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Journal of Advanced Ceramics 2019年第2期8卷 238-246页

作者： Evando s.ARAuJo Victor N.s.LEAo Research Group on Electrospinning and Nanotechnology Applications(GPEA-Nano) Department of Materials ScienceUniversidade Federal do Vale do Sao Francisco

Relative humidity(RH) is a critical environmental variable for transportation and storage of products and for the quality guarantee of several other production processes and services. Heterogeneous structures prepared from the selective semiconductor oxides may improve the sensitivity to humidity due to the better electronic and surface properties, when compared to pristine oxides. This work shows an alternative fabrication route for producing titanium dioxide/tungsten trioxide(Tio2/Wo3) heterogeneous structures(by electrospinning and sintering) for potential application on the RH detection. The microstructural properties of the materials were analyzed by scanning electron microscopy(sEM), energy dispersive X-ray analysis(EDs), X-ray diffraction, and Raman spectroscopy. The electrical characterization of the structures was performed by electrical impedance spectroscopy in RH range of 10%–100%. Results indicated a p-to n-type conduction transition at around 30%–40% RH for all tested settings. The analysis of the impedance signature to humidity showed that the amount of fiber layers on the electrode and working temperature are important parameters to improve the humidity sensing of the Tio2/Wo3 systems.

关键词： electrospinning heterogeneous structures preparation relative humidity semiconductors

Carbon dots-doped Electrospun Fibers for simultaneous Metal Ion Detection and Adsorption of Dyes

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Advanced Fiber Materials 2020年第6期2卷 302-313页

作者： Mário César A.de oliveira Elisângela G.de L.oliveira Indira C.B.Pires Iuri C.M.Candido Nikifor Rakov Helinando P.de oliveira Yutao Xing Glauco s.Maciel Institute of Materials science Universidade Federal do Vale do São FranciscoJuazeiroBA 48920-310Brazil Instituto de Física Universidade Federal FluminenseNiteróiRJ 24210-346Brazil

The required treatment and monitoring of contaminants in wastewater reinforces the development of low-cost adsorbents/chemosensors,introducing advantages relative to the detection/removal of toxic metals and ***,it is reported a two-step process of fabrication of fluorescent carbon dots via the hydrothermal treatment of amino acids for the following encapsulation in electrospun *** prominent anionic behavior of electrospun fibers of Eudragit L100 was explored for adsorption of cationic dyes(methylene blue and crystal violet)-with the prevailing electrostatic interaction of parts being favored by the formation of monolayers on the surface of *** the other hand,the controlled release of carbon dots(CDs)from fibers to the reactor can be explored for a second application:the nitrogen ligands from released glycine-based carbon dots can be explored to indicate the presence of metal ions in aqueous *** experiment resulted in a quenching in the fluorescence of the CDs in order of 90%in the emission of particles in the response of the presence of Fe^(3+) ions,characterizing a promising perspective for this experimental system.

关键词： Fluorescence Ferric ion detection Electrospinning Carbon nanostructure

Andean orogenic signature in the Quaternary sandy barriers of southernmost Brazilian Passive Margin – Paradigm as a source area

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Geoscience Frontiers 2021年第4期12卷 61-70页

作者： Farid Chemale Junior Ernesto Luiz Correa Lavina Julierme Justin Carassai Tiago Jonatan Girelli Cristiano Lana Programa de Pós Graduação em Geologia Universidade do Vale do Rio dos Sinos93022-220São LeopoldoRSBrazil Departamento de Geologia Universidade Federal do Ouro Preto35400-000Morro do CruzeiroOuro PretoMGBrazil

Multiple source provenance of sediments and submarine fan formation are herein investigated based on Quaternary sandy barriers of the Brazilian southernmost Coastal ***-ICP-Ms dating on 1625 detrital zircons from marine and aeolian facies sands of four successive lagoon-barrier systems are *** characterization of Archean to Pleistocene zircons into a younger Andean(22±4 Ma to 1±1 Ma,48 from 1625),Mesozoic to Paleozoic,and Mesoproterozoic(479 from 1622)populations suggest that the main feeding of sediments to the coastal plain occurred through the La Plata River drainage *** significant contribution of sediments is transported from the mouth of La Plata River northward by longshore circulation(littoral drift).Minor contributions are also recognized as.a farther source associatedwith the Patagonia drainage and nearby source related to the Uruguay/Rio Grande do sul shield and the ParanáBasin,drained by the Camaquãand Jacuí*** latter one is recognized by the contribution fromNeoproterozoic to Early Paleozoic,and some Paleoproterozoic and Archean zircon *** definition of the sources of clastic sediments allows inferences about the origination of Rio Grande Fan where both the cold Falkland and the warm Brazil currents played a major role.

关键词： U–Pb zircon Coastal plain Andean provenance source to sink process Rio Grande Fan ocean Atlantic

Gain of transcription factor binding sites is associated to changes in the expression signature of human brain and testis and is correlated to genes with higher expression breadth

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science China(Life sciences) 2019年第4期62卷 526-534页

作者： Vandeclécio Lira da silva André Mauricio Ribeiro dos santos Wilfredo Blanco sandro José de souza Bioinformatics Multidisciplinary Environment (BioME) Universidade Federal do Rio Grande do Norte (UFRN) Programa de Pós-Gradua??o em Genética e Biologia Molecular (PPGBM) Universidade Federal do Pará (UFPA) Department of Computer science Universidade Estadual do Rio Grande do Norte (UERN) Brain Institute Universidade Federal do Rio Grande do Norte (UFRN)

The gain of transcription factor binding sites(TFBs) is believed to represent one of the major causes of biological *** we used strategies based on comparative genomics to identify 21,822 TFBs specific to the human lineage(TFBs-Hs),when compared to chimpanzee and gorilla genomes. More than 40%(9,206) of these TFBs-Hs are in the vicinity of 1,283 genes.A comparison of the expression pattern of these genes and the corresponding orthologs in chimpanzee and gorilla identified genes differentially expressed in human tissues. These genes show a more divergent expression pattern in the human testis and brain, suggesting a role for positive selection in the fixation of TFBs gains. Genes associated with TFBs-Hs were enriched in gene ontology categories related to transcriptional regulation, signaling, differentiation/development and nervous ***, genes associated with TFBs-Hs present a higher expression breadth when compared to genes in general. This biased distribution is due to a preferential gain of TFBs in genes with higher expression breadth rather than a shift in the expression pattern after the gain of TFBs.

关键词： TFBs transcript factor human evolution expression breadth

U-Pb provenance fingerprints of metavolcanic-sedimentary successions of the Mineiro belt:Proxies for the continuity of plate tectonics through the Paleoproterozoic

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Geoscience Frontiers 2022年第5期13卷 309-335页

作者： W.Teixeira C.A.Ávila I.A.Dussin E.Bongiolo Instituto de Geociências Universidade de São PauloBrazil Museu Nacional Universidade Federal do Rio de JaneiroBrazil Faculdade de Geologia Universidade do Estado do Rio de JaneiroBrazil Programa de Pós-graduação em Geociências Instituto de GeociênciasUniversidade Federal do Rio Grande do SulBrazil

We document new U-Pb detrital zircon LA-MC-ICP-Ms data for seven metavolcanic-sedimentary successions and metasedimentary sequences and reassess additional dates of five siliciclastic samples toward their tectonic significance in the context of the Mineiro belt,southern são francisco *** belt represents a crustal segment of the 2.47–2.00 Ga Minas orogen,classically known by its siderian and Rhyacian juvenile rocks with important implications in the Earth’s *** new and compiled detrital provenance constraints unravel the long-lived magmatic and sedimentary history of the studied basins,lasting ca.230–220 *** maximum depositional dates around 2.1 Ga reflect the renewed sediment budget with the subsequent metamorphic episode ca.2.0 *** of the unmixed relative probability diagrams are consistent with sourcing from the siderian and Rhyacian arcs of the Mineiro belt,determining a detrital provenance change in time and space for the precursor *** potential sources could be the youngest rocks of the Mantiqueira and Juiz de Fora terranes that constitute the other segments of the Minas orogen,given the age *** overall detrital fingerprints determine the study basins resumed mainly in Rhyacian fore-arc and/or back-arc settings,i.e.,akin to a subductionrelated system that evolved to a collisional(foreland)*** samples show fingerprints of primary extensional settings,determined by major Archean detrital populations sourced from areas outside the Mineiro belt beside the Paleoproterozoic *** working model considers the collage between the Mineiro belt and the ancient foreland around 2.10 Ga and eventual interaction with other crustal segments of the Minas orogen,generating the ca.2.0 Ga metamorphism over the metasedimentary *** more complete isotopic repository in detrital and igneous zircon grains for the studied supracrustal successions and the associated rocks allows new insights into the Rhyacian–oro

关键词： Paleoproterozoic são francisco Craton Detrital zircon geochronology Metavolcanic-sedimentary basin

Rotating effects on the photoionization cross-section of a 2D quantum ring

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Communications in Theoretical Physics 2024年第10期76卷 151-157页

作者： Carlos Magno o Pereira Frankbelson dos s Azevedo Luís Fernando C Pereira Edilberto o silva Departamento de Física Universidade Federal do Maranhão65085-580 São LuísMaranhãoBrazil

In this article,we investigate the nonrelativistic quantum motion of a charged particle within a rotating frame,taking into account the Aharonov–Bohm(AB)effect and a uniform magnetic *** analysis entails the derivation of the equation of motion and the corresponding radial equation to describe the *** the resulting radial equation enables us to determine the eigenvalues and eigenfunctions,providing a clear expression for the energy ***,our numerical analysis highlights the substantial influence of rotation on both energy levels and optical ***,we evaluate the photoionization cross-section with and without the effects of *** elucidate the impact of rotation on the photoionization process of the system,we present graphics that offer an appealing visualization of the intrinsic nature of the physics involved.

关键词： photoionization cross-section rotating effect quantum ring Aharonov–Bohm effect

Bird habitat preferences drive hemoparasite infection in the Neotropical region

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Integrative Zoology 2021年第5期16卷 755-768页

作者： Gabriel Massaccesi DE LA ToRRE Karla Magalhães CAMPIÃo Biological Interactions Departamento de ZoologiaUniversidade Federal do ParanáCuritibaBrazil Programa de Pós-graduação em Ecologia e Conservação Universidade Federal do ParanáCuritibaBrazil

The role that the environment plays in vector-borne parasite infection is one of the central factors for understanding disease *** assessed how Neotropical bird foraging strata and habitat preferences determine infection by parasites of the genera Haemoproteus,Plasmodium,Leucocytozoon,and Trypanosoma and filarioids,and tested for phylogenetic signal in these host-parasite *** performed extensive searches of the scientific literature and created a database of hemoparasite *** collected data on host body mass,foraging strata,habitat preference,and migratory status,and tested if host ecological traits predict each hemoparasite occurrence and prevalence using a phylogenetic Bayesian *** of Plasmodium tend to infect birds from tropical forests while birds from altitudinal environments are likely to be infected by species of *** probability of a bird being infected by filarioid or Trypanosoma is higher in lowland *** species that occur in anthropic environments and dry habitats of tropical latitudes are more susceptible to infection by species of *** foraging strata is also influential and bird species that forage in the mid-high and canopy strata are more prone to infection by species of Haemoproteus and *** also identified phylogenetic signal for host-parasite associations with the probability of infection of Neotropical birds by any hemoparasite being more similar among more closely related *** provided a useful framework to identify environments that correlate with hemoparasite infection,which is also helpful for detecting areas with potential suitability for hemoparasite infection due to land conversion and climate change.

关键词： habitat use haemosporidians host-parasite interaction migratory birds prevalence

Choosing among correlative, mechanistic, and hybrid models of species’ niche and distribution

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Integrative Zoology 2023年第1期18卷 93-109页

作者： Luara ToURINHo Mariana M.vale Graduate Program in Ecology Universidade Federal do Rio de JaneiroIlha do FundãoRio de JaneiroBrazil Ecology Department Universidade Federal do Rio de JaneiroIlha do FundãoRio de JaneiroBrazil

Different models are available to estimate species’niche and *** and correlative models have different underlying conceptual bases,thus generating different estimates of a species’niche and geographic *** models,which combining correlative and mechanistic approaches,are considered a promising strategy;however,no synthesis in the literature assessed their applicability for terrestrial vertebrates to allow best-choice model considering their strengths and ***,we provide a systematic review of studies that compared or integrated correlative and mechanistic models to estimate species’niche for terrestrial vertebrates under climate *** goal was to understand their conceptual,methodological,and performance differences,and the appli-cability of each *** studies we reviewed directly compared mechanistic and correlative predictions in terms of accuracy or estimated suitable area,however,without any quantitative analysis to support ***,many studies suggest that instead of comparing approaches,mechanistic and correlative methods should be integrated(hybrid models).However,we stress that the best approach is highly ***-deed,the quality and effectiveness of the prediction depends on the study’s objective,methodological design,and which type of species’niche and geographic distribution estimated are more appropriate to answer the study’s issue.

关键词： climate change ecological niche model integrative model species distribution model vertebrates

Fern extracts potentiate fluconazole activity and inhibit morphological changes in Candida species

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Asian Pacific Journal of Tropical Biomedicine 2017年第11期7卷 1025-1030页

作者： Maria A.Freitas Antonia T.L.santos Antonio J.T.Machado Ana Raquel P.silva Fábia F.Campina Maria s.Costa Gioconda M.A.B.Martins Maria Flaviana B.Morais-Braga saulo R.Tintino Irwin R.A.Menezes Jaime Ribeiro-Filho Altevir P.Medeiros Adeliana s.oliveira Patrício B.Maracajá Henrique D.M.Coutinho universidade Regional do Cariri-URCA universidade federal Rural do semi-A′rido-UFERsA universidade federal do Rio Grande do Norte-UFRN universidade federal de Campina Grande-UFCG

objective: To investigate the antifungal activity of the fern species Lygodium venustum(L. venustum) and Pityrogramma calomelanos(P. calomelanos) against Candida albicans and Candida tropicalis ***: The microdilution method was used to evaluate the antifungal activity, as well as the modulating effects of ethanolic extracts of these plants in combination with fluconazole. The minimum inhibitory concentration(MIC), minimum fungicide concentration and morphological changes were also ***: The extract obtained from L. venustum presented a MIC > 8 192 mg/m L, while the extract obtained from and P. calomelanos presented a MIC = 8 192 mg/m L, indicating that they present weak antifungal activity. However, combination of the extracts with Fluconazole potentiated the antifungal activity of this drug. At different experimental conditions, such as concentration of the extract and type of strain, the extracts inhibited hyphae and pseudohyphae formation, indicating that these fern species can affect the morphology of the ***: The extracts obtained from the fern species L. venustum and P. calomelanos dose not present significant antifungal activity. However, P. calomelanos potentiates the activity of fluconazole and both extracts inhibits the morphological changes in Candida species, indicating that they have potential pharmacological activity as modulators of fungal biology. Therefore, novel studies are required to characterize the interference of these extracts in the virulence and pathogenicity of Candida species as well as the potential of fern species to treat fungal infections.

关键词： Dimorphism Candida species Ferns Lygodium venustum Pityrogramma calomelanos

New patterns of the tree beta diversity and its determinants in the largest savanna and wetland biomes of south America

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Plant Diversity 2023年第4期45卷 369-384页

作者： Karla J.P.silva-souza Maíra G.Pivato Vinícius C.silva Ricardo F.Haidar Alexandre F.souza Departamento de Ecologia Universidade Federal do Rio Grande do NorteRNBrazil Curso de Engenharia Ambiental Universidade Federal do TocantinsTOBrazil

Clear and data-driven bioregionalizations can provide a framework to test hypotheses and base biodiversity *** we used occurrence and abundance data in combination with objective analytical methods to propose two bioregionalization schemes for tree species of the Cerrado and the Pantanal in south *** also evaluated the contribution of three sets of determinants of the occurrence-and abundance-based *** compiled data on tree species composition from 894 local assemblages based on species occurrences,and from 658 local assemblages based on species *** used an unconstrained community-level modelling approach and clustering techniques to identify and map tree subregions for the occurrence and the abundance data sets,*** clustering analyses were conducted to investigate floristic affinities between the subregions and to map broader floristic *** used multinomial logistic regression models,deviance partitioning,and rank-sum tests to assess the main subregion *** identified 18 occurrence-and four abundance-based subregions in the *** hierarchical classifications grouped the occurrence-based subregions into nine floristic zones and abundance-based subregions into two broad floristic *** in subregions were explained mainly by environmental factors and spatial structure in both occurrence and abundance data *** occurrence-and abundance-based subregions are complementary approaches to disentangle macroecological patterns and to plan conservation efforts in the Cerrado and the *** findings based on occurrence data revealed more complex and interdigitated boundaries between subregions of tree species than previously *** environment,historical stability,and human effects act in a synergetic way on the distribution of the ***,the relevance of contemporary environmental factors to the subregion patterns we found alert us to the profound im

关键词： Cerrado Pantanal savanna Biogeographical regionalization Biodiversity hotspot south America