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New contributions to the phylogeny of the ciliate class Heterotrichea(Protista,Ciliophora):analyses at family-genus level and new evolutionary hypotheses

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Science China(Life Sciences) 2021年第4期64卷 606-620页

作者： Yong Chi Xiangrui Chen Yuqing Li Chundi Wang Tengteng Zhang Alex Ayoub Alan warren Weibo Song Yuanyuan Wang Instiue of Evoluion&Marine Biodiversity and College of Fisheries Ocean University of ChinaQingdao 266003China School of Marine Sciences Ningbo University Ningbo 315211China Department of Pathology University of MichiganAnn Arbor M148109USA Deparmen of Life Sciences Narural Histony MuseumLondon SW75BDUK Laboratory for Marine Biology&Biotechnologr.Qingdao National Laboratory for Marine Science and TechnologyQingdao 266003China College of Marine Life Sciences Ocean Universiy of ChinaQingdao 266003.China

Heterotrichous ciliates play an important role in aquatic ecosystem energy flow processes and many are model organisms for research in cytology,regenerative biology,and *** the present study,we combine both morphological and molecular data to infer phylogenetic relationships at family-genus level and propose new evolutionary hypotheses for the class *** main results include:(1)96 new ribosomal DNA sequences from 36 populations,representing eight families and 13 genera,including three poorly annotated genera,Folliculinopsis,Ampullofolliculina and Linostomella;(2)the earliest-branching families are Spirostomidae in single-gene trees and Peritromidae in the concatenated tree,but the family Peritromidae probably represents the basal lineage based on its possession of many"primitive"morphological characters;(3)some findings in molecular trees are not supported by morphological evidence,such as the family Blepharismidae is one of the most recent branches and the relationship between Fabreidae and Folliculinidae is very close;(4)the systematic positions of Condylostomatidae,Climacostomidae,and Gruberiidae remain uncertain based either on morphological or molecular data;and(5)the monophyly of each genus included in the present study is supported by the molecular phylogenetic trees,except for Blepharisma in the SSU r DNA tree and Folliculina in the ITS1-5.8 S-ITS2 tree.

关键词： evolutionary hypothesis molecular cladogram morphological cladogram multi-gene systematic relationship

ExaHDF5: Delivering Efficient Parallel I/O on Exascale Computing Systems

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Journal of Computer Science & Technology 2020年第1期35卷 145-160页

作者： Suren Byna M.Scot Breitenfeld Bin Dong Quincey Koziol Elena Pourmal Dana Robinson Jerome Soumagne Houjun Tang Venkatram Vishwanath Richard warren Lawrence Berkeley National Laboratory BerkeleyCA 94597U.S.A The HDF Group ChampaignIL 61820U.S.A Argonne National Laboratory LemontIL 60439U.S.A

Scientific applications at exascale generate and analyze massive amounts of data.A critical requirement of these applications is the capability to access and manage this data efficiently on exascale *** I/O,the key technology enables moving data between compute nodes and storage,faces monumental challenges from new applications,memory,and storage architectures considered in the designs of exascale *** the storage hierarchy is expanding to include node-local persistent memory,burst buffers,etc.,as well as disk-based storage,data movement among these layers must be *** I/O libraries of the future should be capable of handling file sizes of many terabytes and *** this paper,we describe new capabilities we have developed in Hierarchical Data Format version 5(HDF5),the most popular parallel I/O library for scientific ***5 is one of the most used libraries at the leadership computing facilities for performing parallel I/O on existing HPC *** state-of-the-art features we describe include:Virtual Object Layer(VOL),Data Elevator,asynchronous I/O,full-featured single-writer and multiple-reader(Full SWMR),and parallel *** this paper,we introduce these features,their implementations,and the performance and feature benefits to applications and other libraries.

关键词： parallel I/O Hierarchical Data Format version 5(HDF5) I/O performance virtual object layer HDF5 optimizations

血管内皮干细胞动员剂对糖尿病小鼠颅骨缺损愈合的影响

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中华整形外科杂志 2011年第6期27卷 442-447页

作者：王晓霞 Stephen warren 北京大学口腔医院口腔颌面外科北京100086 纽约大学医学中心整形与重建外科研究所

目的探讨血管内皮干细胞（endothelial pregenitor cell，EPC）动员剂AMD3100对糖尿病小鼠颅骨缺损愈合的影响。方法2型糖尿病小鼠55只，随机分为未手术组（n=5）、实验组（n=25）和对照组（n=25）。实验组和对照组均在其颅骨表面制造2... 详细信息

目的探讨血管内皮干细胞（endothelial pregenitor cell，EPC）动员剂AMD3100对糖尿病小鼠颅骨缺损愈合的影响。方法2型糖尿病小鼠55只，随机分为未手术组（n=5）、实验组（n=25）和对照组（n=25）。实验组和对照组均在其颅骨表面制造2个直径3mm圆形骨缺损，实验组于术后第3天起给予AMD3100腹腔注射，每日10mg／kg，共15d，对照组给予生理盐水腹腔注射。未手术组处死5只小鼠，实验组和对照组分别于术后1、2、4、8、12周时处死5只小鼠，取外周血测量术前及术后7、14d小鼠血液EPC含量；取颅骨标本，对术后第4、8、12周标本行micro—CT检查，测量计算骨缺损愈合百分比；对所有标本的脱钙石蜡切片进行HE染色，对术后第1、2、4周标本的冰冻切片行CD31和骨钙素免疫荧光染色，计算成骨区血管密度和成骨细胞密度。采用t检验对数据进行统计学分析。结果糖尿病小鼠EPC的动员在创伤后1周基本消失，而AMD3100可显著增高创伤后期血液中EPC水平。AMD3100治疗的糖尿病小鼠在术后第8周和第12周时其骨缺损愈合百分比分别为50．5％、50．9％，均高于对照组的34．8％、40．2％，差异具有统计学意义（P〈0．05）；实验组成骨区血管密度和成骨细胞密度在术后1、2、4周均较对照组增加2倍左右，以术后第2周最显著（实验组毛细血管密度2．47％，成骨细胞密度1．22％；对照组分别是6．11％、2．81％）。结论AMD3100可通过增加成骨区血管密度和成骨细胞密度而改善糖尿病小鼠颅骨缺损愈合程度。

关键词：血管内皮干细胞骨愈合 AMD3100 小鼠肥胖

Strongest Proof Yet of Water Flow on Mars

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科技英语学习 2007年第2期 7-9页

作者： warren Leary 陈静

近年来的试验表明,火星的地表下存在冰和水汽,这有力地证明了火星上水源的存在。美国国家航空和航天局火星研究太空船在对火星进行10年观察之后,又发现了火山壁上的两个沟槽里有些颜色很浅的沉淀物。科学家推测,这些沉淀物是由水及其它... 详细信息

近年来的试验表明,火星的地表下存在冰和水汽,这有力地证明了火星上水源的存在。美国国家航空和航天局火星研究太空船在对火星进行10年观察之后,又发现了火山壁上的两个沟槽里有些颜色很浅的沉淀物。科学家推测,这些沉淀物是由水及其它物质经由沟槽留下的。虽然证据不是确凿无疑,但是火星上存在液态水这种可能性是令人振奋的,这对于未来太空领域的探索有着十分重要的意义,因为水可以分解成氢和氧,氢可以用作火箭的燃料,而氧可以帮助宇航员在太空呼吸。

关键词： Strongest Proof Yet of Water Flow on Mars 沉淀物

Tolerance of ciliated protozoan Paramecium bursaria (Protozoa, Ciliophora) to ammonia and nitrites

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Chinese Journal of Oceanology and Limnology 2005年第3期23卷 349-353页

作者：许恒龙宋微波路璐 warren Alan The Key Laboratory of Mariculture of the Education Ministry Ocean University of China Qingdao 266003 China Department of Biology Liaocheng University Liaocheng 252059 China Department of Zoology Natural History Museum Cromwell Road London SW7 5BD UK China

The tolerance to ammonia and nitrites in freshwater ciliate Paramecium bursaria was measured in a conventional open system. The ciliate was exposed to different concentrations of ammonia and nitrites for 2h and 12h in order to determine the lethal concentrations. Linear regression analysis revealed that the 2h-LC50 value for ammonia was 95.94 mg/L and for nitrite 27.35 mg/L using probit scale method (with 95% confidence intervals). There was a linear correlation between the mortality probit scale and logarithmic concentration of ammonia which fit by a regression equation y=7.32x–9.51 (R2=0.98; y, mortality probit scale; x, logarithmic concentration of ammonia), by which 2 h–LC50 value for ammonia was found to be 95.50 mg/L. A linear correla- tion between mortality probit scales and logarithmic concentration of nitrite is also followed the regression equa- tion y=2.86x+0.89 (R2=0.95; y, mortality probit scale; x, logarithmic concentration of nitrite). The regression analysis of toxicity curves showed that the linear correlation between exposed time of ammonia-N LC50 value and ammonia-N LC50 value followed the regression equation y=2 862.85e-0.08x (R2=0.95; y, duration of exposure to LC50 value; x, LC50 value), and that between exposed time of nitrite-N LC50 value and nitrite-N LC50 value followed the regression equation y = 127.15e-0.13x (R2=0.91; y, exposed time of LC50 value; x, LC50 value). The results demonstrate that the tolerance to ammonia in P. bursaria is considerably higher than that of the larvae or juveniles of some metozoa, e.g. cultured prawns and oysters. In addition, ciliates, as bacterial predators, are likely to play a positive role in maintaining and improving water quality in aquatic environments with high-level ammonium, such as sewage treatment systems.

关键词：纤毛原生动物氨水亚硝酸盐容许量毒物学

High-throughput discovery of fluoride-ion conductors via a decoupled,dynamic,and iterative(DDI)framework

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npj Computational Materials 2022年第1期8卷 983-991页

作者： Jack D.Sundberg Daniel L.Druffel Lauren M.McRae Matthew G.Lanetti Jacob T.Pawlik Scott C.warren Department of Chemistry The University of North Carolina at Chapel HillChapel HillNC27599United States

Fluoride–ion batteries are a promising alternative to lithium–ion batteries with higher theoretical capacities and working voltages,but they have experienced limited success due to the poor ionic conductivities of known electrolytes and ***,we report a high-throughput computational screening of 9747 fluoride-containing materials in search of fluoride-ion *** a combination of empirical,lightweight DFT,and nudged elastic band(NEB)calculations,we identified>10 crystal systems with high fluoride *** applied a search strategy where calculations are performed in any order(decoupled),computational resources are reassigned based on need(dynamic),and predictive models are repeatedly updated(iterative).Unlike hierarchical searches,our decoupled,dynamic,and iterative framework(DDI)began by calculating high-quality barrier heights for fluoride-ion mobility in a large and diverse group of *** high-quality dataset provided a benchmark against which a rapid calculation method could be *** accurate method was then used to measure the barrier heights for 6797 fluoride–ion *** final dataset has allowed us to discover many fascinating,high-performance conductors and to derive the design rules that govern their *** materials will accelerate experimental research into fluoride–ion batteries,while the design rules will provide an improved foundation for understanding ionic conduction.

关键词： fluoride dynamic repeatedly

Adult bobcat(Lynx rufus)habitat selection in a longleaf pine savanna

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Ecological Processes 2018年第1期7卷 206-217页

作者： Andrew R.Little L.Mike Conner Michael J.Chamberlain Nathan P.Nibbelink Robert J.warren Warnell School of Forestry and Natural Resources University of Georgia180 E.Green StAthensGA 30602USA Joseph W.Jones Ecological Research Center at Ichauway NewtonGeorgia 39870USA

Background:Pine savannas are primarily managed with frequent prescribed fire(≤3 years)to promote diversity of flora and fauna,and to maintain open,park-like conditions needed by species such as the endangered red-cockaded woodpecker(Picoides borealis).However,a knowledge gap exists in our understanding of bobcat(Lynx rufus)habitat selection in longleaf pine savannas and research is warranted to direct our future management ***:We examined bobcat habitat selection in a pine savanna managed with frequent fires at two spatial scales(i.e.,study area boundary[hereafter,landscape scale])and annual area of use[95%kernel density;local scale],and assessed effects of prescribed fire on bobcat habitat ***,we monitored 45 bobcats(16 males and 29 females)during 2001–***:We found differential habitat selection by *** the landscape scale,female bobcats were closer to mixed pine-hardwoods,young pine,and secondary roads,but farther from mature pine and hardwoods stands relative to *** found no difference in selection of agriculture,shrub-scrub,and primary roads between *** the annual area of use scale,female bobcats were closer to secondary roads,but farther from agriculture and shrub-scrub relative to *** found no difference in selection of mature pine,mixed pine-hardwoods,hardwoods,young pine,and primary roads between *** primarily selected for stands burned≤1.1 years ***:Our results show that bobcats exploit a broad range of habitat types in pine landscapes managed with frequent fire and commonly use recently burned stands(≤1.1 year post-fire),suggesting prey in many areas of this system are at risk of bobcat ***,we suggest land managers consider scale of selection by bobcats when developing habitat management strategies.

关键词： Georgia Habitat selection Lynx rufus Pinus palustris Prescribed fire

MiR-130a regulates and dendritic spine MeCP2 neurite outgrowth density by targeting

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Protein & Cell 2016年第7期7卷 489-500页

作者： Yunjia Zhang Mengmeng Chen Zilong Qiu Keping Hu warren McGee Xiaoping Chen Jianghong Liu Li Zhu Jane Y. Wu State Key Laboratory for Brain & Cognitive Science Institute of Biophysics Chinese Academy of Sciences Beijing 100101 China University of Chinese Academy of Sciences Beijing 100049 China Laboratory of Molecular Basis of Neural Plasticity Institute of Neuroscience Chinese Academy of Sciences Shanghai 200031 China Institute of Medicinal Plant Development (IMPLAD) Chinese Academy of Medical Sciences Beijing 100193 China Department of Neurology Center for Genetic Medicine Lurie Cancer Center Northwestern University Feinberg School of Medicine Chicago IL 60611 USA

MicroRNAs （miRNAs） are critical for both development and function of the central nervous system. Significant evidence suggests that abnormal expression of miRNAs is associated with neurodevelopmental disorders. MeCP2 protein is an epigenetic regulator repressing or activating gene transcription by binding to methylated DNA. Both loss-of-function and gain-of-function muta- tions in the MECP2 gene lead to neurodevelopmental disorders such as Rett syndrome, autism and MECP2 duplication syndrome. In this study, we demonstrate that miR-130a inhibits neurite outgrowth and reduces dendritic spine density as well as dendritic complexity. Bioinformatics analyses, cell cultures and biochemical experiments indicate that miR-130a targets MECP2 and down-regulates MeCP2 protein expression. Further- more, expression of the wild-type MeCP2, but not a loss- of-function mutant, rescues the miR-130a-induced phe- notype. Our study uncovers the MECP2 gene as a pre- vious unknown target for miR-130a, supporting that miR-130a may play a role in neurodevelopment by reg- ulating MeCP2. Together with data from other groups,our work suggests that a feedback regulatory mecha- nism involving both miR-130a and MeCP2 may serve to ensure their appropriate expression and function in neural development.

关键词： miR-130a MECP2 neurite outgrowth,dendritic spines dendrite morphology

Impact of Friction Stir Welding (FSW) Process Parameters on Thermal Modeling and Heat Generation of Aluminum Alloy Joints

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Acta Metallurgica Sinica(English Letters) 2016年第9期29卷 869-883页

作者： Saad B.Aziz Mohammad W.Dewan Daniel J.Huggett Muhammad A.Wahab Ayman M.Okeil T.warren Liao Department of Mechanical and Industrial Engineering Louisiana State University Department of Civil and Environmental Engineering Louisiana State University

Friction stir welding （FSW） is a solid-state joining process, where joint properties largely depend on the amount of heat generation during the welding process. The objective of this paper was to develop a numerical thermomechanical model for FSW of aluminum--copper alloy AA2219 and analyze heat generation during the welding process. The thermomechanical model has been developed utilizing ANSYS APDL. The model was verified by comparing simulated temperature profile of three different weld schedules （i.e., different combinations of weld parameters in real weld situations） from simulation with experimental results. Furthermore, the verified model was used to analyze the effect of different weld parameters on heat generation. Among all the weld parameters, the effect of rotational speed on heat generation is the highest.

关键词： Friction stir welding Frictional dissipation energy Temperature distribution Friction modeling Aluminum alloy