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Maintenance of Species Differences in Closely Related Tetraploid Parasitic Euphrasia (Orobanchaceae) on an Isolated Island

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Plant Communications 2020年第6期1卷 85-99页

作者： Hannes Becher Max R.Brown Gavin Powell chris Metherell Nick j.Riddifordand Alex D.Twyford University of Edinburgh School of Biological SciencesInstitute of Evolutionary BiologyCharlotte Auerbach RoadEdinburgh EH93FLUK Royal Botanic Garden Edinburgh 20A Inverleith RowEdinburgh EH35LRUK Botanical Society of Britain and Ireland 4 High Firs CrescentHarpendenHertfordshire AL51NAUK Schoolton Fair IsleShetland ZE29JUUK

Polyploidy is pervasive in angiosperm evolution and plays important roles in adaptation and ***,polyploid groups are understudied due to complex sequence homology,challenging genome assembly,and taxonomic ***,we study adaptive divergence in taxonomically complex eyebrights(Euphrasia),where recent divergence,phenotypic plasticity,and hybridization blur species *** focus on three closely related tetraploid species with contrasting ecological preferences that are sympatric on Fair Isle,a small isolated island in the British *** a common garden experiment,we show a genetic component to the morphological differences present between these *** wholegenome sequencing and a novel k-mer approach we call“Tetmer”,we demonstrate that the species are of allopolyploid origin,with a sub-genome divergence of approximately 5%.Using2 million SNPs,we show sub-genome homology across species,with a very low sequence divergence characteristic of recent *** genetic variation is broadly structured by species,with clear divergence of Fair Isle heathland Euphrasia micrantha,while grassland Euphrasia arctica and coastal Euphrasia foulaensis are more closely ***,we show that tetraploid Euphrasia is a system of allopolyploids of postglacial species divergence,where adaptation to novel environments may be conferred by old variants rearranged into new genetic lineages.

关键词： incipient speciation k-mer spectrum allopolyploidy tetraploid divergence with gene flow taxonomic complexity

Effect of B vitamin supplementation on plasma homocysteine levels in celiac disease

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World journal of Gastroenterology 2009年第8期15卷 955-960页

作者： Muhammed Hadithi chris jj Mulder Frank Stam joshan Azizi j Bart A Crusius Amado Salvador Pea Coen DA Stehouwer Yvo M Smulders Department of Gastroenterology VUmc University Medical Center Amsterdam PO Box 7057 Amsterdam 1007 MB The Netherlands Department of Internal Medicine VUmc University Medical Center Amsterdam PO Box 7057 Amsterdam 1007 MB The Netherlands Laboratory of Immunogenetics Department of Pathology VUmc University Medical Center Amsterdam PO Box 7057 Amsterdam 1007 MB The Netherlands Department of Internal Medicine Academic Hospital Maastricht P. Debyelaan 25 6229 HX Maastricht The Netherlands

AIM: To investigate the effect of vitamin supplements on homocysteine levels in patients with celiac disease. METHODS: Vitamin B6, folate, vitamin B12, and fasting plasma homocysteine levels were measured in 51 consecutive adults with celiac disease [median (range) age 56 (18-63) years; 40% men, 26 (51%) had villous atrophy, and 25 (49%) used B-vitamin supplements] and 50 healthy control individuals matched for age and sex. Finally, the C677T polymorphism of 5,10-methylene tetrahydrofolate reductase (MTHFR) was evaluated in 46 patients with celiac disease and all control individuals. RESULTS: Patients with celiac disease and using vitamin supplements had higher serum vitamin B6 (P = 0.003),folate (P < 0.001), and vitamin B12 (P = 0.012) levels than patients who did not or healthy controls (P = 0.035, P < 0.001, P = 0.007, for vitamin B6, folate, and vitamin B12, respectively). Lower plasma homocysteine levels were found in patients using vitamin supplements than in patients who did not (P = 0.001) or healthy controls (P = 0.003). However, vitamin B6 and folate, not vitamin B12, were significantly and independently associated with homocysteine levels. Twenty-four (48%) of 50 controls and 23 (50%) of 46 patients with celiac disease carried the MTHFR thermolabile variant T-allele (P = 0.89). CONCLUSION: Homocysteine levels are dependent on Marsh classification and the regular use of B-vitamin supplements is effective in reduction of homocysteine levels in patients with celiac disease and should be considered in disease management.

关键词： Celiac disease Homocysteine Vitamin supplements

Delayed juvenile behavioral development and prolonged dependence are adaptations to desert life in the grey falcon

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Current Zoology 2022年第6期68卷 679-687页

作者： jonny SCHOENjAHN chris R.PAVEY Gimme H.WALTER School of Biological Sciences The University of QueenslandBrisbaneQLD 4072Australia CSIRO Land and Water DarwinNT 0822Australia

Rapid learning in the young of most endothermic animals can be expected to be favored by natural selection because early independence reduces the period of *** of comparatively slow juvenile development continue,therefore,to attract scientific *** most species of birds,including raptors,the young depend on their parents for some time after fledging for the provisioning of food and for protection while they learn to become nutritionally and otherwise *** raptors,post-fledging dependence periods that exceed 6 months are exclusive to the largest species and these have reproductive cycles that exceed 12 *** contrast,young of the medium-sized grey falcon Falco hypoleucos have been reported in close company with their parents up to 12 months after fledging,that is,at a time when the adults are expected to breed *** investigated the occurrence and characteristics of prolonged adult–juvenile association relative to other falcons and similar-sized *** found that the behavioral development of grey falcon young is extremely delayed,and that they even depend nutritionally on their parents for up to 12 months after *** suggest that these 2 distinctive features are,ultimately,adaptations of the grey falcon to its extreme environment,Australia’s arid and semi-arid zone,one of the hottest environments in the world.

关键词： arid environment behavioral adaptation bird of prey post-fledging period

Using a systems modeling approach to improve soil management and soil quality

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Frontiers of Agricultural Science and Engineering 2020年第3期7卷 289-295页

作者： Enli WANG Di HE Zhigan ZHAO chris j.SMITH Ben C.T.MACDONALD CSIRO Agriculture and Food CanberraACT 2601Australia

Soils provide the structural support, water andnutrients for plants in nature and are considered to be thefoundation of agriculture production. Improving soilquality and soil health has been advocated as the goal ofsoil management toward sustainable agricultural intensifi-cation. There have been renewed efforts to define andquantify soil quality and soil health but establishing aconsensus on the key indicators remains difficult. It isargued that such difficulties are due to the former ways ofthinking in soil management which largely focus on soilproperties alone. A systems approach that treats soils as akey component of agricultural production systems ispromoted. It is argued that soil quality must be quantifiedin terms of crop productivity and impacts on ecosystemsservices that are also strongly driven by climate andmanagement interventions. A systems modeling approachcaptures the interactions among climate, soil, crops andmanagement, and their impacts on system performance,thus helping to quantify the value and quality of ***, three examples are presented to demonstrate this. Inthis systems context, soil management must be an integralpart of systems management practices that also includemanaging the crops and cropping systems under specificclimatic conditions, with cognizance of future climatechange.

关键词： APSIM available water capacity nitrogen management soil functional properties soil health soil-plant modeling

e-VLBI observations of GRB 080409 afterglow with an Australasian radio telescope network

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Research in Astronomy and Astrophysics 2016年第11期16卷 1-6页

作者： Aquib Moin Philip G. Edwards Steven j. Tingay chris j. Phillips Anastasios K. Tzioumis Shaun W. Amy Tao An Mamoru Sekido Zhong-Xiang Wang Physics Department United Arab Emirates University RO. Box 15551 A1-Ain United Arab Emirates Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China International Centre for Radio Astronomy Research Curtin University Bentley WA Australia CSIRO Astronomy and Space Science P.O. Box 76 Epping NSW 2121 Australia Kashima Space Research Center National Institute of Information and Communications Technology (NICT) 893-1 Hirai Kashima 314-0014 Ibaraki Japan Key Laboratory of Radio Astronomy Chinese Academy of Sciences Nanjing 210008 China Osservatorio di Radio Astronomia Istituto Nazionale di Astrofisica Italy

Transcontinental e-VLBI observations were conducted in june 2008 with telescopes in Australia, China and japan. Detections were made of the radio-loud quasar PKS B0727-115, which shows superlu- minal motion, and the intra-day variable quasar PKS B0524＋034. The latter source was used as a phase reference calibrator for observations at the position of the gamma-ray burst GRB 080409, for which an upper limit to the radio emission is set. Australia Telescope Compact Array data were also used to derive a limit on the radio flux density of the GRB afterglow. These observations demonstrate the capability to form a large Australasian radio telescope network for e-VLBI, with data transported and processed in realtime over high capacity networks. This campaign represents the first step towards more regular e-VLBI observations in this region.

关键词： techniques: interferometric -- galaxies: active -- gamma rays: bursts

面理弯切轴测量技术在造山带研究中的应用--以美国阿肯色河地区为例

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岩石学报 2012年第6期28卷 1937-1948页

作者：曹汇 chris FLETCHER 大陆构造与动力学国家重点实验室中国地质科学院地质研究所北京100037 澳大利亚詹姆斯库克大学地球科学学院澳大利亚汤斯维尔Qld 4811

基于变形分解理论提出的面理弯切轴测量技术,通过对变斑晶中多期面理的测定分析,为厘定造山运动中的变形过程提供了新的精确定量研究手段。面理弯切轴数据已经被用于解决地质领域多种问题,例如:研究造山运动过程中变形变质历史以及在区... 详细信息

基于变形分解理论提出的面理弯切轴测量技术,通过对变斑晶中多期面理的测定分析,为厘定造山运动中的变形过程提供了新的精确定量研究手段。面理弯切轴数据已经被用于解决地质领域多种问题,例如:研究造山运动过程中变形变质历史以及在区域和造山带尺度对比多期变质作用;论证变斑晶生长过程是否发生旋转;变斑晶成核生长与区域变形过程之间的关系;重建板块运动历史过程;约束不同地质事件的发生时限;划分复杂变形分解类型以及岩浆侵位机制及时限研究。本文主要介绍面理弯切轴测量方法的原理、具体测定方法、研究意义及应用范围,并以美国阿肯色地区为例,详细介绍了面理弯切轴测量技术在造山运动过程区域变形历史重建中的应用。

关键词：造山运动过程面理弯切轴变斑晶变形分解作用

Maturity-associated considerations for training load,injury risk,and physical performance in youth soccer:One size does not fit all

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journal of Sport and Health Science 2021年第4期10卷 403-412页

作者： chris Towlson jamie Salter jack D.Ade Kevin Enright Liam D.Harper Richard M.Page james j.Malone Department of Sport Health and Exercise ScienceUniversity of HullHull HU67RXUK School of Sport York St John UniversityYork YO317EXUK Liverpool FC Academy Liverpool Football ClubLiverpool L337EDUK Research Institute for Sport and Exercise Sciences L3Liverpool John Moores UniversityLiverpool L33AUK Human and Health Sciences University of HuddersfieldHuddersfield HD13DHUK Department of Sport and Physical Activity Edge Hill UniversityOrmskirk L394QPUK School of Health Sciences Liverpool Hope UniversityLiverpool L169JDUK

Biological maturation can be defined as the timing and tempo of progress to achieving a mature *** estimation of age of peak height velocity(PHV)or percentage of final estimated adult stature attainment(%EASA)is typically used to inform the training process in young *** youth soccer,maturity-related changes in anthropometric and physical fitness characteristics are diverse among individuals,particularly around *** this time,players are also at an increased risk of sustaining an overuse or growth-related *** a result,the implementation of training interventions can be *** purpose of this review was to(1)highlight and discuss many of the methods that can be used to estimate maturation in the applied setting and(2)discuss the implications of manipulating training load around PHV on physical development and injury *** have provided key stakeholders with a practical online tool for estimating player maturation status(Supplementary Maturity Estimation Tools).Whilst estimating maturity using predictive equations is useful in guiding the training process,practitioners should be aware of its *** increase the accuracy and usefulness of data,it is also vital that sports scientists implement reliable testing protocols at predetermined time-points.

关键词： Growth Injury Maturation Soccer Training

Preliminary Mo isotope data of Phanerozoic clastic sediments from the northern margin of the Yangtze block and its implication for paleoenvironmental conditions

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Chinese Science Bulletin 2009年第5期54卷 822-829页

作者： ZHOU Lian GAO Shan chris Hawkesworth COREY Archer XIE ShuCheng State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Wuhan 430074 China Department of Earth Sciences University of Bristol Bristol BS8 1R J U.K.

Mo isotopes along with Nd isotopes and other geochemical characteristics of the Phanerozoic clastic sediments from the northern margin of the Yangtze block were analyzed by MC-ICP-MS and some other techniques, spanning the period from Cambrian to jurassic. The δ 98Mo values and εNd(t ) in these sedimets were observed to exhibit a large range of variation (?0.65‰―+1.87‰, ?1.46―?10.90, respec-tively). Specifically, the sample from Late Permian Maokou Formation has relatively positive values in both δ 98Mo and εNd(t ) (+0.97‰, ?1.46, respectively). These elevated values are proposed to relate to the input of a large quantity of H2S and HS- into the contemporaneous seawater by the volcanic eruption of the Emeishan mantle plume. Introduction of these sulfide gases would cause MoO42? to be transferred into MoS24?, favoring the preferential deposition of the heavy Mo isotope as MoS24? and thus leaving a positive Mo isotope value. The sample from Late Permian Changxing Formation has a significantly elevated δ 98Mo value of +1.87‰, in association with the relatively negative εNd(t ) (?10.90) and remain the relatively higher content of both TOC and total sulfur (TS) (1.52%, 2.02%, respectively). This infers the presence of the enhanced primary productivity and high organic burial during the Changxing pe-riod. The production of a huge quantity of HS? and H2S by the sulfate-reducing reaction led to the ex-istence of the elevated seawater δ 98Mo values during the Changxing period. The preliminary Phanero-zoic data reported here allow us to propose that the Mo isotope signature preserved in reductive sediments is related to the regional tectonic settings and the associated environmental conditions, and thus the measurement of δ 98Mo promotes our understanding on the evolution of the paleoenviron-mental event in the Earth history.

关键词：钼同位素古环境显生宙长江

Study of disorder in pulsed laser deposited double perovskite oxides by first-principle structure prediction

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npj Computational Materials 2021年第1期7卷 826-833页

作者： Edoardo Fertitta Sujit Das Debalina Banerjee Farbod Ebrahimi Clément Barraud Kai Du He Tian chris j.Pickard Cedric Weber Ramamoorthy Ramesh Peter Littlewood David Dubbink Happy Electron Ltd. LondonUnited Kingdom Department of Materials Science and Engineering University of CaliforniaBerkeleyCAUSA Department of Physics King’s College LondonLondonUnited Kingdom Laboratoire Matériaux et Phénomènes Quantiques UMR 7162Universitéde ParisCNRSParisFrance Center of Electron Microscopy School of Materials Science and EngineeringZhejiang UniversityHangzhouChina Department of Materials Science and Metallurgy CambridgeUnited Kingdom Advanced Institute for Materials Research Tohoku UniversitySendaiJapan Department of Physics James Franck InstituteUniversity of ChicagoChicagoILUSA

Double perovskite oxides,with generalized formula A_(2)BB'O_(6),attract wide interest due to their multiferroic and charge transfer *** offer a wide range of potential applications such as spintronics and electrically tunable ***,great practical limitations are encountered,since a spontaneous order of the B-site cations is notoriously hard to *** this joint experimental-theoretical work,we focused on the characterization of double perovskites La2TiFeO6 and La_(2)VCuO_(6) films grown by pulsed laser deposition and interpretation of the observed B-site disorder and partial charge transfer between the B-site ions.A random structure sampling method was used to show that several phases compete due to their corresponding configurational *** order to capture a representative picture of the most relevant competing microstates in realistic experimental conditions,this search included the potential formation of non-stoichiometric phases as well,which could also be directly related to the observed partial charge *** optimized the information encapsulated in the potential energy landscape,captured via structure sampling,by evaluating both enthalpic and entropic *** terms were employed as a metric for the competition of different *** approach,applied herein specifically to La_(2)TiFeO_(6),highlights the presence of highly entropic phases above the ground state which can explain the disorder observed frequently in the broader class of double perovskite oxides.

关键词： laser double structure