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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

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

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

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

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

Structure and genetic diversity of natural populations of Guadua weberbaueri in the southwestern Amazon,Brazil

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Journal of Forestry Research 2021年第2期32卷 755-763页

作者： Glória da Silva Almeida Leal Fabrício Assis Leal Hugo Teixeira Gomes Anderson Marcos de Souza Sabina Cerruto Ribeiro Jonny everson Scherwinski-Pereira centro Multidisciplinar Universidade Federal do AcreCruzeiro do SulAcreBrazil Universidade de Brasília BrasíliaDistrito FederalBrazil centro de ciências Biológicas e da Natureza Universidade Federal do AcreRio BrancoAcreBrazil centro de Pesquisa e Aplicação de Bambu e Fibras naturais Universidade de Brasília–CPAB/UnBBrasíliaDistrito FederalBrazil embrapa Recursos Genéticos e Biotecnologia Av.W5 Norte(final)PqEBBrasíliaDistrito Federal 70770-917Brazil

The Brazilian state of Acre has an extensive natural reserve of bamboo,making it one of the largest in loco gene *** aim of this study was to characterize the structure and genetic diversity of Guadua weberbaueri *** two populations,one native(FAPB)and the other anthropized(FAPBA),using ISSR *** results show that the FAPB population exhibited higher values for all estimates of population ***,the FAPBA population also showed high heterozygosity,corroborated by estimated gene flow(Nm=3.9)between the *** study of the association between Nei’s genetic distances and the geographic distances between the populations were significantly correlated(r=0.45,p=0.01),corroborated by the dendrogram revealing two distinct groups corresponding to the collection sites,without mixing classes between populations in the same *** for the coancestry coefficient,pairs of individuals in the first distance class were positive and significant,indicating that plants that are geographically closer share common alleles with a frequency greater than by chance,which means that there is a tendency that geographically closer individuals are *** presented similar genetic structure when the geographical distance between them was up to 56 m for FAPB and up to 156 m for *** was concluded that anthropized environments exhibit less genetic diversity than native environments,inferring risks for species conservation if appropriate and planned management techniques are not adopted.

关键词： Guadua Bamboo Genetic diversity Amazon rainforest Anthropized and native populations Underutilization plants

Purinergic signaling and human immunodeficiency virus/acquired immune deficiency syndrome: From viral entry to therapy

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World Journal of Virology 2015年第3期4卷 285-294页

作者： Daniela F Passos Maria Rosa C Schetinger Daniela BR Leal departamento de Microbiologia e Parasitologia Centro de Ciências da SaúdeUniversidade Federal de Santa Maria departamento de Bioquímica e Biologia Molecular Centro de Ciências Naturais e ExatasUniversidade Federal de Santa Maria

Human immunodeficiency virus(HIV) infection is a serious condition associated to severe immune dysfunction and immunodeficiency. Mechanisms involved in HIV-associated immune activation, inflammation and loss of CD4+ T cells have been extensively studied, including those concerning purinergic signaling pathways. Purinergic signaling components are involved in viral entry and replication and disease progression. Research involving the participation of purinergic signaling in HIV infection has been not only important to elucidate disease mechanisms but also to introduce new approaches to therapy. The involvement of purinergic signaling in the pathogenesis of HIV infection and its implications in the control of the HIV infection are reviewed in this paper.

关键词： Human immunodeficiency virus Purinergic signaling Immune activation Inflammation

Biochar Increases Diuron Sorption and Reduces the Potential Contamination of Subsurface Water with Diuron in a Sandy Soil

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Pedosphere 2019年第6期29卷 801-809页

作者： Fabiano APeTTeR Tamara SFeRReIRA Adilson PSINHORIN Larissa BLIMA Fernandes AALMeIDA Leandro PPACHeCO Alexandre FSILVA Universidade Federal de Mato Grosso Instituto de Ciências Agrárias e AmbientaisSinop 78557-267(Brazil Universidade Federal do Piauí Programa de Pós-Graduaçño em AgronomiaBom Jesus 64900-000(Brazil Universidade Federal de Mato Grosso Instituto de Ciencias NaturaisSociais e HumanasSinop 78557-267(Brazil Universidade Federal de Mato Grosso Instituto de Engenharia Agrícola e AmbientalRondonópolis 78735-000(Brazil embrapa Milho e Sorgo Sete Lagoas 35701-970(Brazil

The herbicide diuron is widely used in agricultural areas in Brazil, whereas it has high potential for subsurface water contamination due to its physicochemical characteristics. Recent studies have demonstrated the potential of biochar as a sorbent and possible pesticide leaching mitigation. The objective of this study was to investigate the long-term effect of biochar application on the kinetics of sorption and desorption of diuron in a Cerrado Haplic Plinthosol. Samples were collected in an experiment conducted in the field in a randomized block design consisting of the combination of two levels of fertilizer application (0 and 300 kg ha −1 of 5-25-15 formula of NPK fertilizers) and three doses of biochar (0, 16, and 32 Mg ha −1 ). The Freundlich isotherm accurately described the sorption of diuron in all treatments. Biochar application increased the sorption and reduced the desorption of diuron. This effect was attributed to the contribution of biochar to total organic carbon (C) and C in the humin fraction and to the increase in the reactivity of the humic acid and humin fractions, which was significantly highly correlated with the sorption coefficient ( K f ). A positive correlation between the partition coefficient of organic C and K f confirmed the importance of the soil organic compartment for the sorption of diuron. The higher diuron sorption and lower diuron desorption capacities of sandy soils after biochar application could reduce the potential risk of diuron leaching and contamination of subsurface water.

关键词： Herbicide Leaching Partition coefficient Persistence Pyrogenic carbon Soil organic matter Sorption coefficient

Post-treatment with plant extracts used in Brazilian folk medicine caused a partial reversal of the antiproliferative effect of glyphosate in the Allium cepa test

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BIOCeLL 2013年第2期37卷 23-28页

作者： VIVIANe DAL-SOUTO FReSCURA ANDRIeLLe WOUTeRS KUHN HAYWOOD DAIL LAUGHINGHOUSe IV JUÇARA TeReZINHA PARANHOS SOLANGe BOSIO TedeSCO department of Biology Centro de Ciências Naturais e Exatas(CCNE)Universidade Federal de Santa Maria(UFSM)Avenida Roraimanº1000Cep.97105-900CamobiSanta MariaRio Grande do SulBrasil Centre for Protein engineering Institute of Chemistry B6University of LiègeBelgium.

Species of the genus Psychotria are used for multiple purposes in Brazilian folk medicine,either as water infusions,baths or *** study was aimed to evaluate the genotoxic and antiproliferative effects of infusions of Psychotria brachypoda and *** on the Allium cepa *** to distilled water was used as a negative control,while exposure to glyphosate was used as a positive *** interaction of extracts(as a post-treatment)with the effects of glyphosate was also *** showed that glyphosate and the extracts of both *** and *** reduced the mitotic index as compared with the negative control(distilled water).Surprisingly,however,both extracts from *** and *** caused a partial reversal of the antiproliferative effect of glyphosate when used as a *** also induced the highest number of cells with chromosomal alterations,which was followed by that of *** ***,the extracts from *** did not show any signifi cant genotoxic ***-treatment of glyphosate-treated samples with distilled water allowed a partial recovery of the genotoxic effect of glyphosate,and some of the Psychotria extracts also did ***,post-treatment of glyphosatetreated samples with *** extracts induced a statistically signifi cant apoptotic *** is concluded that *** extracts show antiproliferative effects and are not genotoxic,while extracts of *** show a less potent antiproliferative effect and may induce chromosomal *** fi nding of a partial reversion of the effects of glyphosate by a post-treatment with extracts from both plants should be followed up.

关键词： medicinal plants Psychotria brachypoda Psychotria birotula cell proliferation apoptosis