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Journal of Semiconductors 2024年第9期45卷 28-35页

作者： Leonarde N.Rodrigues Wesley F.Inoch Marcos L.F.Gomes odilon D.D.couto Jr. Bráulio S.Archanjo Sukarno o.Ferreira Physics Department Federal University of ViçosaViçosa36570-900Minas GeraisBrazil Instituto de Física Gleb Wataghin Universidade Estadual de CampinasCampinas13083-859São PauloBrazil National Institute of Metrology Quality and Technology(Inmetro) Materials Metrology Division(DIMAT)Xerém2525-020Rio de JaneiroBrazil

This work shows that despite a lattice mismatch of almost 20%, CdMnTe/CdTe/CdMnTe heterostructures grown directly on Si(111) have surprisingly good optical emission properties. The investigated structures were grown by molecular beam epitaxy and characterized by scanning transmission electron microscopy, macro-and micro-photoluminescence. Low temperature macro-photoluminescence experiments indicate three emission bands which depend on the CdTe layer thickness and have different confinement characteristics. Temperature measurements reveal that the lower energy emission band (at 1.48 eV)is associated to defects and bound exciton states, while the main emission at 1.61 eV has a weak 2D character and the higher energy one at 1.71 eV has a well-defined (zero-dimensional, 0D) 0D nature. Micro-photoluminescence measurements show the existence of sharp and strongly circularly polarized (up to 40%) emission lines which can be related to the presence of Mn in the heterostructure. This result opens the possibility of producing photon sources with the typical spin control of the diluted magnetic semiconductors using the low-cost silicon technology.

关键词： CdMnTe/CdTe/CdMnTe heterostructure CdTe/CdMnTe quantum emitters quantum dot-like emission silicon(111)substrate

Localized-states quantum confinement induced by roughness in CdMnTe/CdTe heterostructures grown on Si(111) substrates

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Journal of Semiconductors 2024年第9期 34-42页

作者： Leonarde do Nascimento Rodrigues Wesley Fiorio lnoch Marcos L.F.Gomes odilon D.D.couto Jr. Bráulio S.Archanjo Sukarno olavo Ferreira Physics Department Federal University of Vi?osa Instituto de Física Gleb Wataghin Universidade Estadual de Campinas National Institute of Metrology Quality and Technology (Inmetro) Materials Metrology Division (DIMAT)

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Numerical Study on the Effect of Submerged Depth on the Horizontal Plate Wave Energy Converter

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China ocean Engineering 2014年第5期28卷 687-700页

作者： Flávio Medeiros SEIBT Eduardo Costa couto Elizaldo Domingues dos SANToS Liércio André ISoLDI Luiz alberto oliveira RoCHA Paulo roberto de Freitas TEIXEIRA Graduate Program of ocean Engineering Universidade Federal do Rio Grande96203-900 Rio Grande RS Brazil Mechanical Engineering Department Universidade Federal do Rio Grande do Sul90050-170 Porto Alegre RS Brazil

The growing search for clean and renewable energy sources has given rise to the studies of exploring sea wave energy. This paper is concerned with the numerical evaluation of the main operational principle of a submerged plate employed for the conversion of wave energy into electrical one. The numerical model used to solve the conservation equations of mass, momentum and transport of volume fraction is based on the finite volume method （FVM）. In order to tackle with the flow of mixture of air-water and its interaction with the device, the multiphase model volume of fluid （VoF） is employed. The purpose of this study is the evaluation of a numerical model for improvement of the knowledge about the submerged plate wave energy converter, as well as the investigation of the effect of the distance from the plate to the bottom of the sea （HP） on the performance of the converter. The simulations for several distances of the plate from the seabed show that the optimal efficiency is 64%, which is obtained for HP=0.53 m （88% of the depth）. This efficiency is 17% larger than that found in the worst case （HP=0.46 m, 77% of the depth）.

关键词： numerical simulation submerged plate wave energy conversion efficiency

Cloning and characterization of gene-resistant analogs(RGAs)involved in rust(Puccinia psidii) resistance in Eucalyptus grandis

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Journal of Forestry Research 2015年第3期26卷 711-718页

作者： Marcelo Luiz Laia Acelino couto alfenas Sergio Hermínio Brommonschenkel Shinitiro oda Eduardo José de Melo Inaê Mariêde Araú jo Silva Janaína Fernandes gonal.es Ariadne Marques Departamento de Engenharia Florestal Universidade Federal dos Vales do Jequitinhonha e Mucuri DiamantinaMinas Gerais 39100-000 Brazil Departamento de Fitopatologia Universidade Federal de Viosa Viosa Minas Gerais 36570-900 Brazil Suzano Bahia Sul Celulose S/A Suzano So Paulo Brazil

Disease-resistant genes play an important role in defending against a variety of pathogens and insect pests in plants. Most of the disease-resistant genes encode pro- teins with conserved leucine rich repeat and nucleotide binding site domains. In this study, we cloned and char- acterized gene-resistant analogs （RGAs） from Eucalyptus grandis using degenerate PCR, with primers specifically targeting these two domains. The amplified fragments were cloned into the pGEM-T vector and transformed into escherichia coli. Among the 90 clones obtained, 13 were sequenced and compared with each other and with previ- ously identified gene-resistant diseases. A BLASTX search in GenBank revealed high similarities among the con- served domains of these cloned genes with RGA genes. Some clones, however, showed no significant similarity with DNA sequences in GenBank. Southern blotting ana- lysis identified several polymorphic RFLP loci between distinct genotypes. However, none of them co-segregated with the Puccinia psidii Winter resistance gene 1 （Ppr1） in a population study.

关键词： Cloning Conserved domains RGAs Rust Eucalyptus

Screening of Type 2 Diabetes in the City of Belo Horizonte: Differences between Genders

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open Journal of Endocrine and Metabolic Diseases 2016年第4期6卷 141-149页

作者： braul.o roberto gonçal.es marinho couto Katiussia Brito Porto Fabiane de Freitas Sales Deborah Campos oliveira Larissa da Silva Pacheco Lídia Christina Guimarães Pereira Talita Santos de almeida Geiza Francielle Rodrigues de Souza Mariana Santos Romualdo Jaqueline Paulino de Souza Clara Araújo Veloso Instituto de Ciências Biológicas e da Saúde (ICBS) Centro Universitário de Belo Horizonte Brasil

Introduction: Diabetes mellitus is a major public health problem that carries a high social and economic burden. Its diagnosis is unknown in half of individuals who have the disease. The diagnosis of the risk factors should be done in the beginning, since changes in lifestyle and hyperglycemic correction may delay the appearance of the disease and its complications. In this context, screening has been considered an important tool for an early detection of diabetes in asymptomatic adults. objective: The objective is to track diabetes in people from BH, comparing genders. Patients and methods: People were interviewed with questions concerning the risk factors associated with the development of diabetes. According to the risk factors present, they were classified as non-diabetic [ND], pre-diabetic [PD] or diabetic [DM]. Statistical analyses were performed considering p ≤ 0.05 as significant. Results: 1264 individuals participated (5.5% DM, 6.5% PD, 88.0% ND). When grouped, PD and DM males were more prevalent than PD and DM females. Those in the DM group had higher blood pressure, age, glycaemia, number of past smokers, first-degree relatives with diabetes than either PD or ND. Both males and females in DM and PD groups had a higher waist circumference than did either ND males or females. ND men had a higher intake of fried food and smoked more in the past than ND women. Both ND and PD males had higher blood pressure than women from the same groups. Conclusion: Screening for diabetes is very important for an early diagnosis and to avoid future complications in patients. It’s possible to infer that women are more conscientious when it comes to taking care of themselves than men.

关键词： Diabetes Mellitus Screening Gender Risk Factors

optical neuroimaging of executive function impairments in food addiction

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Journal of Innovative optical Health Sciences 2022年第1期15卷 141-155页

作者： Tania alexandra couto Meng-Yun Wang Zhen Yuan Centre for Cognitive and Brain Sciences University of Macao TaipaMacao SARP.R.China Faculty of Health SciencesUniversity of MacaoTaipaMacao SARP.R.China

This study investigated the neural mechanisms located in the prefrontal cortex(PFC)involved in maintaining addictive-like eating ***,we aimed toll a gap in the existing literature and help clarify the food addiction(FA)cycle by inspecting the relationship between the executive control and psychopathology involved in the FA ***-three students recruited from the University of Macao participated in this *** investigated a hemodynamic response captured by NIRS recordings,activated during n-back,set-shifting,and go/nogo ***,we investigated the FA symptoms through the YFAS clinical inventory to better understand the relationship between hemodynamic response and clinical symptomatology in college ***,the hemodynamicndings conrm that altered cognitive control in executive function performance appears to be linked to addictive-like eating behaviors,which in turn conrms a circuit similarity between FA and the substance abuse population(SUD)as reported in previous fMRI ***,the psychologicalndings conrm the signicant association between the working memory decits and symptoms severity which suggest the role of self-control and regulation in limiting the storage resources as a potential trigger to develop overconsumption episodes in the FA *** highlight how disrupted self-control and regulation of craving and negative a®ect induced by mental imagery might shape and overload the working memory storage as a potential trigger to develop binge eating episodes to maintain the FA *** conclusion,the use of fNIRS in the context of eating disorders studies represents a valuable application,noninvasive,and patientfriendly tool,providing new insights into understanding the addiction cycle and treatment guidelines.

关键词： Food addiction executive functions working memory self-control optical neuroimaging.

osteoblasts are inherently programmed to repel sensory innervation

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Bone Research 2020年第3期8卷 343-355页

作者： Luis Leitao estrela Neto Francisco Conceicao Ana Monteiro Marina couto Cecilia Jal.es Daniela MSousa Meriem Lamghari Instituto de Investigacao e Inovacao em Saude(i3S) Universidade do Porto4200-135 PortoPortugal Instituto de Engenharia Biomedica(INEB) Universidade do Porto4200-135 PortoPortugal Instituto de Ciencias Biomedicas Abel Salazar(ICBAS) Universidade do Porto4050-313 PortoPortugal

Tissue innervation is a complex process controlled by the expression profile of signaling molecules secreted by tissue-resident cells that dictate the growth and guidance of *** innervation is part of the neuronal network of the bone tissue with a defined spatiotemporal occurrence during bone ***,the current understanding of the mechanisms regulating the map of sensory innervation in the bone tissue is still ***,we demonstrated that differentiation of human mesenchymal stem cells to osteoblasts leads to a marked impairment of their ability to promote axonal growth,evidenced under sensory neurons and osteoblastic-lineage cells *** mechanisms by which osteoblast lineage cells provide this nonpermissive environment for axons include paracrine-induced repulsion and loss of neurotrophic factors *** identified a drastic reduction of NGF and BDNF production and stimulation of Sema3A,Wnt4;and Shh expression culminating at late stage of oB *** noted a correlation between Shh expression profile,oB differentiation stages,and oB-mediated axonal *** of Shh activity and signaling reversed the repulsive action of osteoblasts on sensory ***,to strengthen our model,we localized the expression of Shh by osteoblasts in bone ***,our findings provide evidence that the signaling profile associated with osteoblast phenotype differentiating program can regulate the patterning of sensory innervation,and highlight osteoblast-derived Shh as an essential player in this cue-induced regulation.

关键词： stimulation innervation reversed

Generalized Liquid Film Atomization Theory

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Journal of Thermal Science 2000年第3期9卷 265-270页

作者： HeraldoS.couto DemetrioBastos－Netto INPE－NationalInstituteForspaceResearch Rod.PresidenteDutrakm40CachoeiraPaulistaSpBrazil12630－000 INPE－NationalInstituteForspaceResearch Rod.PresidenteDutrakm40CachoeiraPaulistaSpBrazil12630－00

The increase of the fuel burning area required by most practical combustion processes in order to guarantee the minimum energy density rate release for their start up and operation is normally achieved by the proper choice among several existing types of atomizers. For instance, impinging and multi-impinging jets atomizers are used in rocket combustion chambers, while splash-plate atomizers find their use when wall film cooling is required. Pressure swirl atomizers, either of simplex or duplex kind, along with Y-Jet or Spider Jet atomizers are used in industrial applications and in turbine combustion chambers. Notice, however, that all the types of atomizing devices listed above have one point in common: they are of pre-filming kind, i.e., before the droplet spray is generated, a liquid film is formed. This liquid film is broken into unstable ligaments which contract under the action of surface tension forming the droplets. once the film thickness is estimated, the droplets’ SMD (Sauter Mean Diameter) can be calculated, yielding a crucial parameter for the combustion chamber design. However, although this mechanism of droplet formation has been under study for several decades, most of the available results, are based upon experimental data, valid for a special type of atomizer under the given specific conditions only. This work offers a generalized theory for theoretically estimating the SMD of sprays generated by liquid pre-filming atomizers in general.

关键词： atomizers sprays droplets SMD.

Modeling of Fluidized Bed Gasification:Assessment of Zero-dimensional and CFD Approaches

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Journal of Thermal Science 2015年第4期24卷 378-385页

作者： Nuno couto Valter Silva Eliseu Monteiro P.S.D.Brito Abel Rouboa University of Tras-os-Montes and alto Douro INEGI/Faculty of Engineering University of Porto C3i-Interdisciplinary Center for Research and Innovation Polytechnic Institute of PortalegreLugar da AbadessaApartado 1487301-901PortalegrePortugal MEAM Department University of Pennsylvania

In modeling fluidized bed gasification experiments,equilibrium and CFD models are valuable *** existence of multi-dimensional effects inside the reactor vessel due to the kinetics of the process and the fluid dynamics phenomena could result in deviation from the zero-dimensional *** models integrating kinetics and hydrodynamics are being developed by using a computer fluid dynamics(CFD)*** objective of this investigation is to assess and compare the adequacy of zero-dimensional and CFD approaches in modeling fluidized bed gasification regarding a semi-industrial scale(numerical results are validated under experimental runs).Results show that the zero-dimensional model based on the approach of dual stage equilibrium performs reasonably well in adequately predicting the product gas composition at different operating conditions and for different feedstocks,although with quantitative ***,the discrepancy depends on the oxygen content of the oxidation agent and on the steam-to biomass ratio decreasing when these parameters *** models provide deeper information being able to estimate the syngas composition or other operating parameter at any point of space and *** of some quantitative discrepancy,the zero-dimensional modeling approach is deemed satisfactory from the viewpoint of the determining design conditions simulation.

关键词： Gasification CFD model Dual stage equilibrium model

Artificial equilibrium points and bi-impulsive maneuvers to observe 243 Ida

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Chinese Journal of Aeronautics 2021年第1期34卷 410-423页

作者： allan Kardec de alMEIDA Jr Geraldo Magela couto oLIVEIRA Antonio Fernando Bertachini de almeida PRADo National Institute for Space Research(INPE) Sao Jose dos Campos 12227-010Brazil Federal Center for Technological Education of Minas Gerais(CEFET-MG) Belo Horizonte 30421-169Brazil

In the restricted three-body problem,the traditional Lagrange points L1 and L2 are the only equilibrium points near the asteroid 243 *** thrust generated by a solar sail over a spacecraft enables the existence of new artificial equilibrium points,which depend on the position of the spacecraft with respect to the asteroid and the attitude of the solar *** equilibrium points generate new spots to observe the body from above or below the plane of *** points are very good observational locations due to their stationary *** work provides a preliminary analysis to observe Ida through the use of artificial equilibrium points as spots combined with transfer maneuvers between *** combination can be used to observe the asteroid from more different points of view in comparison to fixed *** analyses are made for a spacecraft equipped with a solar sail and capable of performing bi-impulsive *** solar radiation pressure is used both to maintain the equilibrium condition and to reduce the costs of the transfers and/or to create transfers with longer *** is a new aspect of the present research,because it combines the continuous thrust with initial and final small impulses,which are feasible for most of the spacecraft,because the magnitudes of the impulses are very *** combined maneuvers may reduce the transfer times of the maneuvers in most of the cases,compared with the maneuvers based only on continuous *** options involved in these transfers are shown,like to minimize the fuel spent(Dv)as a function of the transfer time or to extend the duration of the travel between the *** transfer times can be useful when observations are required during the transfers.

关键词： Artificial equilibrium points Astrodynamics orbital transfers Solar radiation pressure Solar sail