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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

On the Singular Effects in the Relativistic Landau Levels in Graphene with a Disclination

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Communications in Theoretical Physics 2018年第12期69卷 817-822页

作者： Rosinildo F.do Nascimento Diego Cogollo Edilberto O.Silva Moisés Rojas Cleverson Filgueiras Instituto de Fisica Universidade Federal de UberlandiaUberlandiaMGBrasil Unidade Academica de Fisica Universidade Federal de Campina GrandePOB 1007158109-970Campina Grande-PB Brazil Departamento de Fisica Universidade Federal do Maranhao65085-580Sao Luis-MABrazil Departamento de Fisica Universidade Federal de LavrasCaixa Postal 303737200-000Lavras-MGBrazil

The effect of a pseudo Aharonov-Bohm(AB) magnetic field generated by a disclination on a two-dimensional electron gas in graphene is addressed in the continuum limit within the geometric approach. The influence of the coupling between the spinor fields and the singular conical curvature is investigated, which shows that singularities have pronounced impact in the Hall conductivity. Moreover, the degeneracy related to the Dirac valleys is broken for negative values of the angular momentum quantum numbers, ?, including ? ≡ 0. In this case, a Hall plateau develops at the null filling factor. Obtaining the Hall conductivity by summing over the positive and the negative ?′s, the null Landau level is recovered and the plateau at the null filling factor disappears. In any case, the standard plateaus, which are seen in a flat graphene are not obtained with these curvature and singular effects.

关键词： Landau Levels Hall conductivity Graphene Elastic deformations

Utilization of Acai Berry Residual Biomass for Extraction of Lignocellulosic Byproducts

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Journal of Bioresources and Bioproducts 2021年第4期6卷 323-337页

作者： Lamia Zuniga Linan Anne C.Mendonça Cidreira Cláudia Quintino da Rocha Fabrícia Farias de Menezes George J de Moraes Rocha Antônio E Macedo Paiva Departamento de Engenharia Química Universidade Federal do Maranhao(UFMA)Av.dos Portugueses 1966Bacanga-CEP65080-805Sao Luís-MABrazil Departamento de Química Universidade Federal do Maranhao(UFMA)Av.dos Portugueses 1966Bacanga-CEP65080-805Sao Luís-MABrazil Brazilian Center for Research in Energy and Materials(CNPEM)and Brazilian Biorenewables National Laboratory(LNBR) Giuseppe Máximo Scolfaro 10.000Guará-CEP13083-100 Campinas-SPBrazil Departamento de Mecânica e Materiais(DMM) Instituto Federal de EducaçãoCiência e Tecnologia do maranhão(IFMA)São Luís-MABrazil

According to the National Company of Supplying(CONAB)in 2017 alone,the national production of acai pulp reached 219855 t,equating to 180 million dollar(USD).Almost 85%of the weight of fruit is constituted by residual biomass,even though researches have highlighted important applications for this biomass,most of it is discarded as organic ***,it is relevant to envisage in-depth studies about how to use these residues,particularly regarding the environmental impact of its target *** cellulose(CNC)and lignin are organic derivatives obtained through the physical-chemical treatment of lignocellulosic *** are abundant and currently considered as biopolymers because of their structural characteristics and their diverse applications in food and the medical *** work presents the mass yields achieved and the physical-chemical characteristics of the lignocellulosic derivatives extracted from the fiber of the acai berry.A statistical design was used to define the influence of process variables as temperature,reaction time and fiber size on the yield of these byproducts.A maximum yield close to 64%of type I CNC,with 45%of crystallinity degree was achieved at the minimum condition of temperature and fiber ***,through rheological analysis,it was possible to predict the nanocrystal aspect ratios,ranging from 71 to *** extracted lignin was rich in methoxy groups,p-coumaryl alcohol and p-coumaric acid,and its structural unit’s low state of aggregation can be an indication of low molecular weight,which envisions an appropriate use for this lignin to produce commodity chemicals.

关键词： Acai berry Residual biomass Cellulose nanocrystal(CNC) Lignin rheological characterization Physical-chemical characterization

Estimation of Genetic Parameters of Turiacu Pineapple Clones and Genetic Correlation between Traits

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Agricultural Sciences 2017年第11期8卷 1253-1262页

作者： Guilherme Barbosa Abreu Marcos Miranda Toledo Marcelo Mattos Cavallari Jose Ribamar Gusmao Araujo Antonia Alice Costa Rodrigues Luiz Gustavo de Lima Melo Augusto Cesar Vieira Neves Junior Embrapa Cocais(CPACP) Sao LuisBrazil Embrapa Pecuária Sudeste(CPPSE) Sao CarlosBrazil Universidade Estadual do Maranhao(UEMA) Sao LuisBrazil Universidade Federal Rural de Pernambuco(UFRPE) RecifeBrazil

This study aimed to estimate genetic parameters of Turiaçu pineapple clones using mixed models;and estimate genetic correlation coefficient between traits, to provide important information to breeding programs. For this, 19 pineapple plants were visually selected and its slips were collected and planted in a single environment and nine traits were evaluated. The genetic parameters of most evaluated traits presented significant differences between the 19 clones. Some traits, such as Fusarium wilt resistance, showed high magnitudes of heritability. Clones did not differ in relation to total titratable acidity (TTA) and total soluble solids (TSS). However, these traits, which have implications to fruit quality, showed to be negatively correlated to fruit mass (-0.46 and -0.67). The results indicate that the population of Turiaçu pineapple is suitable for selection, especially for Fusarium wilt resistance. Also, Turiaçu clones can be used in breeding programs of pineapple.

关键词： Quantitative Genetics Plant Breeding Ananas comosus

Measuring disturbance at swift breeding colonies due to the visual aspects of a drone:a quasi-experiment study

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Current Zoology 2021年第2期67卷 157-163页

作者： Geison P.MESQUITA JoséD.RODRÍGUEZ-TEIJEIRO Serge A.WICH Margarita MULERO-PÁZMÁNY Department of Animal Biology Plant Biology and EcologyFaculty of BioscienceAutonomous University of BarcelonaBarcelona 08193Spain Institut de Recerca de la Biodiversitat University of BarcelonaBarcelona 08193Spain Department of Evolutionary Biology Ecology and Environmental SciencesFaculty of BiologyBiodiversity Research Institute(IRBio)University of BarcelonaBarcelona 08193Spain School of Biological and Environmental Sciences Liverpool John Moores UniversityLiverpool L35UGUK Institute for Biodiversity and Ecosystem Dynamics University of AmsterdamAmsterdam 1012 WXThe Netherlands

There is a growing body of research indicating that drones can disturb ***,it is usu-ally unclear whether the disturbance is due to visual or auditory ***,we examined the effect of drone flights on the behavior of great dusky swifts Cypseloides senex and white collared swifts Streptoprocne zonaris in 2 breeding sites where drone noise was obscured by environmental noise from waterfalls and any disturbance must be largely *** performed 12 experimental flights with a multirotor drone at different vertical,horizontal,and diagonal distances from the *** all flights,17%caused50 m the disturbance percentage does not exceed 20%,at60%.We recommend that flights with a multirotor drone during the breeding period should be con-ducted at a distance of>50 m and that recreational flights should be discouraged or conducted at larger distances(e.g.100 m)in nesting birds areas such as waterfalls,canyons,and caves.

关键词： Cypseloides senex disturbance drones multirotors Streptoprocne zonaris unmanned aircraft systems

Effect of applying a calcined kaolin-based particle film on the photosynthetic capacity and growth of young eucalyptus plants

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Journal of Forestry Research 2021年第6期32卷 2473-2484页

作者： Diego Pereira Santos Mauriana da Rocha Sobrinho Maria de Fatima de Castro Oliveira Niedja Bezerra Costa Tiago Massi Ferraz Fabricio de Oliveira Reis Heder Braum Eliemar Campostrini Fabio Afonso Mazzei Moura de Assis Figueiredo Graduate Program in Agriculture and Environment State University of MaranhaoPraca Goncalves Diass/nCentroBalsasMA 65800-000Brazil Graduate Program in Agroecology State University of MaranhaoAv.Lourenco Vieira da Silva1000Jardim Sao CristovaoSao LuisMA 65055-310Brazil Graduate Program in Agronomy Campus SamambaiaEscola de AgronomiaFederal University of GoiasAv.Esperanca s/nGoianiaGO 74690-900Brazil State University of Maranhao Av.Lourenco Vieira da Silva1000Jardim Sao CristovaoSao LuisMA 65055-310Brazil Northern Rio de Janeiro State University Av.Alberto Lamego2000Campos dos GoytacazesRJ 28013-602Brazil

In scenarios of climatic change when increased global temperatures can be expected,it is essential to search for technologies that favor sapling survival and growth after planting and increase yield in the ***-based particle films(KBPF)have been applied as barriers against the deleterious effects of high levels of solar *** objective of the present study was to assess the effects of applying purified calcined kaolin-based particle film to young eucalyptus *** treatments were carried out:0%(just water),3%,5%,7%,and 10%calcined kaolin applied to the adaxial part of the leaves.A complete randomized block design was used with five treatments and ten *** plants were assessed for height,diameter at ground level,gas exchanges(net photosynthetic CO_(2) assimilation,stomatal conductance and transpiration),instantaneous(WUE)and intrinsic water use efficiency(IWUE),chlorophyll a fluorescence(maximum quantum yield of photosystem II(PSII)(Fv/Fm),concentration of active reaction centers in relation to the quantity of photons absorbed(RC/ABS)and the maximum ratio of quantum yields of photochemical and concurrent non-photochemical processes in PSII(Fv/F0),SPAD reading and leaf *** 3%KBPF concentration showed the best responses in biometric assessments 80 days after planting(DAP)and were corroborated by the responses of the leaf,stem and shoot dry matter production as a *** leaf ontogeny assessments showed positive responses following KBPF application when considering leaf development,with 7%KBPF concentration resulting in the highest mean *** mean specific leaf mass had negative response to high KBPF *** 60 DAP,the gas exchange variables during both assessment periods declined with an increase in KBPF *** differences as a result of KBPF applications were found only at the start of the assessments(34 DAP)for both WUE and for ***‘greenness’(SPAD reading)at 47 days showed a quadratic

关键词： Ecophysiology Photoprotection Yield Silviculture

Production and quality of eucalyptus mini-cuttings using kaolin-based particle films

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Journal of Forestry Research 2021年第3期32卷 953-965页

作者： Maria de Fátima de Castro Oliveira Diego Pereira Santos Karolline Sena Figueredo Fabrício de Oliveira Reis Tiago Massi Ferraz Heder Braun Eliemar Campostrini Fábio Afonso Mazzei Moura de Assis Figueiredo Graduate Program in Agriculture and Environment Centro de Estudos Superiores de BalsasState University of MaranhaoPraca Goncalves Diass/nCentro65800-000 BalsasMABrazil Enraize-E.M.Figueredo Ind.e Com.de Produtos Florestais Br 222Km 09Lote 52Margem Esquerda S/n:Chac.Belo HorizonteZona RualAcailandiaMABrazil Centro de Ciências Agrárias State University of MaranhaoAv.Lourenco Vieira da Silva1000Jardim Sao Cristovao65055-310 Sao LuísMABrazil CCTA Northern Rio de Janeiro State UniversityAv.Alberto Lamego200028013-602 Campos dos GoytacazesRJBrazil

Considering the expansion of forest plantations over the Brazilian territory and the imminent increase in air temperatures due to global warming,the search for technologies that ensure high levels of productivity and high quality plants in clonal nurseries is *** kaolin-based particle films(KBPF)has been used as a physical barrier to reduce the negative effects of excessive solar radiation and adverse *** effects of KBPF on production and physiological quality of eucalyptus mini-cuttings were evaluated during two different seasons.A randomized block design was used,consisting of five treatments and four *** concentrations(0,3%,5%,7%,and 10%)were tested here and six weekly replicates of each concentration was *** different kaolin concentrations and seasonal variations resulted in a quadratic response of the leaf SPAD reading during both daily evaluation *** applications resulted in a quadratic response of photochemical efficiency in the morning period,and an increasing specific leaf weight linear response,and during the dry season,the different kaolin concentrations resulted in a bud length quadratic *** results indicated that the kaolin application maintained the production and yield index statistically equal between weekly KBPF applications,improving photochemical efficiency,leaf thickness,SPAD reading,and bud *** use of KBPF could reduce the intervals between collections of mini-cuttings and increase nursery yields in environments that present high temperatures.

关键词： Photoprotector Ecophysiology Forestry Clonal propagation

Schistosoma mansoni Infection in Holochilus sciureus Shows Sex-Related Differences in Parasitological Patterns

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Open Journal of Animal Sciences 2019年第2期9卷 173-182页

作者： Guilherme Silva Miranda Joao Gustavo Mendes Rodrigues Maria Gabriela Sampaio Lira Ranielly Araujo Nogueira Gleycka Cristine Carvalho Gomes Neuton Silva-Souza Department of Parasitology Institute of Biological SciencesFederal University of Minas GeraisBelo HorizonteBrazil Teaching Department Federal Institute of MaranhaoSao Raimundo das MangabeirasBrazil Department of Pathology Centre for Biological and Health SciencesFederal University of MaranhaoSao LuisBrazil Department of Chemistry and Biology Laboratory of Human ParasitologyState University of MaranhaoSao LuisBrazil

Due to the different parasitological patterns found between sexes in human populations and in different biological models during Schistosoma mansoni infection, we proposed to investigate such differences using Holochilus sciureus rodent, besides confirming whether this rodent is suitable for experimental infections. In this sense, males and females of H. sciureus were infected with 200 cercariae from a human strain of S. mansoni. The number of eggs per gram of feces (epg) and the worms were quantified, besides histopathological analysis. Thus, it was shown that females have fewer epg, as well as a longer prepatent period. On the other hand, males had a lower recovery rate of adult worms. The histopathological analysis did not show differences between the sexes. Thus, we suggest that infection in H. sciureus females provides a favorable environment for the development of adult worms, despite impairing the parasite fecundity. In addition, H. sciureus may be an excellent biological model for S. mansoni experimental infections.

关键词： Biological Model Females Males Schistosomiasis Wild Reservoir

Hydrodynamics and suspended particulate matter retention in macrotidal estuaries located in Amazonia-semiarid interface(Northeastern-Brazil)

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International Journal of Sediment Research 2020年第4期35卷 417-429页

作者： Vinicius Henrique Maciel dos Santos Francisco Jose da Silva Dias Audalio Rebelo Torres Romulo Araujo Soares Lais Costa Terto Antonio Carlos Leal de Castro Ricardo Luvizotto Santos Marco Valerio Jansen Cutrim Laboratorio de Hidrodinamica Costeira Estuarina e de Aguas Interiores (LHiCEAI) Do Programa de Pos-Graduacao Em Oceanografia (PPGOceano) da Universidade Federal Do Maranhao (UFMA)Cidade Universitaria Dom Delgado Laboratorio de Ictiologia (LabIctio) da Universidade Federal Do Maranhao (UFMA) Cidade Universitaria Dom Delgado Laboratorio de Ecotoxicologia (LabEcotox) Do Programa de Pos-Graduacao Em Oceanografia (PPGOceano) da Universidade Federal Do Maranhao (UFMA) Cidade Universitaria Dom Delgado Laboratorio de Ficologia (LabFic) Do Programa de Pos-Graduacao Em Oceanografia (PPGOceano) da Universidade Federal Do Maranhao (UFMA) Cidade Universitaria Dom Delgado

The aim of the current study was to determine the nature of the seasonal variability of the Suspended Particulate Matter(SPM) fluxes from the drainage basin to the estuary in a macrotidal region(Northeastern Brazil),and the estuarine response to a seawater intrusion regarding sediment deposition,which will support the understanding of the global transport of materials at the continent-ocean *** structure data was acquired using a Conductivity,Temperature,and Depth(CTD) probe with a sampling frequency of 4 *** particulate material was measured by gravimetric measurements applied to exact filtered volume *** outflows were measured through the use of an Acoustic Doppler Current Profiler(ADCP) with frequency of 1.5 *** horizontal thermal and saline gradients varied from warmer and less saline waters(2014) to cooler and saline waters(2015).The gradient behavior when linked to volume transport and SPM flows,suggests a minimization of the fluvial flows in 2015,easing the advance of coastal water(CW) towards the inner estuary,leading to an inversion of the baroclinic pressure *** bottom saline front,generated by the entrance of coastal water masses,caused an increase in SPM concentrations due to increased fluid density,resuspension of previously deposited sediment,and erosion of *** concentrations of SPM indicate higher volume transport suggesting a hydraulic barrier due to the change/inversion of the baroclinic pressure gradient,resulting in water and material *** deposition was observed during neap tide,while during spring tide the material is resuspended,increasing the concentration,generating cycles of deposition and erosion during the neap-spring *** sediment in suspension that reach the estuary,even with low fluvial volume,stay in this environment forming new islands because of *** deposition rates or sediment cycling,if generated by the hydraulic barrier,may indicate that the flo

关键词： Brazilian Amazonia Materials discharges Macrotidal estuaries Freshwater percentage Residence time