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Arlenea delicata *** ***.,a new ephedroid plant from the early Cretaceous Crato Formation,Araripe Basin,Northeast Brazil

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Plant Diversity 2024年第3期46卷 362-371页

作者： Alita Maria Neves Ribeiro Yong Yang Antonio Alamo Feitosa Saraiva Renan Alfredo Machado Bantim Joao Tavares Calixto Junior Flaviana Jorge de Lima Programa de Pos-Graduaçao em Diversidade Biologica e Recursos naturais Universidade Regional do CaririRua Carolino SucupiraPimenta63105-160CratoCearaBrazil Co-Innovation Center for Sustainable Forestry in Southern China College of Biology and the Environment159 Longpan RoadNanjing Forestry UniversityNanjing210037China Laboratorio de Paleontologia Universidade Regional do CaririRua Carolino SucupiraPimenta63105-160CratoCearaBrazil Laboratorio de estudos da Flora Regional Universidade Regional do CaririRua Carolino SucupiraPimenta63105-160CratoCearaBrazil Gondwanan Plants Lab Universidade Federal de PernambucoCentro Academico de VitoriaRua Do Alto Reservatorio S/nBela Vista55608-680Vitoria de Santo AntaoPernambucoBrazil Programa de Pos-Graduaçao em Geociencias(PPGeOC) Universidade Federal de Pernambuco(UFPE)Rua Av.da ArquiteturaS/n°CEP-50740-550Cidade UniversitariaRecifePernambucoBrazil

ephedroid macrofossils have been widely documented in Cretaceous deposits,including numerous from the Lower Cretaceous Yixian Formation of Ne ***,few ephedroid macrofossils have been reported from South ***,we describe a new plant of the family ephedraceae,Arlenea delicata *** ***.,from the Lower Cretaceous Crato Formation of the Araripe Basin,Northeast Brazil,based on the vegetative and reproductive *** has the typical morphological characteristics of ephedroid plants,including fertile reproductive branches,opposite phyllotaxy,terminal female cones,a sympodial branching system,longitudinally striated internodes,and swollen *** new finding is unusual in having inner chlamydosperms subtended by two pairs of bracts,reproductive units connected to branches through swollen receptacles and a smooth seed *** new ephedroid taxon from the Crato Formation increases our understanding of plant diversity of this group during the early ***,the general morphology(fleshy bracts and enlarged receptacles)of this new fossil discovery indicates that seeds of this plant may have been dispersed by animals such as pterosaurs(mainly the Tapejaridae)and birds(enantiornithes and Ornituromorpha).If true,this would explain the cosmopolitan distribution of ephedraceae in the Lower Cretaceous.

关键词： early Cretaceous Gnetophytes Arlenea delicata ephedrales Crato Formation

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experimental evidence of pressure effects on spinel dissolution and peridotite serpentinization kinetics under shallow hydrothermal conditions

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Geoscience Frontiers 2024年第2期15卷 236-250页

作者： Yuri de Melo Portella Rommulo Vieira Conceição Tiago Abreu Siqueira Lucas Bonan Gomes Rodrigo Sebastian Iglesias Programa de Pós-Graduação em Geociências(PPGGeO) Universidade Federal do Rio Grande do SulPorto AlegreBrazil Petrobras–Petróleo Brasileiro S.A. Avenida Henrique Valadares 28CentroRio de Janeiro(RJ)20231-030Brazil Instituto do Petróleo e dos Recursos naturais-PUCRS–Pontifícia Universidade Católica do Rio Grande do Sul 90619-900Porto AlegreBrazil Universidade Federal do Rio Grande do Sul Instituto de GeociênciasLaboratório de Difratometria de Raios XPorto AlegreBrazil escola Politécnica–PUCRS-Pontifícia Universidade Católica do Rio Grande do Sul 90619-900 Porto AlegreBrazil

Serpentinization reactions are paramount to understand hydro-geothermal activity near plate boundaries and mafic–ultramafic massifs,as well as fluid and element transfer between the earth’s mantle and ***,fluid-rock element exchange and serpentinization kinetics under shallow hydrothermal conditions is still largely *** we present two constant temperature(230℃)time-series of natural peridotite(77.5%olivine;13.7%enstatite;6.8%diopside;2%spinel)serpentinization experiments:at 13.4 MPa;and 20.7 ***-enriched lizardite was the main secondary mineral in all runs after olivine(olv)and orthopyroxene(opx)serpentinization(without any detectable brucite,talc or magnetite),while primary spinel and diopside partially dissolved during the *** serpentinization stages comprises intrinsically coupled reactions between olivine and enstatite,as Al and Si are progressively transferred from orthopyroxene-derived to olivine-derived serpentine,while the opposite is true for Mg and Fe,with homogenization of serpentines compositions after 40 *** Ni/Cr ratios of serpentines,however,remain diagnostic of the respective primary *** average serpentine content indicates fast serpentinization rates of 0.55 wt.%·day^(-1)(0.26 mmol·day^(-1))and 0.26 wt.%·day^(-1)(0.13 mmol·day^(-1))at 13.4 and 20.7 MPa,*** 2x faster serpentinization kinetics at lower pressure is likely linked to enhanced spinel dissolution leading to one order of magnitude higher available Al,which accelerates olivine serpentinization while delays orthopyroxene ***,time-dependent increase in solid products masses suggests rock volume expands linearly 0.37%±0.01%per serpentine wt.%independently of *** balance constrains suggests olv:opx react at~5:2 and~3:2 M ratios,resulting in Si-deficient and Si-saturated serpentines at the end of the low-pressure series(13.4 MPa)and high-pressure series(20.7 MPa),***

关键词： Serpentine Volume expansion Serpentinization fluids Lost city hydrothermal field Serpentinite-hosted hydrothermal systems Hydrogen(H_(2))generation

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Climatic niche breadths of the Atlantic Forest snakes do not increase with increasing latitude

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Current Zoology 2022年第5期68卷 535-540页

作者： José Thales da Motta Portillo Fausto erritto Barbo Ricardo J.Sawaya Programa de Pós-Graduação em Biologia Animal Instituto de BiociênciasLetras e Ciências ExatasUniversidade Estadual Paulista“Júlio de Mesquita Filho”Rua Cristóvão Colombo2265São Josédo Rio PretoSão Paulo 15054-000BrazilLaboratório de Coleções ZoológicasInstituto ButantanAvenida Vital Brazil1500São Paulo 05503-900Braziland Centro de Ciências Naturais e HumanasUniversidade Federal do ABCRua Arcturus03São Bernardo do CampoSão Paulo 09606-070Brazil

The climatic niche is a central concept for understanding species distribution,with current and past climate interpreted as strong drivers of present and historical-geographical *** aim is to understand whether Atlantic Forest snakes follow the general geographical pattern of increasing species climatic niche breadths with increasing *** also tested if there is a tradeoff between temperature and precipitation niche breadths of species in order to understand if species with larger breadths of one niche dimension have stronger dispersal constraints by the other due to narrower niche *** breadths were calculated by the subtraction of maximal and minimal values of temperature and precipitation across species *** implemented Phylogenetic Generalized Least Squares to measure the relationship between temperature and precipitation niche breadths and *** also tested phylogenetic signals by Lambda statistics to analyze the degree of phylogenetic niche conservatism to both niche *** niche breadths were not related to *** niche breadths decreased with increasing latitude and presented a high phylogenetic signal,that is,significant phylogenetic niche *** rejected the tradeoff hypotheses of temperature and precipitation niche *** results also indicate that precipitation should be an important ecological constraint affecting the geographical distribution of snake lineages across the South American Atlantic *** then provide a general view of how phylogenetic niche conservatism could impact the patterns of latitudinal variation of climatic niches across this biodiversity hotspot.

关键词： Atlantic Forest biogeography climatic niche latitudinal gradient snakes

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3D city Models as a Visual Support Tool for the Analysis of Buildings Seismic Vulnerability: The Case of Lisbon

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International Journal of Disaster Risk Science 2017年第3期8卷 308-325页

作者： Paula Redweik Paula Teves-Costa Inês Vilas-Boas Teresa Santos Instituto Dom Luiz Faculdade de CiênciasUniversidade de Lisboa eSRI Portugal ciCS.NOVA–centro Interdisciplinar de ciências Sociais Faculdade de Ciências Sociais e HumanasUniversidade Nova de Lisboa

3D city models associate a database of a city to a rigorous geospatial representation that is close to the visible reality by combining appearance, geometry, and semantics. As such, these models may include tools that convey attribute analysis, not only at the statistical level but also in terms of visual appearance of the objects, thus allowing the generation of new knowledge about a phenomenon or its effects. Lisbon is a city with a moderate level of seismic risk, and has been hit in the past by strong earthquakes. Several seismic vulnerability studies of buildings have been carried out in Lisbon. These studies generate different scenarios that consider the magnitude and source location of potential earthquakes. The results of these studies were presented as maps obtained from crossing information contained in 2D layers and presented in a GIS environment. In the present study a seismic vulnerability assessment of Lisbon's buildings held in 2D is extended to the third dimension, which refines the resolution and the set of parameters and explores the gains of spatial analysis in 3D representations. The numerous parameters that contribute to assess seismic vulnerability of buildings may be analyzed individually or simultaneously as well as in multiple seismic scenarios. Although covering all residential buildings in Lisbon, the application of the 3Dcity model is demonstrated with more detail in three pilot areas.

关键词： 3D-GIS 3D 当模特儿大楼危险葡萄牙首都地震情形

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Modeling the crystallographic structure of Ho(Ni,Co,Mn)O_(3±δ) perovskite-type manganite

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Journal of Advanced Ceramics 2012年第4期1卷 274-282页

作者： C.Morilla-Santos F.F.Ferreira W.H.Schreiner O.Peña P.N.Lisboa-Filho UNeSP-Univ estadual Paulista POSMAT-Programa de Pós-Graduação em Ciência e Tecnologia de MateriaisBauruBrazil UFABC-Universidade Federal do ABC-centro de ciências naturais e humanas Santo AndréBrazil UFPR-Universidade Federal do Paraná Departamento de FísicaCuritibaBrazil Sciences Chimies de Rennes UMR 6226 Universitéde Rennes 1RennesFrance UNeSP-Univ estadual Paulista Faculdade de CiênciasDepartamento de FísicaBauruBrazil

Crystallographic and microstructural properties of Ho(Ni,Co,Mn)O3±dperovskite-type multiferroic material are *** were synthesized with a modified polymeric precursor *** synchrotron X-ray powder diffraction(SXRPD)technique associated to Rietveld refinement method was used to perform structural *** crystallographic structures,as well as microstructural properties,were studied to determine unit cell parameters and volume,angles and atomic positions,crystallite size and strain.X-ray energies below the absorption edges of the transition metals helped to determine the mean preferred atomic occupancy for the substituent ***,analyzing the degree of distortion of the polyhedra centered at the transitions metal atoms led to understanding the structural model of the synthesized phase.X-ray photoelectron spectroscopy(XPS)was performed to evaluate the valence states of the elements,and the tolerance factor and oxygen *** obtained results indicated a small decrease distortion in structure,close to the HoMnO3 basis *** addition,the substituent atoms showed the same distribution and,on average,preferentially occupied the center of the unit cell.

关键词： crystallographic structure X-ray powder diffraction Rietveld refinement manganites

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Fast Radio Bursts as Crustal Dynamical events Induced by Magnetic Field evolution in Young Magnetars

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Research in Astronomy and Astrophysics 2022年第3期22卷 39-46页

作者： J.e.Horvath P.H.R.S.Moraes M.G.B.de Avellar L.S.Rocha Universidade de São Paulo(USP) Instituto de AstronomiaGeofísica e Ciências AtmosféricasRua do Matão 1226Cidade Universitária05508-090 São PauloSPBrazil Universidade Federal de São Paulo(UNIFeSP) Instituto de Ciências AmbientaisQuímicas e FarmacêuticasRua São Nicolau 21009913-030 DiademaSPBrazil Universidade Federal do ABC(UFABC) Centro de Ciências Naturais e Humanas(CCNH)Avenida dos Estados 500109210-580Santo AndréSPBrazil

We revisit in this work a model for repeating Fast Radio Bursts based of the release of energy provoked by the magnetic field dynamics affecting a magnetar’s *** address the basics of such a model by solving the propagation of the perturbation approximately,and quantify the energetics and the radiation by bunches of charges in the so-called charge starved region in the ***(almost)simultaneous emission of newly detected X-rays from SGR 1935+2154 is tentatively associated with a reconnection behind the *** strength of f-mode gravitational radiation excited by the event is quantified,and more detailed studies of the nonlinear(spiky)soliton solutions are suggested.

关键词： stars:magnetars relativistic processes radiation mechanisms:non-thermal

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Asymmetric hydrogenation and transfer hydrogenation in the enantioselective synthesis of flavonoids

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Organic Chemistry Frontiers 2022年第4期9卷 1165-1194页

作者： Guilherme S.Caleffi Felipe C.demidoff Carmen Najera Paulo R.R.Costa Laboratorio de Quimica Bioorganica(LQB) Instituto de Pesquisas de Produtos NaturaisUniversidade Federal do Rio de JaneiroAv.Carlos Chagas Filho 373Bloco HCidade Universitaria21941-902 Rio de Janeiro centro de Innovacion en Quimica Avanzada(ORFeO-ciNQA) Universidad de AlicanteApdo.99E-03080 AlicanteSpain

Asymmetric hydrogenation(AH)and asymmetric transfer hydrogenation(ATH)are versatile synthetic methodologies widely employed in the preparation of chiral *** this review,we explore the applications of AH and ATH in the total synthesis of natural flavonoids and their analogues,highlighting the limitations and opportunities in the field.

关键词： compounds field hydrogenation

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ecophysiology and multivariate analysis for production of Tachigali vulgaris in Brazil:Influence of rainfall seasonality and fertilization

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林业研究:英文版 2023年第5期34卷 1289-1305页

作者： Pedro Henrique Oliveira Simoes Candido Ferreira de Oliveira Neto Manoel Tavares de Paula Dênmora Gomes de Araújo Rodrigo Silva do Vale Joao Olegário Pereira de Carvalho Universidade Federal de Mato Grosso Campus Universitario de SinopSinop 78550728Mato GrossoBrazil Universidade Federal Rural da Amazonia Campus BelemBelem 66077830ParaBrazil Universidade do estado do Para Centro de Ciencias Naturais e TecnologiaBelem 66095015ParaBrazil Universidade Federal Rural da Amazonia Campus Capitao-PocoCapitao Poco 68650000ParaBrazil

Studies on fertilization management of species native to the Amazon for energy plantations contribute to the diversity of species use and reduce biological risk due to the excessive use of clones or hybrids of *** study evaluates the effect of precipitation seasonality and phosphorus and potassium fertilization on gas exchange in a Tachigali vulgaris *** levels of P(zero,65.2,130.4 kg ha^(-1))and three of K(zero,100.0,200.0 kg ha^(-1))were applied in a 3×3 factorial randomized block *** exchange measurements were conducted in April and November *** low rainfall,high irradiance period,photo synthetic rates were up to four times higher than in the high rainfall period,reaching 20.3μmol m^(-2)s^(-1)in the treatment with 130.4 g kg^(-1)of P and 100.0 g kg^(-1)of *** analysis and principal component analysis reduced the initial eight gas exchange variables to two and three principal components in periods of high and low rainfall,*** multivariate method used in this study readily identified variations in the variables as a function of rainfall,with high reliability in explaining the data set.

关键词： Photosynthesis rate Stomatal conductance Principal component analysis Factor analysis Tachigali vulgaris

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Species delimitation based on diagnosis and monophyly, and its importance for advancing mammalian taxonomy

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Zoological Research 2018年第5期39卷 301-308页

作者： eliécer e.Gutiérrez Guilherme S.T.Garbino Pós-Graduacao em Biodiversidade Animal Departamento de Ecologia e Evolucao Centro de Ciências Naturais e Exatas Universidade Federal de Santa Maria Santa Maria RS 97105-900 Brazil Division of Mammals National Museum of Natural History Smithsonian Institution Washington DC 20013-7012 USA Pós-graduacao Departamento de Zoologia Instituto de Ciências Biológicas Universidade Federal de Minas Gerais Belo Horizonte Minas Gerais 31270-901 Brazil

A recently proposed taxonomic classification of extant ungulates sparked a series of publications that criticize the Phylogenetic Species Concept （PSC） claiming it to be a particularly poor species *** opinions reiteratively stated that （1） the two fundamental elements of the ＂PSC＂,i.e.,monophyly and diagnosability,do not offer objective criteria as to where the line between species should be drawn;and （2） that extirpation of populations can lead to artificial diagnosability and spurious recognitions of *** sudden eruption of criticism against the PSC is *** attributed to the PSC are common to most approaches and concepts that modern systematists employ to establish species *** controversial taxonomic propositions that sparked criticism against the PSC are indeed highly problematic,not because of the species concept upon which they are based,but because no evidence （whatsoever） has become public to support a substantial portion of the proposed *** herein discuss these topics using examples from *** areas of biological research rest upon taxonomic accuracy （including conservation biology and biomedical research）;hence,it is necessary to clarify what are （and what are not）the real sources of taxonomic inaccuracy.

关键词： Alpha taxonomy Phylogenetic SpeciesConcept Species concepts Taxonomic inertia Taxonomic inflation

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Antioxidant effects of Phyllanthus niruri tea on healthy subjects

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Asian Pacific Journal of Tropical Medicine 2014年第2期7卷 113-118页

作者： elisngela Colpo Carlos D.D.A.Vilanova Romaiana P.Pereira Luis Gustavo B.Reetz Liline Oliveira Iria L.G.Farias Aline A.Boligon Margareth L.Athayde Joo Batista T.Rocha departamento de Química Centro de Ciências Naturais e ExatasUniversidade Federal de Santa Maria(UFSM) Laboratrio de Anlises Clínicas Hospital UniversitrioUniversidade Federal de Santa Maria(UFSM) departamento de Farmcia Industrial Universidade Federal de Santa Maria(UFSM)

Objective:To investigate the potential antioxidant effects of Phyllanthus niruri(***)tea on healthy ***:Five non-smoking,male healthy volunteers,20 to 31 years *** *** subject was treated twice,following a randomized crossover fashion regarding the ingestion of *** infusion(5 g/750 mL)(tea group)or 750 mL of water(control group).Fasting venous blood samples were collected prior to and at 1.2 and 4 h after infusion *** were tested for plasmatic gallic acid and ascorbic acid levels,erythrocytic catalase and superoxide dismutase activities,and intracellular DCFH fluorescence in granulocytes,monocytes and ***:Catalase and superoxide dismutase activities were not altered by tea *** levels of gallic acid were significantly increased at1,2 and 4 h after *** ingestion and plasma ascorbic acid at 1 h after *** ***:Ingestion of *** tea is associated with a slight increase in antioxidant markers in human blood(ascorbic acid and gallic acid),which may contribute to its pharmacological effects.

关键词： Antioxidants Polyphenols Phyllanthus niruri Human Ascorbic acid Gallic acid

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