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Numerical simulation on AC loss in REBCO tapes carrying non-sinusoidal currents

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Superconductivity 2023年第4期8卷 18-25页

作者： Katsuya Uejima Yueming Sun Daisuke Miyagi jakub Glowacki nicholas j.Long Zhenan jiang Department of Electrical and Electronic Engineering Chiba UniversityChiba 263-8522Japan Paihau-Robinson Research Institute Victoria University of WellingtonWellington 6140New Zealand

AC loss is one of the greatest obstacles for high‐temperature superconducting(HTS)*** some HTS applications,coated conductors carry non‐sinusoidal ***,it is important to investigate the effect of various waveforms on AC loss in coated *** this work,transport AC loss in a 4 mm‐wide REBCO coated conductor carrying sinusoidal and non‐sinusoidal currents,is numerically *** current amplitudes,the frequency of the transport current,and n‐value are ***‐sinusoidal transport current waveforms studied include square,five types of trapezoidal,and triangular *** results show that,for a given current amplitude,AC loss for the square current waveform is the greatest,that for the triangular waveform is the *** sequence of AC loss in the conductor for different current waveforms coincides with the penetration depth,which implies the penetration depth determines the AC loss of the coated ***,the transport AC loss in the conductor was found to decrease with frequency as f2=n for non‐sinusoidal transport current.

关键词： REBCO coated conductors AC loss Non‐sinusoidal current

Analysis of Gene Expression Patterns during Seed Coat Development in Arabidopsis

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Molecular Plant 2011年第6期4卷 1074-1091页

作者： Gillian Dean YongGuo Cao DaoQuan Xiang nicholas j. Provart Larissa Ramsay Abdul Ahad Rick White Gopalan Selvaraj Raju Datla George Haughn Department of Botany University of British Columbia 6270 University Blvd Vancouver BC V6T 1Z4 Canada National Research Council of Canada Plant Biotechnology Institute 110 Gymnasium Place Saskatoon SK S7N owg Canada Department of Cell and Systems Biology/Centre for the Analysis of Genome Evolution and Function University of Toronto 25 Willcocks St Toronto ON M5S 3B2 Canada Department of Statistics University of British Columbia 6356 Agricultural Road Vancouver BC V6T 1Z2 Canada

The seed coat is important for embryo protection, seed hydration, and dispersal. Seed coat composition is also of interest to the agricultural sector, since it impacts the nutritional value for humans and livestock alike. Although some seed coat genes have been identified, the developmental pathways controlling seed coat development are not completely elucidated, and a global genetic program associated with seed coat development has not been reported. This study uses a combination of genetic and genomic approaches in Arabidopsis thaliana to begin to address these knowledge gaps. Seed coat development is a complex process whereby the integuments of the ovule differentiate into specialized cell types. In Arabidopsis, the outermost layer of cells secretes mucilage into the apoplast and develops a secondary cell wall known as a columella. The layer beneath the epidermis, the palisade, synthesizes a secondary cell wall on its inner tangential side. The innermost layer （the pigmented layer or endothelium） produces proanthocyanidins that condense into tannins and oxidize, giving a brown color to mature seeds. Genetic separation of these cell layers was achieved using the ap2-7 and tt16-1 mutants, where the epidermis/palisade and the endothelium do not develop respectively. This genetic ablation was exploited to examine the developmental programs of these cell types by isolating and collecting seed coats at key tran- sitions during development and performing global gene expression analysis. The data indicate that the developmental programs of the epidermis and the pigmented layer proceed relatively independently. Global expression datasets that can be used for identification of new gene candidates for seed coat development were generated. These dataset provide a comprehensive expression profile for developing seed coats in Arabidopsis, and should provide a useful resource and reference for other seed systems.

关键词： Seed coat microarray APETALA2 TRANSPARENT TESTA16 mucilage pectin secondary cell wall pigmentedlayer proanthocyanidin.

Scalable arrays of chemical vapor sensors based on DNA-decorated graphene

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Nano Research 2014年第1期7卷 95-103页

作者： nicholas j. Kybert Gang Hee Han Mitchell B. Lerner Eric N. Dattoli Ali Esfandiar A. T. Charlie johnson Department of Physics and Astronomy University of Pennsylvania Philadelphia PA 19104 USA SPAWAR Systems Center Pacific San Diego CA 92152 USA

Arrays of chemical vapor sensors based on graphene field effect transistors functionalized with single-stranded DNA have been demonstrated. Standard photolithographic processing was adapted for use on large-area graphene by including a metal protection layer, which protected the graphene from contamination and enabled fabrication of high quality field-effect transistors （GFETs）. Processed graphene devices had hole mobilities of 1,640 ± 250 cm2.V-1.s-1 and Dirac voltages of 15 ± 10 V under ambient conditions. Atomic force microscopy was used to verify that the graphene surface remained uncontaminated and therefore suitable for controlled chemical functionalization. Single-stranded DNA was chosen as the functionalization layer due to its affinity to a wide range of target molecules and π-π stacking interaction with graphene, which led to minimal degradation of device characteristics. The resulting sensor arrays showed analyte- and DNA sequence-dependent responses down to parts-per-billion concentrations. DNA/GFET sensors were able to differentiate among chemically similar analytes, including a series of carboxylic acids, and structural isomers of carboxylic acids and pinene. Evidence for the important role of electrostatic chemical gating was provided by the observation of understandable differences in the sensor response to two compounds that differed only by the replacement of a （deprotonating） hydroxyl group by a neutral methyl group. Finally, target analytes were detected without loss of sensitivity in a large background of a chemically similar, volatile compound. These results motivate further development of the DNA/graphene sensor family for use in an electronic olfaction system.

关键词： graphene vapor sensor DNA photolithography chemical gating

Influences and drivers of woody debris movement in urban watercourses

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Science China(Technological Sciences) 2014年第8期57卷 1512-1521页

作者： ALLEN Deonie ARTHUR Scott HAYNES Heather WALLIS Stephen G WALLERSTEIN nicholas Institute for Infrastructure and Environment Heriot-Watt University

It is recognised that the blockage of culverts by woody debris can result in an increased risk of infrastructure damage and *** date,debris transport analysis has focused on regional fluvial systems and large woody debris,both in flume and field *** the social and economic risk associated with urban flooding,and as urban drainage design shifts away from subsurface piped network reliance,there is an increasing need to understand debris movement in urban *** prediction of urban watercourse small woody debris(SWD)movement,both quantity and risk,has undergone only limited analysis predominantly due to lack of field *** paper describes the development of a methodology to enable the collection of accurate and meaningful SWD residency and transportation data from *** presented research examines the limitations and effective function of PIT tag technology to collect SWD transport data in the field appropriate for risk and prediction *** integrated transponder(PIT)technology provides a method to collect debris transport data within the urban *** this study,the tags are installed within small woody debris and released at known locations into a small urban natural watercourse enabling monitoring of movement and travel *** velocity and detention are collated with solute time of travel,watercourse and point flow characteristics to identify the relationships between these key *** work presented tests three hypotheses:firstly,that the potential for unobstructed or un-detained SWD movement increases with flow velocity and water ***,that SWD travel distance,and the resistance forces along this travel path,influence SWD transport ***,the relationship between SWD and channel dimensions is examined with the aim of advancing representative debris transport prediction modelling.

关键词： woody debris transport prediction urban flood risk blockage solute dye tracing

Underwater acoustic metamaterials

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National Science Review 2023年第6期10卷 258-280页

作者： Erqian Dong Peizheng Cao jinhu Zhang Sai Zhang nicholas X.Fang Yu Zhang Key Laboratory of Underwater Acoustic Communication and Marine Information Technology of the Ministry of Education College of Ocean and Earth Sciences Xiamen University State Key Laboratory of Marine Environmental Science Xiamen University School of Physics and Electronic Engineering Jiangsu University Department of Mechanical Engineering Massachusetts Institute of Technology

Acoustic metamaterials have been widely investigated over the past few decades and have realized acoustic parameters that are not achievable using conventional *** demonstrating that locally resonant acoustic metamaterials are capable of acting as subwavelength unit cells,researchers have evaluated the possibility of breaking the classical limitations of the material mass density and bulk *** with theoretical analysis,additive manufacturing and engineering applications,acoustic metamaterials have demonstrated extraordinary capabilities,including negative refraction,cloaking,beam formation and super-resolution *** to the complexity of impedance boundaries and mode transitions,there are still challenges in freely manipulating acoustic propagation in an underwater *** review summarizes the developments in underwater acoustic metamaterials over the past 20 years,which include underwater acoustic invisibility cloaking,underwater beam formation,underwater metasurfaces and phase engineering,underwater topological acoustics and underwater acoustic metamaterial *** the evolution of underwater metamaterials and the timeline of scientific advances,underwater acoustic metamaterials have demonstrated exciting applications in underwater resource development,target recognition,imaging,noise reduction,navigation and communication.

关键词： underwater acoustic metamaterials invisibility cloaking beam formation topological acoustics metasurfaces absorbers

Two-Layer High-Throughput:Effective Mass Calculations Including Warping

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Engineering 2022年第3期8卷 74-80页

作者： Andrew Supka nicholas A.Mecholsky Marco Buongiorno Nardelli Stefano Curtarolo Marco Fornari Department of Physics&Science of Advanced Materials Program Central Michigan UniversityMount PleasantMI 48859USA Department of Physics&Vitreous State Laboratory The Catholic University of AmericaWashingtonDC 20064USA Department of Physics&Department of Chemistry University of North TexasDentonTX 76203USA Center for Autonomous Materials Design Duke UniversityDurhamNC 27708USA Department of Mechanical Engineering and Materials Science Duke UniversityDurhamNC 27708USA

In this paper,we perform two-layer high-throughput *** the first layer,which involves changing the crystal structure and/or chemical composition,we analyze selected Ⅲ-Ⅴ semiconductors,filled and unfilled skutterudites,as well as rock salt and layered *** second layer searches the full Brillouin zone(BZ)for critical points within 1.5 eV(1 eV=1.602176×10^(-19)j)of the Fermi level and characterizes those points by computing the effective *** introduce several methods to compute the effective masses from first principles and compare them to each *** approach also includes the calculation of the density-of-states effective masses for warped critical points,where traditional approaches fail to give consistent results due to an underlying non-analytic behavior of the critical *** demonstrate the need to consider the band structure in its full complexity and the value of complementary approaches to compute the effective *** also provide computational evidence that warping occurs only in the presence of degeneracies.

关键词： High-throughput Electronic structure Band warping Effective mass

新版国际植物命名法规(维也纳法规)中的主要变化

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植物分类学报 2007年第2期45卷 251-255页

作者：张丽兵杨亲二 nicholas j.TURLAND john MCNEILL Missouri Botanical Garden 中国科学院植物研究所系统与进化植物学国家重点实验室 Missouri Botanical Garden Saint LouisMissouri 63166U.S.A Royal Ontario Museum Torontoand Royal Botanic Garden Edinburgh20A Inverleith RowEdinburghEH3 5LRScotlandU.K.

出版于2006年9月的最新版的《国际植物命名法规》,即维也纳法规(Vienna Code),取代了圣路易斯法规(Saint Louis Code)而成为管理植物学(包括藻类学和真菌学)科学命名的唯一有效法规。本文报道了维也纳法规和圣路易斯法规之间的主要区别... 详细信息

出版于2006年9月的最新版的《国际植物命名法规》,即维也纳法规(Vienna Code),取代了圣路易斯法规(Saint Louis Code)而成为管理植物学(包括藻类学和真菌学)科学命名的唯一有效法规。本文报道了维也纳法规和圣路易斯法规之间的主要区别。这些区别包括两版法规在起始日期、有效发表、合格发表、化石植物、多型真菌、拼写和附录诸方面的不同。

关键词：命名法维也纳法规主要变化

The Immune System,Cytokines,and Biomarkers in Autism Spectrum Disorder

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Neuroscience Bulletin 2017年第2期33卷 194-204页

作者： Anne Masi nicholas Glozier Russell Dale Adam j.Guastella Autism Clinic for Translational Research Brain and Mind CentreCentral Clinical SchoolSydney Medical SchoolUniversity of SydneySydneyNew South Wales 2050Australia Childrens Hospital at Westmead Clinical School Universityof SydneySydneyNew South Wales 2145Australia

Autism Spectrum Disorder（ASD） is a pervasive neurodevelopmental condition characterized by variable impairments in communication and social interaction as well as restricted interests and repetitive *** of presentation is a hallmark. Investigations of immune system problems in ASD, including aberrations in cytokine pro？les and signaling, have been increasing in recent times and are the subject of ongoing interest. With the aim of establishing whether cytokines have utility as potential biomarkers that may de？ne a subgroup of ASD,or function as an objective measure of response to treatment, this review summarizes the role of the immune system, discusses the relationship between the immune system, the brain, and behavior, and presents previouslyidenti？ed immune system abnormalities in ASD, speci？-cally addressing the role of cytokines in these *** roles and identi？cation of biomarkers are also addressed, particularly with respect to cytokine pro？les in ASD.

关键词： Autism Spectrum Disorder Cytokine Immune system

Effect of vaccination,border testing,and quarantine requirements on the risk of COVID-19 in New Zealand:A modelling study

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Infectious Disease Modelling 2022年第1期7卷 184-198页

作者： nicholas Steyn Audrey Lustig Shaun C.Hendy Rachelle N.Binny Michael j.Plank Department of Physics University of AucklandNew Zealand School of Mathematics and Statistics University of CanterburyNew Zealand Te Punaha Matatini Centre of Research Excellence in Complex SystemsNew Zealand Manaaki Whenua LincolnNew Zealand

We couple a simple model of quarantine and testing strategies for international travellers with a model for transmission of SARS-CoV-2 in a partly vaccinated *** use this model to estimate the risk of an infectious traveller causing a community outbreak under various border control strategies and different levels of vaccine coverage in the *** are calculated from N¼100,000 independent realisations of the stochastic *** find that strategies that rely on home isolation are significantly higher risk than the current mandatory 14-day stay in government-managed ***,combinations of testing and home isolation can still reduce the risk of a community outbreak to around one outbreak per 100 infected *** also find that,under some circumstances,using daily lateral flow tests or a combination of lateral flow tests and polymerase chain reaction(PCR)tests can reduce risk to a comparable or lower level than using PCR tests *** with controls on the number of travellers from countries with high prevalence of COVID-19,our results allow different options for managing the risk of COVID-19 at the border to be *** can be used to inform strategies for relaxing border controls in a phased way,while limiting the risk of community outbreaks as vaccine coverage increases.

关键词： vaccine testing border