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multiple ecological strategies explain the distribution of exotic and native C_(4) grasses in heterogeneous early successional sites in Hawai’i

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Journal of Plant Ecology 2017年第3期10卷 426-439页

作者： Rafael de Oliveira Xavier Carla m.d’Antonio Ecology and Conservation Lab Department of HydrobiologyFederal University of São CarlosWashington Luís Highwaykm 235São CarlosSão Paulo 13565-905Brazil Environmental Studies Program 4312-L Bren University of CaliforniaSanta BarbaraCA 93106USA

Aims Biotic homogenization results in novel communities contain-ing multiple exotic *** attributes that contribute to the dominance of invaders and increase invasibility of communities have been identified,but rarely have factors governing the domi-nance of co-occurring invaders been *** we assess the presence and performance of five exotic and one native C_(4) grass species across local(microsite)and more broad-scale variation in fire history,soil age,altitude and *** ask whether species show preferences for the same conditions,whether all are constrained by poor soil development,and how their performance changes when alone versus *** addition to providing information useful to managers who want to control some of these species,such information can help to predict how distributions might change with climate change methods We measured percent cover and plant height of each grass species in 64 plots in each of 15 sites,located in young volcanic substrates across environmental gradients in Hawai’i Volcanoes National Park,Hawai’i,*** varied in fire history and soil age,across altitu-dinal and precipitation *** estimated microsite heteroge-neity by measuring rock cover and soil depth,where each species was present and in plots as a *** analyzed effects of pos-sible controlling variables using chi-square tests and Generalized Additive mixed *** Findings Two species(Schizachyrium condensatum and Hyparrhenia rufa)were absent in shallow soil,restricted to more mesic sites and showed increasing performance with soil *** contrast,two other species(Andropogon virginicus and melinis repens)tended to occur in shal-low soil with high rock cover across a wide range of *** addi-tional species(melinis minutiflora)was weakly affected by soil depth and was the dominant at higher elevation(more mesic)and on burned sites,especially in old *** species was largely absent from lower elevation si

关键词： elevation gradient fire invasive species melinis minutiflora soil depth

Fetkin-hydro,a new thermo-hydrological algorithm for low-temperature thermochronological m.deling

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Geoscience Frontiers 2021年第3期12卷 186-200页

作者： Francisco Sánchez Andres Barrea Federico m.dávila Andres mora Centro de Investigaciones en Ciencias de la Tierra(CICTERRA) CONICET-UNCFCEFyNCiudad UniversitariaAv.Vélez Sarsfield 16115000 CórdobaArgentina Facultad de matemática AstronomíaFísica y Computación(FAMAF)Ciudad UniversitariaAv.Medida Allende 21445000 CórdobaArgentina Ecopetrol BotafogoRio de JaneiroBrazil

despite two decades of major advances in the field of thermochronological m.deling,state-of-the-art numerical implementations still rely mostly on burial and exhumation processes to explain radiometric *** though such an approach has proved valuable,failing to account for other first-order geological variables has led to misinterpretations and therefore,calls for a *** this study a new version of the Fetkin(finite element temperature kinematics,Ecopetrol)program is *** new algorithm couples time-dependent hydrological and thermal calculations,thus rendering thermochronological ages that,instead of being solely dependent on the kinematical evolution of a system,conditioning by the fluid flow is also *** contrast with previous thermochronological m.dels,this work considers the influence of effective stress on rock properties(porosity and permeability)and therefore,in thermal *** analyses addressing relevant geological questions show not only the versatility of the code but also,new perspectives on forward low-temperature thermochronological *** circulation through pure-sandstone settings produce colder thermal architectures than those obtained in impermeable *** in cooling ages from m.dels with and without fluid circulation are up to 5 myr.A 4-fold variation in thrusting rates(0.5 km/myr to 2 km/myr)produces a 15-myr difference in cooling ages in m.dels with fluid flow,which contrasts to much lower differences,only 2 myr,in domains without(or minimal)fluid circulation.2d thermal solutions in fold-bend-fold thrust belts composed of sandstones remain static despite substantial relief development by kinematic folding.A case-study from Western Argentina,in the Andean Precordillera,confirms the plausibility of the numerical algorithm here posed and raises new questions on the first-order thermal controls in settings under deformation.

关键词： Thermochronology Hydrogeology Fluid flow Numerical m.deling

GENERALIZATION OF STEINER FORmULAFOR THE HOmOTHETIC mOTIONS ONTHE PLANAR KINEmATICS

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Applied mathematics and mechanics(English Edition) 2003年第8期24卷 945-949页

作者： N.Kuruo(g|ˇ)lu m.düldül A.Tutar department of mathematics Science and Arts Faculty Ondokuz Mayis UniversityKurupelit 55139 Samsun TurkeyDepartment of Mathematics Science and Arts Faculty Ondokuz Mayis UniversityKurupelit 55139 Samsun TurkeyDepartment of Mathematics Science and Arts Faculty Ondokuz Mayis UniversityKurupelit 55139 Samsun Turkey

The Steiner formula and the mixture area formula given by m(U|¨)ller were expressed under the one-parameter closed planar homothetic motions in the complex sense . Also, using the generalization of Steiner formula, the result of Holditch theorem for homothetic motions is got. In the case of the homothetic scale h≡1 the results given by m(U|¨)ller are obtained as a special case.

关键词： homothetic motion Steiner formula Holditch theorem

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Food Bioscience 2022年第6期50卷 1450-1467页

作者： Yuxin Qin Nenad Naumovski Chaminda Senaka Ranadheera Nathan m.d'Cunha School of Agriculture and Food Faculty of Veterinary and Agricultural ScienceThe University of MelbourneParkvilleVictoria3010Australia discipline of Nutrition and dietetics School of Rehabilitation and Exercise SciencesFaculty of HealthUniversity of CanberraBruceACT2601Australia Functional Foods and Nutrition Research (FFNR) Laboratory University of CanberraNgunnawal CountryACT2617Australia department of Nutrition and dietetics School of Health Science and EducationHarokopio University17671AthensGreece

Sweet potato (Ipomoea batatas ) thrives in a wide range of climates and is high in fibre, vitamins and minerals. There is increasing evidence that sweet potato consumption can positively affect human health. This systematic review aim.d to summarise nutritional-related health outcomes of sweet potato intake among healthy people and people with chronic diseases by reviewing human intervention trials. A total of 22 articles met the inclusion criteria, which examined the effects of sweet potato on vitamin A intakes and status (n = 8), glycemic markers and anthropometric parameters (n = 6), hepatic biomarkers (n = 3) and blood pressure (n = 1), iron absorption (n = 1), constipation (n = 1), nitrogen balance (n = 1), and sex hormones (n = 1). In the included studies, sweet potato consumption appears to improve vitamin A status, blood glucose levels, blood pressure, iron absorption, constipation, liver function and nitrogen balance. However, the evidence base is limited and future research in long-term, well-designed, randomised controlled trials are needed to establish cause-and-effect relationships with these health effects of sweet potato consumption. The functional properties of the bioactive compounds in sweet potatoes require further investigation to establish their ability to manage chronic disease when consum.d in high amounts.

关键词： Sweet potato Ipomoea batatas Vitamin A Blood glucose Blood pressure Systematic review

Cyanide-bridged single molecule magnet based on a manganese(Ⅲ) complex with TTF-fused Schiff base ligand

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Science China Chemistry 2015年第4期58卷 650-657页

作者： Long Cui Feifei Zhu Chanel F.Leong Jing Ru Feng Gao deanna m.d’Alessandro Jinglin Zuo State Key Laboratory of Coordination Chemistry School of Chemistry and Chemical Engineering Nanjing National Laboratory of Microstructures Nanjing University School of Chemistry The University of Sydney

Reaction of [mn（TTF-salphen）][OAc] （TTF-salphen2=2,2＇-（（2-（4,5-bis（methylthio）-1,3-dithiol-2-ylidene）-1,3-benzodithiole- 5,6-diyl）bis（nitrilomethylidyne）bis（pbenolate）dianion） and the cyanometalate building blocks [n-Bu4N][（Tp）Fe（CN）3] （Tp =Tris（pyrazolyl）hydroborate） or [n-Bu4N][Ru（salen）（CN）2] （salen2 =N,N＇-ethylenebis（salicylideneimine）dianion） resulted in the formation of two redox-active complexes, the dinuclear heterometallic complex [（Tp）Fe（CN）3mn（TTF-salphen）＇CH3OH] （1） and the one dimensional complex [Ru（salen）（CN）2mn（TTF-salphen）]n （2）. Both complexes were characterized by X-ray crystallography and solid state electrochemistry, in addition to static and dynamic magnetic measurements. Antiferromagnetic couplings are found to be operative between metal ion centers bridged by cyanide in both complexes. Complex 1 exhibited field-induced Smm behavior with an energy barrier of 13.8 K. The introduction of the redox-active TTF unit into cyanidebridged complexes with interesting magnetic properties renders them promising candidates for the construction of new hybrid inorganic-organic materials.

关键词： cyanide complexes single molecule magnets tetrathiafulvalene multifunctional materials

Towards a unified nonlocal, peridynamics framework for the coarse-graining of molecular dynamics data with fractures

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Applied mathematics and mechanics(English Edition) 2023年第7期44卷 1125-1150页

作者： H.Q.YOU X.XU Y.YU S.SILLING m.d'ELIA J.FOSTER department of mathematics Lehigh UniversityBethlehemPA 18015U.S.A department of Petroleum and Geosystems Engineering The University of Texas at AustinTX 78712-1139U.S.A. Center for Computing Research Sandia National LaboratoriesCA 94551-0969U.S.A.

molecular dynamics(md)has served as a powerful tool for designing materials with reduced reliance on laboratory ***,the use of md directly to treat the deformation and failure of materials at the mesoscale is still largely beyond *** this work,we propose a learning framework to extract a peridynamics m.del as a mesoscale continuum surrogate from md simulated material fracture data ***,we develop a novel coarse-graining method,to automatically handle the material fracture and its corresponding discontinuities in the md displacement data *** by the weighted essentially non-oscillatory(WENO)scheme,the key idea lies at an adaptive procedure to automatically choose the locally smoothest stencil,then reconstruct the coarse-grained material displacement field as the piecewise smooth solutions containing ***,based on the coarse-grained md data,a two-phase optimizationbased learning approach is proposed to infer the optimal peridynamics m.del with damage *** the first phase,we identify the optimal nonlocal kernel function from the data sets without material damage to capture the material stiffness ***,in the second phase,the material damage criterion is learnt as a smoothed step function from the data with *** a result,a peridynamics surrogate is *** a continuum m.del,our peridynamics surrogate m.del can be employed in further prediction tasks with different grid resolutions from training,and hence allows for substantial reductions in computational cost compared with *** illustrate the efficacy of the proposed approach with several numerical tests for the dynamic crack propagation problem in a single-layer *** tests show that the proposed data-driven m.del is robust and generalizable,in the sense that it is capable of m.deling the initialization and growth of fractures under discretization and loading settings that are different from the ones used during training.

关键词： nonlocal m.del machine learning homogenization peridynamics material fracture

Environmental drivers and genomic architecture of trait differentiation in fire-adapted Banksia attenuata ecotypes

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Journal of Integrative Plant Biology 2019年第4期61卷 417-432页

作者： Tianhua He Byron B.Lamont Neal J.Enright Haylee m.d'Agui William Stock School of molecular and Life Sciences Curtin University School of Veterinary and Life Sciences Murdoch University Centre for Ecosystem management Edith Cowan University

Trait divergence between populations is considered an adaptive response to different environments,but to what extent this response is accompanied by genetic differentiation is less clear since it may be phenotypic plasticity. In this study, we analyzed phenotypic variation between two Banksia attenuata growth forms, lignotuberous(shrub) and epicormic resprouting(tree), in fire-prone environments to identify the environmental factors that have driven this phenotypic divergence. We linked genotype with phenotype and traced candidate genes using differential gene expression analysis. Fire intervals determined the phenotypic divergence between growth forms in B. attenuata. A genome-wide association study identified 69 single nucleotide polymorphisms, putatively associated with growth form, whereas no growth form-or phenotype-specific genotypes were eidentified. Genomic differentiation between the two growth forms was low(F_(st)=0.024). differential gene expression analysis identified 37 genes/transcripts that were differentially expressed in the two growth forms. A small heat-shock protein gene, associated with lignotuber presence, was differentially expressed in the two *** conclude that different fire regimes induce phenotypic polymorphism in B. attenuata, whereas phenotypic trait divergence involves the differential expression of a small fraction of genes that interact strongly with the disturbance regime. Thus, phenotypic plasticity among resprouters is the general strategy for surviving varying fire regimes.

关键词： Environmental drivers genomic architecture trait differentiation

diabetic Gastroparesis

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胃肠病学 2000年第B8期5卷 35-36页

作者： ChungOwyang,m.d Universityofmichiganm.dicalCenter USA

diabetic gastroparesis occurs in about 30% of patients with type 1 diabetes. delays in emptying of solid foods are generally believed to result from impaired phasic antral motor activity and this may result in early postprandial fullness, nausea and vomiting. Both phase Ⅲ of the interdigestive migrating motor complex and phasic activities of the postprandial antral motility are impaired in diabetic gastroparesis. Although these abnormalities are believed to be a result of neuropathy, the actual abnormalities in the neural circuitry responsible for gastroparesis remain to be defined. Neuropathy may affect various neural pathways differentially.

关键词：糖尿病胃疾病活动性呕吐

SLEEP dISORdERS, SLEEP APNEA. ANd STROKE

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中国临床神经科学 2000年第Z1期8卷 36-45页

作者： ANTONIO CULEBRAS, m.d

　　Sleep is the natural suspension of consciousness during which the powers of the body are restored Sleep recurs with remarkable periodicity in alliance with the geocosmic cycle and in compliance with the circadian ...

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