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International audience; Context. η Car is one of the most intriguing luminous blue variables in the Galaxy. Observations and models of the X-ray, ultraviolet, optical, and infrared emission suggest a central binary in a highly eccentric orbit with a 5.54 yr period residing in its core. 2D and 3D radiative transfer and hydrodynamic simulations predict a primary with a dense and slow stellar wind that interacts with the faster and lower density wind of the secondary. The wind-wind collision scenario suggests that the secondary’s wind penetrates the primary’s wind creating a low-density cavity in it, with dense walls where the two winds interact. However, the morphology of the cavity and its physical properties are not yet fully constrained.Aims. We aim to trace the inner ∼5–50 au structure of η Car’s wind-wind interaction, as seen through Brγ and, for the first time, through the He I 2s-2p line.Methods. We have used spectro-interferometric observations with the K-band beam-combiner GRAVITY at the VLTI. The analyses of the data include (i) parametrical model-fitting to the interferometric observables, (ii) a CMFGEN model of the source’s spectrum, and (iii) interferometric image reconstruction.Results. Our geometrical modeling of the continuum data allows us to estimate its FWHM angular size close to 2 mas and an elongation ratio ϵ = 1.06 ± 0.05 over a PA = 130° ± 20°. Our CMFGEN modeling of the spectrum helped us to confirm that the role of the secondary should be taken into account to properly reproduce the observed Brγ and He I lines. Chromatic images across the Brγ line reveal a southeast arc-like feature, possibly associated to the hot post-shocked winds flowing along the cavity wall. The images of the He I 2s-2p line served to constrain the 20 mas (∼50 au) structure of the line-emitting region. The observed morphology of He I suggests that the secondary is responsible for the ionized material that produces the line profile. Both the Brγ and the He I 2s-2p maps are consistent with previous hydrodynamical models of the colliding wind scenario. Future dedicated simulations together with an extensive interferometric campaign are necessary to refine our constraints on the wind and stellar parameters of the binary, which finally will help us predict the evolutionary path of η Car.; Contexte : η Car est une des étoiles brillantes bleues variables les plus intrigante de notre galaxie. Les observations et les modèles des émissions X, UV et optique et IR suggèrent qu'une étoile binaire avec une orbite fortement excentrique de période 5,54 ans réside au centre de son coeur. Les simulations hydrodynamiques et de transfert radiatif 2D et 3D prédisent la présence d'une étoile primaire avec vent stellaire dense et lent, qui interagit avec le vent de densité moindre et plus rapide de l'étoile secondaire. Ce scénario de collision vent-vent suggère que le vent de l'étoile secondaire pénètre dans le vent de l'étoile primaire, créant dans ce dernier une cavité de faible densité, avec des murs denses où les deux vents interagissent. Cependant, la morphologie de cette cavité et ses propriétés physiques ne sont pas encore pleinement contraints.Objectifs. Nous visons à déterminer la structure interne de l’interaction vent-vent de Car dans une zone allant de 5 à 50 Unités Astronomiques, telle que vue à travers Br γ et, pour la première fois, à travers la transition 2s-2p de He I.Méthodes : Nous avons utilisé des observations spectro-interférométriques du combineur de faisceaux en bande K de GRAVITY au VLTI. Les analyses des données comprennent: (i) un ajustement de modèle paramétrique aux observables interférométriques, (ii) un modèle CMFGEN du spectre de la source, et (iii) des reconstructions d'image interférométriques.Résultats : Notre modélisation géométrique des données du continuum nous permet d'estimer sa taille angulaire FWHM proche de 2 mas et son coefficient d'allongement de 1,06 ± 0,05 sur un PA = 130° ± 20°. Notre modélisation CMFGEN du spectre nous a permis de confirmer que le rôle de l'étoile secondaire devrait être pris en compte pour reproduire correctement les émissions Br γ et He I observées. Les images spectrales dans la bande Br γ révèle une caractéristique semblable à un arc au sud-est, peut-être associé aux vents chauds post-choc circulant le long du mur de la cavité. Les images dans la bande He I 2s-2p ont servi à contraindre la structure de la région d'émission de la transition, avec une résolution de 20 millisecondes d'arc (50 UA). La morphologie observée de He I suggère que l'étoile secondaire est responsable de l'ionisationproduisant le profil de raie. Les deux images (en Br γ et He I 2s-2p) sont compatibles avec les modèles hydrodynamiques précédents du scénario de vent en collision. De futures simulations dédiées ainsi qu’une vaste campagne interférométrique sont nécessaires pour affiner nos contraintes sur le vent et les paramètres stellaires de la binaire, ce qui nous aidera enfin à prédire le chemin évolutif de η Car.

Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2022-12-08T16:25:18Z No. of bitstreams: 1 2020 - Francisco Janio Cortez?o Barros.pdf: 2298705 bytes, checksum: 82282f13ed715db87f38719a98907cdc (MD5) Made available in DSpace on 2022-12-08T16:25:19Z (GMT). No. of bitstreams: 1 2020 - Francisco Janio Cortez?o Barros.pdf: 2298705 bytes, checksum: 82282f13ed715db87f38719a98907cdc (MD5) Previous issue date: 2020-07-08 CAPES - Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior Taking the elaboration of a contextualized pedagogical policy and manager of transformative actions that allows students to undertake for life, local development (endogenous) will have great chances to be potentiated, as the subject's empowerment in the field is one of the challenges of education. To make such an approach viable, it is essential to develop principles that allow students to have practical insertion from theoretical contributions consistent with their reality. To this end, the Instituto Federal de Educa??o, Ci?ncia e Tecnologia do Amazonas - IFAM, Campus Coari, municipality of the state of Amazonas, has placed in its curriculum three technical courses to meet the need of the Primary Sector of the municipality, which are as follows: Technical in Agriculture, Agricultural Technician and Fishery Technician. In order to analyze the effectiveness of this proposal, this research seeks to dialogue with some aspects of the theory about regional and local development in order to ponder the importance that these courses have for the local community of students. The methodology used was the descriptive research whose starting point was the analysis of the students' opinion, as well as the bibliographical research about the professional formation in the rural area and the theory about the regional and local development. The research contextualizes the practical teaching experience from the rural reality of micro entrepreneurs trained by the courses offered by IFAM Campus Coari, AM. Finally, research indicates that students prepared to work in the primary sector expect teachers and the course to respond more effectively to the process of training for management and rural entrepreneurship, by synthesizing the theoretical and practical aspects more emphatically. Tomando-se a elabora??o de uma pol?tica pedag?gica contextualizada e gerenciadora de a??es transformadoras que permitam aos alunos empreenderem para a vida, o desenvolvimento local (end?geno) a escola ter? grandes chances de ser potencializada, pois o fortalecimento do sujeito no campo ? um dos desafios da educa??o no campo. Para tornar vi?vel tal abordagem, ? fundamental a elabora??o de princ?pios que permitam aos alunos terem inser??o pr?tica desde aportes te?ricos consequentes com a sua realidade. Para tanto, o Instituto Federal de Educa??o, Ci?ncia e Tecnologia do Amazonas ? IFAM, Campus Coari, munic?pio do Estado do Amazonas, tem colocado em sua matriz curricular tr?s cursos t?cnicos para suprir a necessidade do Setor Prim?rio do munic?pio, que s?o os seguintes: T?cnico em Agricultura, T?cnico em Agropecu?ria e T?cnico em Recursos Pesqueiros. No intuito de analisar a efetividade desta proposta, a presente pesquisa busca dialogar com alguns aspectos da teoria acerca do desenvolvendo regional e local no sentido de ponderar a import?ncia que estes cursos t?m para a comunidade local de alunos. A metodologia usada foi a pesquisa descritiva cujo ponto de partida foi a an?lise da opini?o dos alunos, bem como a pesquisa bibliogr?fica a respeito da forma??o profissional no meio rural e da teoria acerca do desenvolvimento regional e local. A pesquisa contextualiza a experi?ncia pr?tica docente a partir da realidade rural dos microempreendedores capacitados pelos cursos oferecidos pelo IFAM Campus Coari, AM. Por fim, a pesquisa indica que os alunos preparados para atuar no setor prim?rio esperam que os professores e o curso respondam de forma mais eficaz ao processo de capacita??o ? gest?o e ao empreendedorismo rural, sintetizando de maneira mais enf?tica os aspectos te?ricos e pr?ticos.

Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2021-09-10T12:16:28Z No. of bitstreams: 1 2018 - William J?natas Vidal Coutinho.pdf: 1975916 bytes, checksum: bee03c21e09b1a91afaa127f6f29afe2 (MD5) Made available in DSpace on 2021-09-10T12:16:28Z (GMT). No. of bitstreams: 1 2018 - William J?natas Vidal Coutinho.pdf: 1975916 bytes, checksum: bee03c21e09b1a91afaa127f6f29afe2 (MD5) Previous issue date: 2018-12-13 Working the inclusion of deaf people in school amid the linguistic differences is a current issue. The educational strategies to be adopted require that attention is given to the different deaf identities and their specificities that affect the student's educational needs. The education of the deaf is affected by multiple factors such as the organization of the educational system in which they are inserted, the presence of professionals working education in a language comprehensible to the learner and the acceptance of that language by the deaf, subject who constructs an identity and culture in social interaction. This article outlines deaf cultures, the different deaf identities and the process of constitution and transformation of these identities in the educational context from specific cases present in the schooling of deaf people in the Federal Institute of Roraima. The qualitative study made use of semi-structured interview, an analysis of what was said by deaf students in the Federal Institute of Roraima and a field diary where observation of deaf students were registered. The instruments also focused on different views of interviewed deaf subjects about their educational process in public education. The material in this research makes it clear that the challenges to an inclusive practice can be minimized when we look at the differences seeking to define methodological strategies of work and educational interaction. That work needs to be carried together by interpreter, teacher, school community and family members of the deaf. Thus, educational results are increased by taking into account the student's identity experience. The researcher's experience working in the classroom as a Libras (BSL) interpreter at the Federal Institute of Roraima was also taken into account in the considerations. We found that the process of formation of identities and cultural identification are also inherent in the school, among other spaces. Interpreter and teacher need to know these identities and pay attention to the cultural specifics of the deaf student in their daily practice thus taking into account the specificities of the student Trabalhar a inclus?o de pessoas surdas na escola meio a diferen?a lingu?stica ? uma quest?o atual. As estrat?gias educacionais a serem adotadas exigem que seja dada aten??o ?s diferentes identidades surdas e suas especificidades que afetam as necessidades educacionais do aluno. A educa??o de surdos ? afetada por m?ltiplos fatores como a organiza??o do sistema educacional em que est?o inseridos, a presen?a de profissionais trabalhando a educa??o em l?ngua compreens?vel para o educando e a aceita??o dessa l?ngua pelo sujeito que constr?i uma identidade e cultura em intera??o social. Esta pesquisa explana sobre culturas surdas, as diferentes identidades surdas e o processo de forma??o e transforma??o dessas identidades no contexto educacional a partir do estudo de arranjos discursivos de alguns casos espec?ficos presentes na escolariza??o de surdos no Instituto Federal de Roraima. A abordagem qualitativa desta pesquisa fez uso de entrevista semiestruturada, depoimentos, an?lises das falas de todos os alunos surdos inseridos no Instituto Federal de Roraima e um di?rio de campo em que fizemos registros de entrevistas e observa??es do cotidiano escolar dos alunos surdos. Esses instrumentos abordaram as diferentes vis?es dos sujeitos surdos entrevistados sobre seu processo educacional dentro da escola. A an?lise corroborou para mostrar que os desafios da pr?tica pedag?gica com o p?blico surdo podem ser minimizados ao olharmos para as diferen?as entre eles buscando definir estrat?gias metodol?gicas particulares/inclusivas dentro da escola como um todo em que int?rprete, professor e outros membros da comunidade escolar participam de um trabalho inclusivo e colaborativo. Assim, constatamos que o processo de forma??o de identidades e identifica??o cultural por meio das Libras e outros sinais espec?ficos dos alunos surdos do Instituto Federal de Roraima, dentre outros espa?os, ? inerente a escola, espa?o no qual os agentes escolares necessitam conhecer essas identidades e dar aten??o ?s especificidades culturais do aluno surdo levando em conta que cada aluno surdo ? ?nico