结数据内部潜在关系的模式。数据挖掘技术是一个嵌入在数据库中的模式自动发现过程。它是一个跨学科技术,融合了统计分析、数据库系统、机器学习、模式识别、神经网络、模糊系统以及其他“软计算”技术。凭借其将数据转换成信息的能力,近些年数据挖掘技术几乎被应用于生活的各个方面,例如商务,市场营销,医疗,电信,银行,基建公司,教育等。核心数据挖掘技术由此可以用于预测性建模,包括分类(当目标类是数字时,可以看成回归)和聚类、关联分析和异常检测。分类和预测是两种形式的数据分析方法,可用于帮助提取模型以描述重要数据类或预测未来的数据趋势,使我们更好地理解数据。一般而言,分类用来预测分类标签,预测模型用来于此连续值型函数。在各种现有的分类算法中,使用归纳学习机制的决策树仍然是目前最流行、最实用和有效的方法。决策树对于构建分类或数据勘探而言确实是首选工具,主要是因为一些因素的影响：1)决策树是简单易懂,并进行简要说明后,因为他们可以很容易地理解;2)决策树在这个意义上没有假设的空间分布和分类结构的非参数;3)能够与缺失值处理的数据集,以及定性数据;4)决策树可以同时处理数值和分类数据,其它技术通常专门用于分析只有一个变吊的数据集类型。例如,关系规则只能应用于名义变量,而类神经网络只于数值变量共事。5)他们产生更好的精度,并无疑是强大的,即使当他们的假设是有点违反了真实模型产生的数据,他们仍旧表现良好。虽然各种各样的决策树算法已经被开发出来,常见的决策树算法的基本实现的基础上只是几个算法,本文称之为“传统”的算法,包括ID3,其继任者的C4.5车和CHAID。然而,它对考虑的概率计算方法,因为它使用卡方统计量来确定最佳分裂属性,因此,通常使用的统计软件包,例如STATISTICA。这里被称为传统的方法,以巩固存在一些决策树算法的改进和实现较为先进的这些基本决定树实现。这些领先的方法已确定与传统的算法克服一些特定的缺点。本文旨在重点分析在预加工过程中不同的策略对决策树算法性能的影响,从而开改进价值及模型精度的最佳方式。这可以通过对其表现进行调查,根据现有数据类型、数据分布、数据丢失现象、如何处理这样的数据集以发展为同一分类、采用不同的离散化数据的策略带来的影响、不同特征降维技术、效率和可扩展性问题等等,从而开展比较评估分析。本文进行了比较评估分析实验,并对最前沿的分类和预测算法进行了调查和简要讨论。对有关分类和预测以及构建分类器的一些重大问题进行了认定和处理,得出以下主要成果：1.简单的决策树可以被用来模仿其他分类器的性能,并有相当不错的表现,使其成为初始用户或者数据探索的早期阶段的不二选择。2.由于其简单、执行时间短、与负载呈线性比例关系、相对较小规模的树便可以提高其可理解性等性能,将ID3与正确的预加工方法想结合可以成为用于探索新的数据的重要工具。3.另一方面,离散化确实能影响到所得模型的性能,因此它总是需要通过类分布来完成。4.离散也可以用于克服在使用C4.5中对信息分割的需要,从而处理许多相应的分割值。因此,在完成缺失值的离散化和更换基础上,ID3可以轻易被用于估计C4.5算法的性能。5.所有传统的树算法似乎在性能方面都遵循相同的模式,这表明任一传统方法是其他算法运行的代表。因此,如果一个较低的性能被登记在一种算法里,那么其他高级的算法也应该被整理。6.不同决策树算法的性能,在准确度方面都是与属性数量以及分类属性值相互独立的。7.当数据足够大时,通过属性约简技术可以实现近似并在技术选择上具有更大的灵活性。8.丢失数据的替代应根据给定属性的模态值(对整个数据集而言),与所在类无关。在本研究领域未来的发展方向主要有两点。第一,在该领域的研究应着眼于开发一些概念,可以在不同决策树算法的运用中提供指导,并考虑到数据集所包含的数据类型,依据目前属性或者实例数量得出的分布及规模。第二,可以开展更多的实验来调查预处理、数据清理以及替换缺失值的性能,在建立在不替换基础上的统计方法并通过使用数据集中的所有类的模态属性值来完成,有机

关键词：决策树数据挖掘分类算法决策支持系统数据预处理