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National Science Review 2021年第5期8卷 57-66页

作者： Fangyuan Mao Cunyu Liu Morgan Hill Chase Andrew K.smith Jin Meng Key Laboratory of Evolutionary Systematics of Vertebrates Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of Sciences CAS Center for Excellence in Life and Paleoenvironment division of Paleontology American Museum of Natural History Beipiao Pterosaur Museum of China 5. Microscopy and Imaging Facility American Museum of Natural History Earth and Environmental Sciences Graduate CenterCity University of New York

We report a new Cretaceous multituberculate mammal with 3 d.a.ditory bones preserved. Along with other fossil and extant mammals, the unequivocal auditory bones display features potentially representing ancestral phenotypes of the mammalian middle ear. These phenotypes show that the ectotympanic and the malleus-incus complex changed notably during their retreating from the dentary at various evolutionary stages and suggest convergent evolution of some features to extant mammals. In contrast, the incudomalleolar joint was conservative in having a braced hinge configuration, which narrows the morphological gap between the quadroarticular jaw joint of non-mammalian cynodonts and the incudomalleolar articulations of extant mammals. The saddle-shaped.a.d.a.utting malleus-incus complexes in therians and monotremes, respectively, could have evolved from the braced hinge joint *** evolutionary changes recorded in the Mesozoic mammals are largely consistent with the middle ear morphogenesis during the ontogeny of extant mammals, supporting the relation between evolution and development.

关键词： Cretaceous Jehol Biota malleus-incus ectotympanic mammal evolution

NANO-ANd MICRO-TECHNOLOGIES FOR GAMETES,EMBRYOS,ANd EMBRYONIC STEM CELLS

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NANO-AND MICRO-TECHNOLOGIES FOR GAMETES,EMBRYOS,AND EMBRYONI...

Outcomes of Medicare beneficiaries hospitalised with transient ischaemic attack and stratification using the ABCd^(2) score

The 5th Annual Conference of the Asian Reproductive Biotechnology Society

作者： Gary d.smith departments of Ob/Gyn PhysiologyUrology director Reproductive Sciences Program University of Michigan Ann ArborMIUSA

＜正＞In vitro fertilization（IVF）remains one of the most exciting modem scientific developments and continues to have a tremendous impact on people’s *** its beginning,scientists have studied.a.d critically analyze...

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Stroke & Vascular Neurology 2021年第2期6卷 314-318页

作者： Shreyansh Shah Li Liang durgesh Bhandary Saga Johansson Eric E smith deepak L Bhatt Gregg C Fonarow Naeem d Khan Eric Peterson Janet Prvu Bettger department of Neurology Duke University School of MedicineDurhamNorth CarolinaUSA duke Clinical Research Institute DurhamNorth CarolinaUSA AstraZeneca UK Ltd CambridgeUK Hotchkiss Brain Institute and department of Clinical Neurosciences University of CalgaryCalgaryAlbertaCanada division of Cardiology Brigham and Women's HospitalBostonMassachusettsUSA division of Cardiology Ronald Reagan UCLA Medical CenterLos AngelesCaliforniaUSA

Background Long-term outcomes for Medicare beneficiaries hospitalised with transient ischaemic attack(TIA)and role of ABCd^(2) score in identifying high-risk individ.a.s are not *** We identified 40825 Medicare beneficiaries hospitalised from 2011 to 2014 for a TIA to a Get With The Guidelines(GWTG)-Stroke hospital and classified them using ABCd^(2)s of mortality and rehospitalisation(all-cause,ischaemic stroke,haemorrhagic stroke,myocard.a. infarction,and gastrointestinal and intracranial haemorrhage)for high-risk versus low-risk groups adjusted for patient and hospital *** Of the 40825 patients,35118(86%)were high risk(ABCd^(2)≥4)and 5707(14%)were low risk(ABCd^(2)=0-3).Overall rate of mortality during 1-year follow-up after hospital discharge for the index TIA was 11.7%,44.3% were rehospitalised for any reason and 3.6%were readmitted due to *** with ABCd^(2) score≥4 had higher mortality at 1 year than not(adjusted HR 1.18,95%CI 1.07 to 1.30).Adjusted risks for ischaemic stroke,all-cause readmission and mortality/all-cause readmission at 1 year were also significantly higher for patients with ABCd^(2) score≥4 vs *** contrast,haemorrhagic stroke,myocard.a. infarction,gastrointestinal bleeding and intracranial haemorrhage risk were not significantly different by ABCd^(2) *** This study validates the use of ABCd^(2) score for long-term risk assessment after TIA in patients aged 65 years and *** efforts for community-based follow-up care after TIA are needed for ongoing prevention in Medicare beneficiaries who were hospitalised for TIA.

关键词： admitted score prevention

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碳-60新材料及其纳米结构特点

科学通报 1992年第9期37卷 850-852页

作者：温树林刘冉 d.smith 中国科学院上海硅酸盐研究所上海200050 美国伊里诺大学材料研究实验室美国亚利桑那州立大学固体科学中心

不少科学家最近将他们的注意力转向碳-60。这一方面是由于碳-60在结构上意义极不寻常,它是金刚石和石墨以外的第三种碳的结晶形式;

关键词：碳-60 纳米结构晶体

Lattice Boltzmann Simulations of Two Linear Microswimmers Using the Immersed Boundary Method

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Communications in Computational Physics 2023年第1期33卷 310-329页

作者： d.Geyer S.Ziegler A.Sukhov M.Hubert A.-S.smith O.Aouane P.Malgaretti J.Harting Helmholtz Institute Erlangen-Nurnberg for Renewable Energy(IEK-11) Forschungszentrum JulichCauerstrase 191058 ErlangenGermany PULS Group Department of PhysicsInterdisciplinary Center for Nanostructured FilmsFriedrich-Alexander-Universitat Erlangen-NurnbergCauerstrase 391058 ErlangenGermany department of Chemical and Biological Engineering and department of Physics Friedrich-Alexander-Universitat Erlangen-N¨urnbergFurther Strase 24890429 NurnbergGermany

The performance of a single or the collection of microswimmers strongly depends on the hydrodynamic coupling among their constituents and *** present a numerical study for a single and.a.pair of microswimmers based on lattice Boltzmann method(LBM)*** numerical algorithm consists of two separable *** polynomials provide a discretization of the microswimmers and the lattice Boltzmann method captures the dynamics of the surrounding *** two components couple via an immersed boundary *** present data for a single swimmer system and our data also show the onset of collective effects and,in particular,an overall velocity increment of clusters of swimmers.

关键词： Immersed boundary method lattice Boltzmann method finite element method microswimmer collective motion

THE FEASIBILITY OF USING VERTICAL-LOOKING RAdAR TO MONITOR THE MIGRATION OF BROWN PLANTHOPPER ANd OTHER INSECT PESTS OF RICE IN CHINA

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Entomologia Sinica 2003年第1期10卷 1-19页

作者： Joe R.Riley A.d.smith d.R.Reynolds Plant and Invertebrate Ecology division Rothamsted ResearchHarpenden Hertfordshire AL5 2JQUKPlant and Invertebrate Ecology DivisionRothamsted ResearchHarpenden Hertfordshire AL5 2JQUKRadar Entomology Unit Plant Animal and Human Health Group Natural Resource s Institute University of Greenwich Central Avenue Chatham Kent ME4 4TB UK

The recent development of automatically operating, inexpensive vertical-looking radar (VLR) for entomological purposes has made it practical to carry out routine, automated monitoring of insect aerial migration throughout the year. In this paper we investigate whether such radars might have a role in monitoring and forecasting schemes designed to improve the management of the Brown Planthopper (BPH), Nilaparvata lugens, and of associated rice pest species in China. A survey of the literature revealed that these insects typically migrate at altitudes between 300 to 2 000 m above ground level, but calculations based on BPH radar scattering cross-sections indicated that the maximum altitude at which they individ.a.ly produce signals analysable by current VLRs is only～240 m. We also show that coverage over most of the flight altitudes of BPH could be achieved by building a VLR using a wavelength of 8.8 mm instead of the 3.2 cm of existing VLR, but that such a radar would be expensive to build.a.d to operate. We suggest that a more practical solution would be to use a 3.2 cm VLR as a monitor of the aerial movement of the larger species, from which the migration of rice pests in general might be inferred.

关键词： Radar migration flight brown planthopper rice pests.

Thinking inside the Box: Tissue Culture for Plant Propagation in a Key Ecological Species, <i>Andropogon gerardii</i>

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American Journal of Plant Sciences 2018年第10期9卷 1987-2003页

作者： Ava M. Hoffman Melinda d. smith department of Biology/Grad.a.e degree Program in Ecology Colorado State University Fort Collins USA

Intraspecific diversity has widespread effects on ecological communities and ecosystems. To elucidate the mechanisms underlying these effects, manipulative studies require a rigorous and efficient empirical approach. Yet, replicating sufficient numbers of genetically identical individ.a.s remains a challenge. As a result, we are limited in our understanding of the mechanisms underlying the ecological effects of intraspecific diversity. In contrast, large sample sizes are routinely produced in horticultural research using micropropagation, or tissue culture. In order to determine the potential usefulness of micropropagation technique for ecological studies, we investigated the efficiency and efficacy of micropropagation on the ecologically important non-model C4 grass species, Andropogon gerardii. Our preliminary results demonstrate that micropropagation is a rapid.a.d effective technique for producing large numbers of genetically identical clones at up to 100 times the rate of traditional propagation. Key intraspecific differences among clones of A. gerardii were also retained through the micropropagation process. Given that traditional techniques used to test the effects of intraspecific diversity manipulations are time-limiting (greenhouse propagation) or can be biologically misrepresentative (seeds) for some species, we suggest that micropropagation might be a powerful tool for ad.a.cing ecological genetics studies in many plant systems.

关键词： Intraspecific diversity Micropropagation Perennial Grass Ecology

High-Level Accumulation of Exogenous Small RNAs Not Affecting Endogenous Small RNA Biogenesis and Function in Plants

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Journal of Integrative Agriculture 2014年第5期13卷 1017-1023页

作者： SHEN Wan-xia Neil A smith ZHOU Chang-yong WANG Ming-bo College of Plant Protection Southwest University CSIRO Plant Industry National Citrus Engineering Research Center Citrus Research Institute Chinese Academy of Agricultural Sciences

RNA silencing is a fundamental plant defence and gene control mechanism in plants that are directed by 20-24 nucleotide （nt） small interfering RNA （siRNA） and microRNA （miRNA）. Infection of plants with viral pathogens or transformation of plants with RNA interference （RNAi） constructs is usually associated with high levels of exogenous siRNAs, but it is unclear if these siRNAs interfere with endogenous small RNA pathways and hence affect plant development. Here we provide evidence that viral satellite RNA （satRNA） infection does not affect siRNA and miRNA biogenesis or plant growth despite the extremely high level of satRNA-derived siRNAs. We generated transgenic Nicotiana benthamiana plants that no longer develop the specific yellowing symptoms generally associated with infection by Cucumber mosaic virus （CMV） Y-satellite RNA （Y-Sat）. We then used these plants to show that CMV Y-Sat infection did not cause any visible phenotypic changes in comparison to uninfected plants, despite the presence of high-level Y-Sat siRNAs. Furthermore, we showed that the accumulation of hairpin RNA （hpRNA）-derived siRNAs or miRNAs, and the level of siRNA-directed transgene silencing, are not significantly affected by CMV Y-Sat infection. Taken together, our results suggest that the high levels of exogenous siRNAs associated with viral infection or RNAi-inducing transgenes do not saturate the endogenous RNA silencing machineries and have no significant impact on normal plant development.

关键词： Nicotiana benthamiana transformation satellite RNA RNA silencing small RNA

Behavior of ZrO_2-C Refractories in Thin-strip Casting of Steel

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China's Refractories 2015年第1期24卷 1-6页

作者： Abhishek KUMAR Vivek THAPLIYAL Jeffrey d.smith Materials Science and Engineering department Missouri University of Science & Technology

Zirconia graphite refractory is used.a. a core-nozzle in the thin-strip casting of steel. Post-mortem analysis of used refractory was performed in an effort to establish the failure mechanism. Corrosion behavior was studied.a.ainst molten steel with Mn O- SiO 2based liquid inclusions. Corrosion of these materials involves dissolution and oxidation of graphite in the matrix followed by penetration of liquid slag leading to degradation of ZrO 2particles. Thermodynamic equilibrium calculations were performed to study this corrosion mechanism.

关键词： zirconia-graphite corrosion dissolution thermodynamic-modeling

Fibroblast growth factor receptor 3 effects on proliferation and telomerase activity in sheep growth plate chondrocytes

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Journal of Animal Science and Biotechnology 2013年第1期4卷 41-48页

作者： Logan B smith Janelle M Belanger Anita M Oberbauer department of Animal Science University of California

Background： Fibroblast growth factor receptor 3 （FGFR3） inhibits growth-plate chondrocyte proliferation and limits bone elongation. Gain-of-function FGFR3 mutations cause d.a.fism, reduced telomerase activity and shorter telomeres in growth plate chondroyctes suggesting that FGFR3 reduces proliferative capacity, inhibits telomerase, and enhances senescence. Thyroid hormone （1-3） plays a role in cellular maturation of growth plate chondrocytes and.a.known target of T3 is FGFR3. The present study addressed whether reduced FGFR3 expression enhanced telomerase activity, mRNA expression of telomerase reverse transcriptase （TERT） and RNA component of telomerase （TR）, and chondrocyte proliferation, and whether the stimulation of FGFR3 by T3 evoked the opposite response. Results： Sheep growth-plate proliferative zone chondrocytes were cultured.a.d transfected with siRNA to reduce FGFR3 expression; FGFR3 siRNA reduced chondrocyte FGFR3 mRNA and protein resulting in greater proliferation and increased TERT mRNA expression and telomerase activity （p 〈 0.0.5）. Chondrocytes treated with T3 significantly enhanced FGFR3 mRNA and protein expression and reduced telomerase activity （p 〈 0.05）; TERT and TR were not significantly reduced. The action of T3 at the growth plate may be partially med.a.ed through the FGFR3 pathway. Conclusions： The results suggest that FGFR3 inhibits chondrocyte proliferation and reducing telomerase activity indicating an important role for telomerase in capacity during bone elongation. by down-regulating TERT expression sustaining chondrocyte proliferative

关键词： Chondrocytes Growth-plate Telomerase Fibroblast growth factor receptor 3 Thyroid hormone Sheep