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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

Re-bleeding events in patients with obscure gastrointestinal bleeding after negative capsule endoscopy

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World Journal of Gastrointestinal Endoscopy 2015年第4期7卷 403-410页

作者： Pedro Magalhes-Costa Miguel Bispo Sofia Santos gilberto couto Leopoldo Matos Cristina Chagas Gastroen-terology Department Hospital Egas MonizCentro Hospitalar Lisboa Ocidental

AIM: To investigate long-term re-bleeding events after a negative capsule endoscopy in patients with obscure gastrointestinal bleeding(OGIB) and the risk factors associated with the ***: Patients referred to Hospital Egas Moniz(Lisboa, Portugal) between January 2006 and October 2012 with OGIB and a negative capsule endoscopy were retrospectively analyzed. The following study variables were included: demographic data, comorbidities, bleeding-related drug use, hemoglobin level, indication for capsule endoscopy, post procedure details, work-up and follow-up. Re-bleeding rates and associated factors were assessed using a Cox proportional hazard analysis. The Kaplan-Meier method was used to estimate the cumulative incidence of re-bleeding at 1, 3 and 5 years, and the differences between factors were ***: The study population consisted of 640 patients referred for OGIB investigation. Wireless capsule endoscopy was deemed negative in 113 patients(17.7%). A total of 64.6% of the population was female, and the median age was 69 years. The median follow-up was forty-eight months(interquartile range 24-60). Re-bleeding occurred in 27.4% of the cases. The median time to re-bleeding was fifteen months(interquartile range 2-33). In 22.6%(n = 7) of the population, small-bowel angiodysplasia was identified as the culprit lesion. A univariate analysis showed that age > 65 years old, chronic kidney disease, aortic stenosis, anticoagulant use and overt OGIB were risk factors for re-bleeding; however, on a multivariate analysis, there were no risk factors for re-bleeding. The cumulative risk of re-bleeding at 1, 3 and 5 years of follow-up was 12.9%, 25.6% and 31.5%, *** who presented with overt OGIB tended to rebleed sooner(median time for re-bleeding: 8.5 mo vs 22 mo).CONCLUSION: Patients with OGIB despite a negative capsule endoscopy have a significant re-bleeding risk; therefore, these patients require an extended follow-up strategy.

关键词： Capsule endoscopy Gastrointestinalhemorrhage Anemia Angiodysplasia 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.

Influence of physical-anatomical wood variables on charcoal physical-mechanical properties

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Journal of Forestry Research 2023年第2期34卷 531-538页

作者： Allan Motta couto Thiago Campos Monteiro Paulo Fernando Trugilho JoséTarcísio Lima JoséReinaldo Moreira da Silva Alfredo Napoli Diego Pierre de Almeida Department of Forestry Science State University of Mato Grosso do Sul–UEMSAv.Graziela Maciel BarrosoKm 12 Zona RuralAquidauanaMS 79200000Brazil Department of Forestry Engineering and Technology Federal University of Paraná–UFPRA V.Pref.Lothário Meissner 632Jardim BotânicoCuritibaPR 80210170Brazil Department of Forestry Science Federal UniversityLavras–UFLALavrasMG 37200000Brazil Département de Performance Des Systèmes de Production Et de Transformation Tropicaux Centre de Coopération Internationale em Recherche Agronomique pour le Développement–CIRADMontpellierFrance

This research assessed the relationship between wood physical-anatomical variables and charcoal physical-mechanical *** trees were harvested and mechanically processed into standard pieces for laboratory *** following variables were determined:wood density,fiber length and width,fiber lumen diameter and wall thickness,fiber wall fraction,and vessel *** charcoal was produced in a laboratory and gravimetric yield,relative density,and mechanical properties ***’s correlation coefficients,multivariate statistical analysis of canonical correlation,and principal component analysis were used to evaluate the relationship between wood and charcoal *** width was not significantly correlated with charcoal *** bulk density,hardness,and strength were positively correlated with wood density,fiber length,wall thickness,and wall *** properties were negatively correlated with fiber lumen diameter and vessel *** results will help identify the best wood with adequate physical-mechanical properties for industrial charcoal proces sing.

关键词： Biomass Density Energy Fiber Vessel

Brazilian payment for environmental services programs emphasize water-related services

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International Soil and Water Conservation Research 2023年第2期11卷 276-289页

作者： Ingrid Mamedes Angélica Guerra Dulce B.B.Rodrigues Letícia couto Garcia Raquel de Faria Godoi Paulo Tarso S.Oliveira Faculty of Engineering Architecture and Urbanism and GeographyFederal University of Mato Grosso do SulMS79070-900Brazil Programa de Pós-Graduaçāo em Ecologia e Conservaaçāo Universidade Federal de Mato Grosso do SulCampo GrandeBrazil Laboratorio de Ecologia da Intervenaçāo-LEl Instituto de BiociênciasUniversidade Federal de Mato Grosso do SulCampo GrandeBrazil Department of Hydraulics and Sanitary Engineering Sao Carlos School of EngineeringUniversity of Sao PauloSao CarlosSPBrazil

Based on"user pays"and"provider gets"principles,the Payment for Environmental Services(PES)consists of providing economic incentives or compensation for land users who adopt activities that promote ecosystem *** PES initiatives have grown rapidly in Brazil over the last few decades,however,studies that address the panorama of these programs in the country are still scarce,regional,or ***,we investigate the PES overview in Brazil through interviews and an extensive literature *** found in total 80 PES programs implemented in Brazil,of which 14 were *** pro-grams are poorly distributed across the country,mostly concentrated in the Atlantic Forest(56.25%)and Savanna(36.25%)biomes,in Southeastern *** majority of programs primarily prioritize improving water quality and ***,reforestation,protection of native vegetation,and soil and water conservation are their main proposed *** positive impacts of Brazil's PES experi-ences are evident;while the lack of transparency and monitoring,and poor spatial and financial dis-tribution are still major *** conclude that if correctly implemented,PES schemes offer a path to reconcile environmental conservation with agricultural production in Brazil.

关键词： Conservation funding Ecological restoration Environmental compliance Public policy Soil and water conservation

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：燃烧室雾化理论液体膜

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：计算机流体动力学流体力学模型流化床气化零维模型气化模型 CFD模型结合动力学数值模拟

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

A grain-size correction for metal pollution indexes in river sediments

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International Journal of Sediment Research 2021年第3期36卷 362-372页

作者： Thomas Vincent Gloaguen Paula Núbia Soares Dalto Motta Carolina Fonseca couto Federal University of Reconcavo of Bahia Federal University of Minas Gerais

According to the List of Hazardous Substances of the Agency of the Toxic Substances and Disease Registry(ATSDR 2017), some metallic elements such as Pb or Cd are still considered as the most polluting elements in the world. These elements accumulate in sediments, and there are various methods available that differentiate lithogenic sources from anthropogenic sources. For that, the natural geochemical background is required, however, its definition is far from unanimous: it can be a global or local value,single or statistically estimated value, depending on the studies. Our study is focused on the Subae River in the state of Bahia, Northeastern Brazil, which was historically contaminated by lead metallurgy. The river sediments were sampled at 21 locations: one at the discharge point of the plant’s rainwater basin,ten upstream, and ten downstream. The total contents of Fe, Ti, Mn, Pb, Zn, Cu, Cr, particle-size distribution, and organic matter were analyzed. The conventional geochemical indexes, i.e., the pollution degree(m Cd), pollution load index, and enrichment factor indicated contamination by Zn, Pb, Cr, and ***, a new enrichment factor is introduced, assuming that the sediments come from erosion of soils in the watershed. After obtaining the natural concentrations of metals in the clay, silt, and sand fractions of uncontaminated reference soils, we corrected the pollution indexes by calculating a new individual background in each sediment sample, according to its grain size distribution. This new approach provided more precise indexes in the assessment of sediment pollution, by highlighting higher contamination of Zn and Pb(around 50%) and at the same time the absence of Cr and Cu contamination, two metals not involved with the metallurgical activity.

关键词： Enrichment factor Estimated background Particle-size distribution

The“microwave oven”practice in Brazil

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Forensic Sciences Research 2022年第4期7卷 628-632页

作者： Yara Vieira Lemos Luciene Menrique Corradi Melina Calmon Silva Lorena de Oliveira couto Giovanna Hooper Bittencourt Alexander Santos Dionísio Adriana Zatti Lima Márcio Alberto Cardoso Eugénia Cunha Forensic Anthropology Laboratory Medico-Legal Institute AndréRoquette in Belo HorizonteMinas GeraisBrazil Medical Sciences Faculty of Minas Gerais Minas GeraisBrazil Brazilian Association of Forensic Anthropology(ABRAF) BrasíliaBrazil.

This article presents a forensic case of an unusual illegal cremation of a person using a process colloquially known as the“microwave oven”practice in *** microwave process involves two actions:placing the victim in a tire stack and then setting the structure on fire using flammable substances to accelerate the *** practice,identified as“necklacing”,has also been reported in other countries such as South *** report presents a case of microwave oven cremation of a body found in a rural area of Minas Gerais,*** forensic work helped determine the biological profile and identity of the victim using radiological *** the microwave oven cremation practice is rare,it can impose challenges for ***,fully understanding this practice can be helpful to the academic and forensic communities.

关键词： Forensic sciences carbonization cremation homicide human identification