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Stem Cel. Discovery 2012年第4期2卷 163-175页

作者： Margaret l. Shirl.y Al.son Venabl. Raj R. Rao Nol.n l. Boyd steven l. Stice David Puett Prema Narayan Cardiovascul.r Innovation Institute University of Louisville Louisville USA Department of Biochemistry and Mol.cul.r Biol.gy University of Georgia Athens USA Department of Chemical.and l.fe Science Engineering School of Engineering Virginia Commonwealth University Richmond USA Department of Physiol.gy Southern Illinois University School of Medicine Carbondale USA

Human embryonic stem cel.s (hESC) can be induced to differentiate to trophobl.st by bone morphogenetic proteins (BMPs) and by aggregation to form embryoid bodies (EB), but there are many differences and controversies regarding the nature of the differentiated cel.s. Our goal. herein were to determine if BG02 cel.s form trophobl.st-l.ke cel.s (a) in the presence of BMP4-pl.s-basic fibrobl.st growth factor (FGF-2) and (b) upon EB formation, and (c) whether the BMP4 antagonist noggin el.cits direct effects on gene expression and hormone production in the cel.s. Transcriptome profil.ng of hESC incubated with BMP4/FGF-2 showed a down-regul.tion of pl.ripotency-associated genes, an up-regul.tion of trophobl.st-associated genes, and either a down-regul.tion or no change in gene expression for many markers of the three embryonic germ l.yers. Yet, there was up-regul.tion of several.genes associated with mesoderm, ectoderm, and endoderm, strongl. suggesting that differentiation to trophobl.st-l.ke cel.s under the conditions used does not yiel. a homogeneous cel. type. Several.genes, heretofore unreported, were identified that are al.ered in hESC in response to BMP4-mediated differentiation. The production of human chorionic gonadotropin (hCG), progesterone, and estradiol.in the differentiated cel.s confirmed that trophobl.st-l.ke cel.s were obtained. Gene expression by EB was characterized by an up-regul.tion of a number of genes associated with trophobl.st, ectoderm, endoderm, and mesoderm, and the production of hCG and progesterone confirmed that trophobl.st-l.ke cel.s were formed. These resul.s suggest that, in the presence of FGF-2, BG02 cel.s respond to BMP4 to yiel. trophobl.st-l.ke cel.s, which are al.o obtained upon EB formation. Thus, BMP4-mediated differentiation of hESC represents a viabl. cel. system for studying earl. devel.pmental.events post-impl.ntation;however, up-regul.tion of non-trophobl.st genes suggests a somewhat diverse response to BMP4/FGF-2. Noggin a

关键词： Human Embryonic Stem Cel.s Trophobl.sts Bone Morphogenetic Protein-4 Embryoid Bodies Noggin

An integrative mul.ivariate approach for predicting functional.recovery using magnetic resonance imaging parameters in a transl.tional.pig ischemic stroke model

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Neural.Regeneration Research 2021年第5期16卷 842-850页

作者： Erin E.Kaiser J.C.Poythress Kel.y M.Scheul.n Brian J.Jurgiel.wicz Nicol. A.l.zar Cheol.oo Park steven l.Stice Jeongyoun Ahn Frankl.n D.West Regenerative Bioscience Center University of GeorgiaAthensGAUSA Neuroscience Biomedical and Health Sciences InstituteUniversity of GeorgiaAthensGAUSA Department of Animal.and Dairy Science College of Agricultural and Environmental SciencesUniversity of GeorgiaAthensGAUSA Department of Statistics Franklin College of Arts and SciencesUniversity of GeorgiaAthensGAUSA

Magnetic resonance imaging(MRI)is a cl.nical.y rel.vant,real.time imaging modal.ty that is frequentl. util.zed to assess stroke type and ***,specific MRI biomarkers that can be used to predict l.ng-term functional.recovery are stil. a critical.***,the present study sought to examine the prognostic val.e of commonl. util.zed MRI parameters to predict functional.outcomes in a porcine model.of ischemic *** was induced via permanent middl. cerebral.artery *** 24 hours post-stroke,MRI anal.sis reveal.d focal.ischemic l.sions,decreased diffusivity,hemispheric swel.ing,and white matter *** deficits incl.ding behavioral.abnormal.ties in open fiel. and novel.object expl.ration as wel. as spatiotemporal.gait impairments were observed at 4 weeks *** graphical.model. identified specific MRI outputs and functional.recovery variabl.s,incl.ding white matter integrity and gait performance,that exhibited strong conditional.*** correl.tion anal.sis reveal.d a prognostic rel.tionship between l.sion vol.me and white matter integrity and novel.object expl.ration and gait ***,these anal.ses may al.o have the potential.of predicting patient recovery at chronic time points as pigs and humans share many anatomical.simil.rities(e.g.,white matter composition)that have proven to be critical.in ischemic stroke *** study was approved by the University of Georgia(UGA)Institutional.Animal.Care and Use Committee(IACUC;Protocol.Number:A2014-07-021-Y3-A11 and 2018-01-029-Y1-A5)on November 22,2017.

关键词： behavior testing canonical.correl.tion anal.sis gait anal.sis Gaussian graphical.model. ischemic stroke magnetic resonance imaging pig model principal.component anal.sis

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Determination of Particul.te Matter Emissions from Cattl. Feedl.ts Using Wind-Trax and the Fl.x-Gradient Technique

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Journal.of Environmental.Protection 2016年第2期7卷 176-189页

作者： Henry F. Bonifacio Ronal.o G. Maghirang steven l. Trabue l.ura l. McConnel. John H. Prueger Edna R. Bonifacio Pasture Systems and Watershed Management Research Unit USDA Agricultural Research Service University Park PA USA Department of Biol.gical.and Agricul.ural.Engineering Kansas State University Manhattan KS USA National.l.boratory of Agricul.ure and the Environment USDA Agricultural Research Service Ames IA USA Bayer Crop Science 2 T.W. Alexander Dr. Research Triangle Park NC USA

l.rge commercial.cattl. feedl.ts are significant sources of particul.te matter (PM) emissions. This research compared WindTrax and the fl.x-gradient technique in estimating emissions of PM with aerodynamic diameter 10) from cattl. feedl.ts. Meteorol.gical.conditions were measured and PM10 concentrations were profil.d vertical.y (i.e., 2.0 to 7.62 m) at a l.rge commercial.beef cattl. feedl.t in Kansas from May through September 2011. Resul.s show that between the two methods eval.ated, WindTrax was l.ast sensitive to changes in heights and number of heights used in the emission estimation, with cal.ul.ted PM10 emission rates varying by up to 18% onl.. On the other hand, PM10 emission rates produced by the fl.x-gradient technique varied by al.ost 56% when changing either heights and/or number of heights in emission cal.ul.tion. Both methods were sensitive to height settings, with their respective PM10 emission rates higher when the l.west height setting (2.0 m) was incl.ded. Cal.ul.ting PM10 emission rates with the 7.62-m height l.d to l.wer estimates for the fl.x-gradient technique but no significant change in estimates was observed for WindTrax. As demonstrated in this study, for the fl.x-gradient technique, settings for the l.west and highest heights were the most critical.in emission estimation;excl.sion of other heights in between showed onl. to 2% to 6% change in cal.ul.ted PM10 emission rates. In general. the higher PM10 emission rates were obtained with the fl.x-gradient technique. However, el.minating the l.west height (2.0 m) in the cal.ul.tion and, at the same time, using a specific set of formul.tions for the fl.x-gradient technique made its cal.ul.ted PM10 emission rates sl.ghtl. l.wer (but not significantl. different) than those from WindTrax.

关键词： PM10 Emission Rates Cattl. Feedl.ts Emission Rate Estimation WindTrax Fl.x-Gradient Technique

Porosity Effects on Interl.minar Fracture Behavior in Carbon Fiber-Reinforced Pol.mer Composites

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Material. Sciences and Appl.cations 2017年第2期8卷 170-187页

作者： Issa A. Hakim steven l. Donal.son Norbert G. Meyendorf Charl.s E. Browning Department of Mechanical.& Aerospace Engineering University of Dayton Dayton OH USA Fraunhofer-IKTS Berlin Germany Department of Mechanical.Engineering Omar Al-Mukhtar University El-Beida Libya Department of Civil.& Environment Engineering & Engineering Mechanics University of Dayton Dayton OH USA Department of Aerospace Engineering Iowa State University Ames IA USA Department of Chemical.& Material. Engineering University of Dayton Dayton OH USA

Fiber-reinforced pol.mer composite material. have become material. of choice for manufacturing appl.cation due to their high specific stiffness, strength and fatigue l.fe, l.w density and thermal.expansion coefficient. However, there are some types of defects such as porosity that form during the manufacturing processes of composites and al.er their mechanical.behavior and material.properties. In his study, hand l.y-up was conducted to fabricate sampl.s of carbon fiber-reinforced pol.mer composites with three different vacuum l.vel. in order to vary porosity content. Nondestructive eval.ation, destructive techniques and mechanical.testing were conducted. Nondestructive eval.ation resul.s showed the trend in percentages of porosity through-thickness. Serial.sectioning images reveal.d significant detail. about the composite’s internal.structure such as the vol.me, morphol.gy and distribution of porosity. Mechanical.testing resul.s showed that porosity l.d to a decrease in both Mode I static interl.minar fracture toughness and Mode I cycl.c strain energy rel.ase rate fatigue l.fe. The fractographic micrographs showed that porosity content increased as the vacuum decreased, and it drew a rel.tionship between fracture mechanisms and mechanical.properties of the composite under different modes of l.ading as a resul. of the porosity effects. Final.y, in order to accuratel. quantify porosity percentages incl.ded in the sampl.s of different vacuum l.vel., a comparison was made between the parameters and percentages resul.ed from the nondestructive eval.ation and mechanical.testing and the features resul.ed from fractography and serial.sectioning.

关键词： Carbon Fiber Reinforced Composite Nondestructive Eval.ation Porosity Fatigue Fracture Behavior Serial Sectioning

Winning Debates《赢在辩论》

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英语学习 2012年第7期 65-68页

作者： steven l. Johnson 美国阿拉斯加大学辩论系

作者***是美国阿拉斯加大学辩论系的副教授。作为全美最大的辩论机构——美国议会制辩论联盟（NPDA，National.Parl.amentary Debate Association）的首任主席，steven多年来活跃于世界大学生辩论赛舞台，并一直担任世界大学生辩论赛秘... 详细信息

作者***是美国阿拉斯加大学辩论系的副教授。作为全美最大的辩论机构——美国议会制辩论联盟（NPDA，National.Parl.amentary Debate Association）的首任主席，steven多年来活跃于世界大学生辩论赛舞台，并一直担任世界大学生辩论赛秘书长一职。他指导的队伍曾在各种国际比赛中多次获奖。自2005年以来，steven一直担任“外研社杯”全国英语辩论赛总裁判长。

关键词：辩论赛 Johnson 大学生阿拉斯加副教授议会制秘书长美国

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陆上地震勘探数据处理

石油物探译丛 1990年第1期 60-66页

作者： steven l. Roche 王宝祥

在采集和处理过程中,对地层信息反射地震数据的利用需要对数据的相位和振幅作仔细考虑。地层勘探有一种方法就是计算地质模型的地震响应。经常使用一个零相位子波并对最终得出的道的振幅和相位均作了周密检查。对地震数据与模型道相符... 详细信息

在采集和处理过程中,对地层信息反射地震数据的利用需要对数据的相位和振幅作仔细考虑。地层勘探有一种方法就是计算地质模型的地震响应。经常使用一个零相位子波并对最终得出的道的振幅和相位均作了周密检查。对地震数据与模型道相符的程度作了认真的研究。本文对采集方法以及用于得出零相位,相对振幅剖面的处理流程作了描述。振幅问题为本文要具体讨论的话题。反射相对振幅的保持是通过计算和应用一套表层一致的道标定来完成的。处理陆上数据,特别是将要叙述的可控震源数据在取得相对振幅剖面中所出现的困难颇多,包括耦合效应及震源产生的噪声。震源耦合以及接收器耦合的变化直接影响着反射数据的振幅。来自诸如地滚波及空气波等产生的干扰限制了“标定”时窗的能力,致使不能正确计及震源耦合和接收器耦合。应用地表一致标定和球面发散校正可产生一个相对振幅叠加。然而,该叠加并不必然是最佳的信噪比叠加。大的振幅,震源产生的噪声以及随机环境噪声会通过共中心点(CMP)叠加处理造成叠加剖面质量下降。 CMP相异叠加(DIVERSITY STACK)可衰减那些在CMP道集内的振幅大和时间,空间可变的干扰。在通过耦合校正标定来取得恒定的反射信号振幅后,相异叠加可被证明为接近最佳信噪比叠加的真振幅处理。

关键词：陆上地震勘探数据处理震源耦合检测器

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常规威慑新技术的作战局限性

现代防御技术 1986年第1期 20-29页

作者： steven l. Canbn 金仁源

《国际防御评论》杂志(IDR)1985年第5期上,James ***博士提出了使用ET技术的理由,以便扩大常规武器攻击敌人后方的能力,从而在未来的欧洲战场中避免采用核武器。在本文申steven Canby博士一方面承认这个技术的潜力,同时又就它的作战可... 详细信息

《国际防御评论》杂志(IDR)1985年第5期上,James ***博士提出了使用ET技术的理由,以便扩大常规武器攻击敌人后方的能力,从而在未来的欧洲战场中避免采用核武器。在本文申steven Canby博士一方面承认这个技术的潜力,同时又就它的作战可行性提出了严峻的问题。《国际防御评论》IDR认为加强欧洲常规成慑力量的趋势是极为重要的,因此倾听各种不同的意见,进行讨论是有益无害的。

关键词： ET 弹头苏联末制导 IDR 战斗部苏维埃社会主义共和国联盟末端制导北约部队杀伤概率常规

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抗生素治疗的争议

药学实践与服务 1987年第2期 13-15页

作者： steven l. Barriere 顾晓晨密执安大学药学院药学副教授美国

1984年全美医院中15种销售最多的药品中有10种为抗生素,即头孢甲氧霉素(Cefoxitin)、头孢羟唑(cefamandol.)、氯林可霉素(cl.ndamycin)、头孢噻肟(cefotaxime)、头孢唑啉(cefazol.n)、妥布霉素(tobramycin)、万古霉素(vancomycin)、阿霉素(doxorubicin)、头孢氧哌唑(cefoperazone)、哔哌青霉素(piperacil.in),且多数为近几年出现的新抗生素。这10种药品的年销售总量达十亿美元。

关键词：抗生素治疗给药方法治疗效果氨基糖碳水化合物内酞胺类抗生素致病菌病原微生物新抗生素氯林可霉素 PAE 革兰氏阴性杆菌革兰阴性杆菌青霉素抗菌素治疗方案

Formation of Pl.tinum (Pt) Nanocl.ster Coatings on K-OMS-2 Manganese Oxide Membranes by Reactive Spray Deposition Technique (RSDT) for Extended Stabil.ty during CO Oxidation

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Advances in Chemical.Engineering and Science 2014年第1期4卷 23-35页

作者： Hector F. Garces Justin Rol.er Cecil.K. King’ondu Saminda Dharmarathna Roger A. Ristau Rishabh Jain Radenka Maric steven l. Suib Department of Chemistry University of Connecticut Storrs USA Department of Chemistry University of Connecticut Storrs USA Institute of Material. Science University of Connecticut Storrs USA Department of Material. Science & Engineering University of Connecticut Storrs USA Center for Cl.an Energy Engineering University of Connecticut Storrs USA Department of Material. Science & Engineering University of Connecticut Storrs USA Center for Cl.an Energy Engineering University of Connecticut Storrs USA Chemical.and Biomol.cul.r Engineering Department University of Connecticut Storrs US Department of Sustainabl. Energy Science and Engineering Nelson Mandela African Institution of Science and Technology Arusha Tanzania Institute of Material. Science University of Connecticut Storrs USA School.of Engineering Brown University Providence USA

Nanocl.ster formation of a metal.ic pl.tinum (Pt) coating, on manganese oxide inorganic membranes impregnated with mul.iwal. carbon nanotubes (K-OMS-2/MWCNTs), appl.ed by reactive spray deposition technol.gy (RSDT) is discussed. RSDT appl.es thin fil.s of Pt nanocl.sters on the substrate;the thickness of the fil. can be easil. control.ed. The K-OMS-2/MWCNTs fibers were encl.sed by the thin fil. of Pt. X-ray diffraction (XRD), scanning el.ctron microscopy/X-ray energy dispersive spectroscopy (SEM/XEDS), focus ion beam/scanning el.ctron microscopy (FIB/SEM), transmission el.ctron microscopy (TEM), and X-ray 3D micro-tomography (MicroXCT) which have been used to characterize the resul.ant Pt/K-OMS-2/MWCNTs membrane. The non-destructive characterization technique (MicroXCT) resol.es the Pt l.yer on the upper l.yer of the composite membrane and al.o shows that the membrane is composed of sheets superimposed into stacks. The nanostructured coating on the composite membrane material.has been eval.ated for carbon monoxide (CO) oxidation. The functional.zed Pt/K-OMS-2/MWCNTs membranes show excel.ent conversion (100%) of CO to CO2 at a l.wer temperature 200℃ compared to the uncoated K-OMS-2/MWCNTs. Moreover, the Pt/K-OMS-2/MWCNTs membranes show outstanding stabil.ty, of more than 4 days, for CO oxidation at 200℃.

关键词： Manganese Oxide Membrane Pt Nanostructures Reactive Spray Deposition Technol.gy (RSDT) Fil. Deposition X-Ray Tomography