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Journal of Environmental Sciences 2015年第6期27卷 217-227页

作者： Andressa Cristhy Buch Maria Elizabeth Fernandes Correia Daniel Cabral Teixeira Emmanoel vieira Silva-Filho departamento de Geoquímica Universidade Federal Fluminense Embrapa Agrobiologia BR 465 km 7

The increasing levels of mercury（Hg） found in the atmosphere arising from anthropogenic sources, have been the object of great concern in the past two decades in industrialized countries. Brazil is the seventh country with the highest rate of mercury in the *** major input of Hg to ecosystems is through atmospheric deposition（wet and dry）, being transported in the atmosphere over large distances. The forest biomes are of strong importance in the atmosphere/soil cycling of elemental Hg through foliar uptake and subsequent transference to the soil through litter, playing an important role as sink of this element. Soil microarthropods are keys to understanding the soil ecosystem, and for such purpose were characterized by the soil fauna of two Units of Forest Conservation of the state of the Rio de Janeiro, inwhich one of the areas suffer quite interference from petrochemicals and industrial anthropogenic activities and other area almost exempts of these perturbations. The results showed that soil and litter of the Atlantic Forest in Brazil tend to stock high mercury concentrations, which could affect the abundance and richness of soil fauna, endangering its biodiversity and thereby the functioning of ecosystems.

关键词： Biodiversity Litter Microarthropods Soil Trace-element

Stellar Structure Model in the Post-Newtonian Approximation

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Research in Astronomy and Astrophysics 2022年第12期22卷 232-238页

作者： Gilberto M.Kremer departamento de Física Universidade Federal do ParanáCuritiba 81531Brazil

In this work the influence of the post-Newtonian corrections to the equations of stellar structure are *** post-Newtonian Lane-Emden equation follows from the corresponding momentum density balance *** a polytropic equation of state the solutions of the Lane-Emden equations in the Newtonian and post-Newtonian theories are determined and the physical quantities for the Sun,the white dwarf Sirius B and neutron stars with masses M■1.4 M_(⊙),1.8 M_(⊙)and 2.0 M_(⊙)are *** is shown that the post-Newtonian corrections to the fields of mass density,pressure and temperature are negligible for the Sun and Sirius B,but for stars with strong fields the differences become *** the neutron stars analyzed here the central pressure and the central temperature which follow from the post-Newtonian Lane-Emden equation are about fifty to sixty percent greater than those of the Newtonian theory and the central mass density is about three to four percent smaller.

关键词： stars:neutron stars:fundamental parameters hydrodynamics

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

Generalized Jackiw-Teitelboim gravity in presence of Block brane-like models

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Chinese Physics C 2022年第12期46卷 258-270页

作者： I.Andrade D.Bazeia A.S.Lobão Jr. R.Menezes departamento de Física Universidade Federal da Paraíba58051-970 João PessoaPBBrazil Escola Técnica de Saúde de Cajazeiras Universidade Federal de Campina Grande58900-000 CajazeirasPBBrazil departamento de Ciências Exatas Universidade Federal da Paraíba58297-000 Rio TintoPBBrazil

We investigate generalized Jackiw-Teitelboim gravity,coupling the dilaton field with two scalar matter *** obtain the equations of motion for the fields and investigate a linear perturbation of the solutions in *** study two specific situations that allow for analytic solutions with topological behavior and check how the dilaton field,the warp factor and the Ricci scalar *** particular,we show how the parameters can be used to modify the structure of the ***,the perturbations are,in general,described by intricate coupled differential equations,but in some specific cases,we can construct the corresponding zero modes analytically.

关键词： Dilaton 2D gravity Multifield

Bactericidal activity of hydrogel beads based on N,N,N-trimethyl chitosan/alginate complexes loaded with silver nanoparticles

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Chinese Chemical Letters 2015年第9期26卷 1129-1132页

作者： Alessandro F.Martins Johny P.Monteiro Elton G.Bonaf Adriana P.Gerola Cleiser T.P.Silva Emerson M.Girotto Adley F.Rubira Edvani C.Muniz departamento de Quimica Universidade Tecnologica Federal do Parana(UTFPR) Grupo de Materials Polimericos e Compositos Universidade Estadual de Maringa(UEM)

Polysaccharide-based composite materials（beads） containing silver nanoparticles（AgNPs） were successfully *** beads acted as an efficient vehicle for Ag＊ *** promoted the AgNPs protection and inhibited their *** assays showed that the beads/AgNPs concentration can be modulated to deliver an amount of Ag＊ necessary for kill Escherichia coli cells.

关键词： N N N-Trimethyl chitosan Alginate Silver nanoparticles Antimicrobial activity delivery

Sao Francisco-Congo Craton break-up delimited by U-Pb-Hf isotopes and trace-elements of zircon from metasediments of the Aracuaí Belt

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Geoscience Frontiers 2019年第2期10卷 611-628页

作者： Mathias Schannor Cristiano Lana Marco A.Fonseca Applied Isotope Research Group Department of GeologyUniversidade Federal de Ouro Preto

detrital zircon U-Pb geochronology combined with Hf isotopic and trace element data from metasedimentary rocks of the Aracuai Belt in southeastern Brazil provide evidence for break-up of the Congo-Sao Francisco Craton. The U-Pb age spectra of detrital zircons from metasediments of the Rio Doce Group(RDG) range from 900-650 Ma and define a maximum depositional age of ca. 650 Ma. Zircon trace element and whole rock data constrain an oceanic island arc as source for the deposition setting of the protoliths to the metasediments. Zircon ε_(Hf)(t) values from these rocks are positive between +1 and +15, supporting previous evidence of a Neoproterozoic extensional phase and oceanic crust formation in a precursor basin to the Aracuai Belt. Recrystallization of detrital zircon at ca. 630 Ma is compatible with a regional metamorphic event associated with terrane accretion to the Paleoproterozoic basement after transition from an extensional to a convergent regime. The juvenile nature, age spectra and trace element composition recorded in detrital zircons of metasediments from the Aracuai Belt correspond with zircons from metasedimentary rocks and oceanic crust remnants of other orogenic belts to its south. This suggests that rifting and oceanic crust formation of the entire orogenic system, the so-called Mantiqueira Province, was contemporaneous, most likely related to the opening of a large ocean. It further indicates that the cratonic blocks involved in the orogenic evolution of the Mantiqueira Province were spatially connected as early as 900 Ma.

关键词： detrital zircon U-Pb geochronology Lu-Hf isotopes Trace elements Aracuaí Belt

Pathogenesis and clinical management of Helicobacter pylori gastric infection

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World Journal of Gastroenterology 2019年第37期25卷 5578-5589页

作者： Breno Bittencourt de Brito Filipe Ant?nio Fran?a da Silva Aline Silva Soares vinícius Afonso Pereira Maria Luísa Cordeiro Santos Mariana Miranda Sampaio Pedro Henrique Moreira Neves Fabrício Freire de Melo Instituto Multidisciplinar em Saúde Universidade Federal da Bahia

Helicobacter pylori(***)is a gram-negative bacterium that infects approximately 4.4 billion individuals ***,its prevalence varies among different geographic areas,and is influenced by several *** infection can be acquired by means of oral-oral or fecal-oral transmission,and the pathogen possesses various mechanisms that improve its capacity of mobility,adherence and manipulation of the gastric microenvironment,making possible the colonization of an organ with a highly acidic *** addition,*** presents a large variety of virulence factors that improve its pathogenicity,of which we highlight cytotoxin associated antigen A,vacuolating cytotoxin,duodenal ulcer promoting gene A protein,outer inflammatory protein and gamma-glutamyl *** host immune system,mainly by means of a Th1-polarized response,also plays a crucial role in the infection *** most ***-positive individuals remain asymptomatic,the infection predisposes the development of various clinical conditions as peptic ulcers,gastric adenocarcinomas and mucosa-associated lymphoid tissue *** and non-invasive diagnostic methods,each of them with their related advantages and limitations,have been applied in *** ***,bacterial resistance to antimicrobial therapy is a major challenge in the treatment of this infection,and new therapy alternatives are being tested to improve *** *** but not least,the development of effective vaccines against *** infection have been the aim of several research studies.

关键词： Helicobacter pylori virulence factors Immune response Antibiotics Vaccines

Teleportation of Entangled States through Divorce of Entangled Pair Mediated by a Weak Coherent Field in a High-Q Cavity

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Chinese Physics Letters 2008年第7期25卷 2488-2491页

作者： W. B. Cardoso N. G. de Almeida Instituto de Ffsica Universidade Federal de Goiaes 74.001-970 Goiaenia (GO) Brazil Nucleo de Pesquisas em Fisica Universidade Catoelica de Goids 74.605-080 Goiania (GO) Brazil

We propose a scheme to partially teleport an unknown entangled atomic state. A high-Q cavity, supporting one mode of a weak coherent state, is needed to accomplish this process. By partial teleportation we mean that teleportation will occur by changing one of the partners of the entangled state to be teleported. The entangled state to be teleported is composed by one pair of particles, we called this surprising characteristic of maintaining the entanglement, even when one of the particle of the entangled pair being teleported is changed, of divorce of entangled states.

关键词： UNKNOWN ATOMIC STATE deTERMINISTIC QUANTUM TELEPORTATION PODOLSKY-ROSEN CHANNELS SCHEME SUPERPOSITION OPERATIONS LIGHT

Complex Polynomial Vector Fields Having a Finitely Curved Orbit

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Acta Mathematica Sinica,English Series 2007年第12期23卷 2247-2252页

作者： B.SCDUA Instituto de Matemática C.P.68530Universidade Federal do Rio de Janeiro

The author proves that a non-singular polynomial vector field without invariant lines and having an entire finitely curved transcendent orbit on C^2 must be equivalent to a trivial vector field by a holomorphic change of coordinates. Other classification results are obtained for polynomial vector fields having a finitely curved orbit on C^2.

关键词： holomorphic foliation minimal immersion Huber-Osserman theorem

Worker laying in leafcutter ant Acromyrmex subterraneus brunneus （Formicidae, Attini）

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Insect Science 2007年第2期14卷 157-163页

作者： ROBERTO S. CAMARGO LUIZ C. FORTI JULIANE F. S. LOPES NEWTON C. NORONHA ANGELO L. T. OTTATI departamento de Producāo Vegetal FCA/UNESP Botucatu SP Campus Universitário Paulo VI Sāo Luis MA Brazil. Comportamento e Biologia Animal Instituto de Ciencias Biológicas Universidade Federal de Juiz de Fora Campus Universitário Martelos Juiz de Fora MG Campus Universitário Paulo VI Sāo Luis MA Brazil. departamento de Entomologia Fitopatologia e Zoologia Agricola Escola Superior de Agricultura 'Luiz de Queiroz' Universidade de Sao Paulo Piracicaba SP Campus Universitário Paulo VI Sāo Luis MA Brazil. departamento de Fitotecnia e Fitossanidade Universidade Estadual do Maranhāo Centro de Ciencias Agrenias Campus Universitário Paulo VI Sāo Luis MA Brazil.

We studied the process of offspring production in queenless colonies of Acromyrmex subterraneus brunneus, and particularly evaluated the ovary development of workers as a function of their age. For this, subcolonies were set up and evaluated at different periods of isolation from the queen （2, 4 and 6 months）, besides individually labeled age groups. The subcolonies were assessed according to offspring production and ovaries containing oocytes or not. The evaluations showed worker oviposition and development of males originating from worker-laid eggs. At 2 months＇ absence of the queen, eggs and larvae were found, with eggs in a higher proportion than larvae. After 4 months, the proportion of eggs had reduced while larvae had increased, and a pupa was found in one subcolony. At 6 months, besides a higher share of larvae, one pupa and one adult male were found. Dissection of workers revealed ovaries containing oocytes during the periods of evaluation. Only a group of medium-sized and large workers, 23.3%, 20.9% and 37.5% of the population from each period assessed in queenless subcolonies respectively, presented developed oocytes in the ovary. The same was observed in colonies with a queen, with 17.6%, 19.6% and 7.8% of the group of dissected workers from each time period, respectively. With respect to worker age, we observed by dissection of the ovary, that the greatest percentage of individuals with ovarioles containing oocytes occurred at 45 days （6 weeks） up to 90 days （12 weeks）. These results probably are associated with the workers reproduction and the laying of trophic and reproductive eggs in colonies with and without a queen; these eggs have distinct functions in each situation.

关键词： leafcutter ant queenless ant colonies reproduction conflict worker laying,worker reproduction