The dwarf planet Makemake as seen by X-Shooter

Makemake is one of the brightest known trans-Neptunian objects, as such, it has been widely observed. Nevertheless, its visibility to near-infrared spectrum has not been completely observed in medium-resolving power, aimed at studying in detail the absorption features of CH4 ice. In this paper, we present the spectrum of Makemake observed with X-Shooter at the Very Large Telescope (Chile). We analyse the detected features, measuring their location and depth. Furthermore, we compare Makemake’s spectrum with that of Eris, obtained with the same instrument and similar setup, to conclude that the bands of the CH4 ice in both objects show similar shifts.AAC acknowledges support from the Carlos Chagas Filho Foundation for Research Support of Rio de Janeiro State, FAPERJ (grant E26/203.186/2016), the Brazilian National Council for Scientific and Technological Development, CNPq (grants 304971/2016-2 and 401669/2016-5), and the Universidad de Alicante (contract UATALENTO18-02). ACSF and WMF acknowledge support from the Coordination for the Improvement of Higher Education Personnel, CAPES. NPA acknowledges support from Space Research Initiative/Florida Space Institute funds through the project ‘Digging-Up Ice Rocks in the Solar System’. JLO thanks support from grant AYA2017-89637-R and from the State Agency for Research of the Spanish, MCIU, through the ‘Center of Excellence Severo Ochoa’ award for the Instituto de Astrofísica de Andalucía (SEV-2017-0709)

Moderate D/H Ratios in Methane Ice on Eris and Makemake as Evidence of Hydrothermal or Metamorphic Processes in Their Interiors: Geochemical Analysis

Dwarf planets Eris and Makemake have surfaces bearing methane ice of unknown origin. D/H ratios were recently determined from James Webb Space Telescope (JWST) observations of Eris and Makemake (Grundy et al., submitted), giving us new clues to decipher the origin of methane. Here, we develop geochemical models to test if the origin of methane could be primordial, derived from CO$_2$ or CO ("abiotic"), or sourced by organics ("thermogenic"). We find that primordial methane is inconsistent with the observational data, whereas both abiotic and thermogenic methane can have D/H ratios that overlap the observed ranges. This suggests that Eris and Makemake either never acquired a significant amount of methane during their formation, or their original inventories were removed and then replaced by a source of internally produced methane. Because producing abiotic or thermogenic methane likely requires temperatures in excess of ~150{\deg}C, we infer that Eris and Makemake have rocky cores that underwent substantial radiogenic heating. Their cores may still be warm/hot enough to produce methane. This heating could have driven hydrothermal circulation at the bottom of an ice-covered ocean to generate abiotic methane, and/or metamorphic reactions involving accreted organic matter could have occurred in response to heating in the deeper interior, generating thermogenic methane. Additional analyses of thermal evolution model results and predictions from modeling of D-H exchange in the solar nebula support our findings of elevated subsurface temperatures and a lack of primordial methane on Eris and Makemake. It remains an open question whether their D/H ratios may have evolved subsequent to methane outgassing. Recommendations are given for future activities to further test proposed scenarios of abiotic and thermogenic methane production on Eris and Makemake, and to explore these worlds up close.Comment: Submitted to Icarus, 29 pages, 5 figures, 1 tabl

Repercussões da infecção por SARS-CoV-2 e da pandemia nas vias de nascimento: estudo transversal

Objetivo: Avaliar as repercussões da infecção por SARS-CoV-2 (suspeita ou confirmada) e do contexto da pandemia na via de nascimento e na assistência humanizada ao parto.Método: Estudo epidemiológico transversal, aninhado a uma coorte e comparativo com a pesquisa “Nascer em Belo Horizonte: Inquérito sobre o Parto e Nascimento”. Avaliou-se prontuários de três maternidades-referência em Belo Horizonte, com amostra final de 1.682 parturientes, nos meses de maio, junho e julho de 2020. Realizou-se análise descritiva, com frequência absoluta e relativa, e comparativa, com teste Qui-quadrado de Pearson.Resultados: Observou-se que, 2,02% das gestantes estavam infectadas por SARS-CoV-2. Antes da pandemia, em um total de 390 gestantes, 74,10% pariram via vaginal. Durante a pandemia, nas mulheres infectadas, 51,61% pariram pela via cesariana e 48,39% pela vaginal; nas não infectadas, 26,99% cesarianas e 73,01% vaginais.Conclusão: Observou-se aumento percentual de cesarianas e possível influência da pandemia nas taxas de indicação de cesarianas no momento da admissão na maternidade. Descritores: COVID-19. Gravidez. Parto. Cesárea. Parto normal

Physical and dynamical characterization of hyperbolic comet C/2017 U7(PANSTARRS)

We present here a dynamical and observational study of the comet C/2017 U7 (PANSTARRS). This comet was discovered in 2017 and found to have a hyperbolic orbit. Our dynamical analysis shows that the object has probably originated in the Oort cloud, however an interstellar origin cannot be discarded. The observations were obtained in 2018 and 2019 using the Goodman High Throughput Spectrograph (GHTS) at the SOAR telescope. We obtained visible spectra covering the wavelength range of and also images in the SDSS filters system. Both the low-resolution reflectance spectrum and the reflectance spectra derived from the SDSS filters show an atypical band at . We conducted a comparative study of the colors and reflectance spectra of different small body populations (e.g., comets, Centaurs, and trans-Neptunian objects or TNOs) from the literature and concluded that the spectra and the colors of this comet are atypical, showing only some overlap with those of some known members of the TNOs and Centaurs, within the large uncertainties of the measurements of those populations. It is found that the feature and overall spectral shape can be reproduced by laboratory spectra of kerite, a template for aliphatic-rich hydrocarbons that has been previously identified in NIR cometary spectra absorptions. It is tentatively proposed that the unusual spectral shape is the result of a particle size distribution of dust grains in the coma or on the surface that has arisen due to a low grain ejection velocity from the surface and large nucleus size

Tópicos de Astronomia para o primeiro ano do ensino médio com base no currículo mínimo do RJ

No ano de 2011 a Secretaria de Educação do Estado do Rio de Janeiro criou o Currículo Mínimo, parâmetro curricular que estabelece o conteúdo mínimo que os alunos da rede estadual de ensino devem aprender durante a sua passagem pelo ensino fundamental e médio. A chegada deste novo parâmetro provocou mudanças no ensino de Física nas escolas e, como consequência, alguns professores se defrontaram com dificuldades para lidar com essas mudanças, pois, além de reorganizar os conteúdos do Ensino Médio, o Currículo Mínimo propõe uma nova abordagem para o ensino de Física. Com o objetivo de auxiliar esses professores na inserção dos conteúdos sugeridos no Currículo Mínimo em sua prática docente, especialmente aqueles relativos aos temas de Astronomia, propomos nesta monografia de conclusão do curso de Licenciatura em Física uma metodologia baseada na formação continuada, fazendo uso de experimentos produzidos com materiais de baixo custo, direcionados para os dois primeiros bimestres do primeiro ano do ensino médio. Esta proposta foi aplicada na forma de minicurso, com duração de 9 horas, cujo público alvo era professores de Física e alunos de períodos avançados de licenciatura. O minicurso foi realizado no Instituto de Física da Universidade Federal Fluminense em julho de 2013, no período de recesso escolar dos professores, e contou com a presença de 30 participantes. No final deste trabalho, a partir da análise dos resultados alcançados com o minicurso e da avaliação das atividades desenvolvidas, foi possível concluir que o evento atingiu seus objetivos e metas, na busca pelo aprimoramento da prática docenteIn 2011 the Department of Education of the State of Rio de Janeiro created the Minimum Curriculum, curriculum parameter that establishes the minimum content that students from state schools should learn during their passage through middle and high school. The arrival of this new parameter caused changes in the Physics teaching in schools and, as a consequence, some teachers were faced with difficulties to deal with these changes, because in addition to rearrange the contents of Secondary Education, the Curriculum Minimum proposes a new approach to Physics teaching. In order to assist these teachers in the insertion of the contents suggested in Minimum Curriculum in their teaching practice, especially those relating to the topics of Astronomy, we propose in this monograph of conclusion of the Bachelor's Degree in Physics, a methodology based on continuing education, making use of experiments produced with low cost materials, addressed to the first bimester of the first year of high school. This proposal was applied in the form of short course, lasting nine hours, whose target audience was physics teachers and students in advanced undergraduate periods. The short course was conducted at the Institute of Physics of the Universidade Federal Fluminense in July 2013, during the school recess of teachers, and was attended by 30 participants. At the end of this work, from the analysis of the results achieved with the short course and evaluation of activities, it was concluded that the event achieved its goals and objectives in the search for improvement of teaching practic

Desenvolvimento e validação de método analítico para quantificação do teor de formaldeído por HPLC em leite

Milk is a food constantly subject to fraud, the most frequent being the addition of water, restoratives and preservatives such as formaldehyde (FA), used to inhibit microbial growth, increasing the shelf life of the product. As new adulteration techniques emerge, new fraud detection methods must be developed in order to maintain the quality and authenticity of the milk. The present work aims to develop and validate a method with trace detection sensitivity and a good ability to resist small variations, in order to quantify FA in milk, using the liquid-liquid extraction technique, together with the liquid chromatography method high-efficiency detector with diode array detection (HPLC-DAD) at a wavelength of 360 nm. For method validation, the analytical parameters of linearity, selectivity, specificity, precision, accuracy, detection limit (LDM), method quantification (LQM) and robustness were applied. The method proved to be linear in the working range of 0.03 to 0.1 mg/L, LDM and LQM of 0.004 mg/kg and 0.01 mg/kg, respectively. The evaluated accuracy presented in the range of 88% to 110% of recovery. Precision showed a coefficient of variation (CV) in the range of 1% to 4%, demonstrating to be selective, precise and accurate. Traces of formaldehyde were found in only one sample with a value above the LQ where the concentration found for DNPH-FA was 0.028 mg/kg with a recovery of 93%. Thus, it can be concluded that the method was effective and could contribute to food security.O leite é um alimento constantemente sujeito a fraudes, sendo as mais frequentes a adição de água, reconstituintes e conservantes como formaldeído (FA), utilizado para inibir o crescimento microbiano, aumentando a vida útil do produto. À medida que novas técnicas de adulteração surgem, novos métodos para detecção de fraudes devem ser desenvolvidos, com a finalidade de manter a qualidade e a autenticidade do leite. O presente trabalho tem como objetivo desenvolver e validar um método com sensibilidade de detecção de traços e uma boa capacidade em resistir a pequenas variações, com intuito de quantificar FA em leite, empregando a técnica de extração líquido-líquido, juntamente com método de cromatografia líquida de alta eficiência com detecção por arranjo de diodos (CLAE-DAD) no comprimento de onda de 360 nm. Para a validação do método aplicou-se os parâmetros analíticos de linearidade, seletividade, especificidade, precisão, exatidão, limite de detecção (LDM), quantificação do método (LQM) e, robustez. O método demonstrou ser linear na faixa de trabalho de 0,03 a 0,1 mg/L, LDM e LQM de 0,004 mg/kg e 0,01 mg/kg, respectivamente. A exatidão avaliada, apresentou na faixa de 88% a 110% de recuperação. A precisão apresentou coeficiente de variação (CV) na faixa de 1% a 4% demonstrando ser seletivo, preciso e exato. Traços de formaldeídos foi encontrada em apenas uma amostra com valor acima do LQ onde a concentração encontrada de DNPH-FA foi de 0,028 mg/kg com recuperação de 93%. Assim podendo concluir que o método foi eficaz e poderá contribuir para a segurança alimentar

Bridging the Gaps: Investigating the Complex Impact of the COVID-19 Pandemic on Tuberculosis Records in Brazil

Background: This study aimed to analyze the temporal evolution, spatial distribution, and impact of the COVID-19 pandemic on tuberculosis records in a northeastern state of Brazil. Methods: This is an ecological study involving all diagnoses of Tuberculosis (TB) in residents of the state of Pernambuco/Brazil. Data were extracted from the National System of Notifiable Diseases. A pre-pandemic COVID-19 temporal analysis (2001–2019), a spatial analysis before (2015–2019) and during the first two pandemic years (2020–2021), and the impact of the COVID-19 pandemic on cases of TB diagnoses in Pernambuco in the years 2020 and 2021 were performed. Inflection point regression models, Global and Local Moran’s statistics, and spatial scan statistics were used. Results: In the period from 2001 to 2019, 91,225 cases of TB were registered in Pernambuco (48.40/100,000 inhabitants), with a tendency of growth starting in 2007 (0.7% per year; p = 0.005). In the pre-pandemic period (2015–2019), 10.8% (n = 20) of Pernambuco municipalities had TB incidence rates below 10/100,000. In 2020, this percentage reached 27.0% (n = 50) and in 2021 it was 17.8% (n = 33). Risk clusters were identified in the eastern region of the state, with five clusters in the pre-pandemic period and in 2021 and six in 2020. In the first year of the pandemic, an 8.5% reduction in the number of new TB cases was observed. In 2021, the state showed a slight increase (1.1%) in the number of new TB cases. Conclusions: The data indicate that the COVID-19 pandemic may have caused a reduction in the number of new TB case reports in the state of Pernambuco, Brazil

Repercussões da infecção por SARS-CoV-2 e da pandemia nas vias de nascimento: estudo transversal

Objetivo: Avaliar as repercussões da infecção por SARS-CoV-2 (suspeita ou confirmada) e do contexto da pandemia na via de nascimento e na assistência humanizada ao parto.Método: Estudo epidemiológico transversal, aninhado a uma coorte e comparativo com a pesquisa “Nascer em Belo Horizonte: Inquérito sobre o Parto e Nascimento”. Avaliou-se prontuários de três maternidades-referência em Belo Horizonte, com amostra final de 1.682 parturientes, nos meses de maio, junho e julho de 2020. Realizou-se análise descritiva, com frequência absoluta e relativa, e comparativa, com teste Qui-quadrado de Pearson.Resultados: Observou-se que, 2,02% das gestantes estavam infectadas por SARS-CoV-2. Antes da pandemia, em um total de 390 gestantes, 74,10% pariram via vaginal. Durante a pandemia, nas mulheres infectadas, 51,61% pariram pela via cesariana e 48,39% pela vaginal; nas não infectadas, 26,99% cesarianas e 73,01% vaginais.Conclusão: Observou-se aumento percentual de cesarianas e possível influência da pandemia nas taxas de indicação de cesarianas no momento da admissão na maternidade. Descritores: COVID-19. Gravidez. Parto. Cesárea. Parto normal

Seminário de Dissertação (2024)

Página da disciplina de Seminário de Dissertação (MPPP, UFPE, 2022) Lista de participantes == https://docs.google.com/spreadsheets/d/1mrULe1y04yPxHUBaF50jhaM1OY8QYJ3zva4N4yvm198/edit#gid=