Astrometry of the main satellites of Uranus: 18 years of observations

We determine accurate positions of the main satellites of Uranus: Miranda, Ariel, Umbriel, Titania, and Oberon. Positions of Uranus, as derived from those of these satellites, are also determined. The observational period spans from 1992 to 2011. All runs were made at the Pico dos Dias Observatory, Brazil. We used the software called Platform for Reduction of Astronomical Images Automatically (PRAIA) to minimise (digital coronography) the influence of the scattered light of Uranus on the astrometric measurements and to determine accurate positions of the main satellites. The positions of Uranus were then indirectly determined by computing the mean differences between the observed and ephemeris positions of these satellites. A series of numerical filters was applied to filter out spurious data. These filters are mostly based on the comparison between the positions of Oberon with those of the other satellites and on the offsets as given by the differences between the observed and ephemeris positions of all satellites. We have, for the overall offsets of the five satellites, -29 (+/-63) mas in right ascension and -27 (+/-46) mas in declination. For the overall difference between the offsets of Oberon and those of the other satellites, we have +3 (+/-30) mas in right ascension and -2 (+/-28) mas in declination. Ephemeris positions for the satellites were determined from DE432+ura111. Comparisons using other modern ephemerides for the solar system -INPOP13c- and for the motion of the satellites -NOE-7-2013- were also made. They confirm that the largest contribution to the offsets we find comes from the motion of the barycenter of the Uranus system around the barycenter of the solar system, as given by the planetary ephemerides. Catalogues with the observed positions are provided.Comment: 13 pages, 21 figure

Perdas e reduções no volume de arroz colhido durante o processo de cultivo, colheita e processamento.

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Aprendizagem e competências transversais: um estudo de caso

Com a implementação do Processo de Bolonha no ensino superior as competências são o eixo central do processo de ensino/aprendizagem, quer na dimensão técnico profissional, quer na perspectiva da transversalidade. Apesar de o conceito de competência transversal não gerar consenso, um dos principais propósitos da actual educação e dos esforços de aprendizagem é dotar os/as estudantes de competências que sejam transferíveis entre contextos e que se encontram para além das abordagens por conteúdos ou áreas do saber. O propósito da investigação que se encontra em curso é o de conceber um perfil de competências transversais do/a profissional de educação, capaz de orientar o trabalho formativo nas instituições de ensino superior, apoiar as tarefas de avaliação e certificação das referidas competências e promover o desenvolvimento pessoal e profissional dos estudantes de 1º ciclo, onde será analisado como estudo de caso a implementação do laboratório de competências transversais no ISCTE, comparando indicadores de desempenho e formas de adesão à transferência de competências por parte dos estudantes. Exercer este papel só é possível, se o professor for um profissional reflexivo, agente da sua própria formação e estimulador da formação do estudante, mediando a construção do conhecimento com actividades lúdicas, reflexivas, desafiadoras e criativas, possibilitando aos estudantes, tornarem-se sujeitos participantes, autónomos e críticos.info:eu-repo/semantics/publishedVersio

Relações da produção de massa verde de Brachiaria brizantha com os índices de disponibilidade de nutrientes em solos sob o Sistema Barreirão de manejo.

Avaliaram-se as relações da produção de massa verde com a disponibilidade dos nutrientes em um latossolo vermelho-escuro, distrófico, fase Cerrado, textura média, em áreas de pastagem provenientes da abertura do cerrado original. Formou-se o pasto, aplicando-se 1,5 t ha-1 de calcário calcítico e semeadura direta com Brachiaria decumbens. Após dez anos de uso, renovou-se a pastagem através do Sistema Barreirão, corrigindo-a com 2,0 t ha-1 de calcário dolomítico. Em uma única operação, semearam-se o arroz e a Brachiaria brizantha mais a adubação nas profundidades de 3 a 5 cm e de 8 a 10 cm, respectivamente. Monitoraram-se áreas com um a seis anos de implantação do sistema, tendo como referências uma área de mata nativa e outra de dezessete anos de pastejo tradicional. Os dados obtidos levam a concluir: i) a relação entre produção de massa verde e teores de matéria orgânica no solo fornece um nível crítico de 19,5 g MO kg-1 de solo, que não pode ser interpretado como indicador confiável de nitrogênio disponível por causa do caráter dinâmico da matéria orgânica no solo; ii) as relações entre produção de massa verde e teores de nutrientes nos solos permitem estabelecer níveis críticos para: cálcio + magnésio trocáveis ? 4,5 cmolc dm-3 de solo, potássio trocável ? 123 mg dm-3, zinco disponível ?1,7 mg Zn dm-3 e cobre disponível ? 2,2 mg Cu dm-3; iii) não foi possível determinar o nível crítico de fósforo disponível pelo extrator Mehlich-1, porque a dose de fosfato aplicada foi insuficiente para sustentar a produtividade do sistema ao longo dos anos

BRS Atalanta: alternativa para o uso racional da água nas lavouras de arroz irrigado do RS.

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Microglia dysfunction caused by the loss of Rhoa disrupts neuronal physiology and leads to neurodegeneration

© 2020 The Author(s). Creative Commons Attribution (CC BY 4.0)Nervous tissue homeostasis requires the regulation of microglia activity. Using conditional gene targeting in mice, we demonstrate that genetic ablation of the small GTPase Rhoa in adult microglia is sufficient to trigger spontaneous microglia activation, producing a neurological phenotype (including synapse and neuron loss, impairment of long-term potentiation [LTP], formation of β-amyloid plaques, and memory deficits). Mechanistically, loss of Rhoa in microglia triggers Src activation and Src-mediated tumor necrosis factor (TNF) production, leading to excitotoxic glutamate secretion. Inhibiting Src in microglia Rhoa-deficient mice attenuates microglia dysregulation and the ensuing neurological phenotype. We also find that the Rhoa/Src signaling pathway is disrupted in microglia of the APP/PS1 mouse model of Alzheimer disease and that low doses of Aβ oligomers trigger microglia neurotoxic polarization through the disruption of Rhoa-to-Src signaling. Overall, our results indicate that disturbing Rho GTPase signaling in microglia can directly cause neurodegeneration.The authors acknowledge the support of the following i3S Scientific Platforms: Animal Facility, Translational Cytometry Unit (TraCy), BioSciences Screening (BS) and Advanced Light Microscopy (ALM), and members of the national infrastructure PPBI-Portuguese Platform of BioImaging (supported by POCI-01–0145-FEDER-022122). FCT Portugal ( PTDC/MED-NEU/31318/2017-031318 ) supported work in the J.B.R. lab. FCT Portugal , PEst ( UID/NEU/04539/2013 ), COMPETE-FEDER ( POCI-01-0145-FEDER-007440 ), Centro 2020 Regional Operational Programme ( CENTRO-01-0145-FEDER-000008 : BrainHealth 2020), and Strategic Project UIDB/04539/2020 and UIDP/04539/2020 (CIBB) supported work in the A.F.A. lab. C.C.P. and R.S. hold employment contracts financed by national funds through FCT (Fundação para a Ciência e a Tecnologia, I.P.) in the context of the program contract described in paragraphs 4, 5, and 6 of article 23 of law no. 57/2016, of August 29th, as amended by law no. 57/2017 of July 19th.info:eu-repo/semantics/publishedVersio

Associations between medical student empathy and personality: A Multi-institutional study

Background: More empathetic physicians are more likely to achieve higher patient satisfaction, adherence to treatments, and health outcomes. In the context of medical education, it is thus important to understand how personality might condition the empathetic development of medical students. Single institutional evidence shows associations between students' personality and empathy. This multi-institutional study aimed to assess such associations across institutions, looking for personality differences between students with high empathy and low empathy levels. Methods: Participants were 472 students from three medical schools in Portugal. They completed validated adaptations to Portuguese of self-report measures of the NEO-Five Factor Inventory(NEO-FFI) and the Jefferson Scale of Physician Empathy(JSPE-spv). Students were categorized into two groups: "Bottom" (low empathy, N = 165) and "Top" (high empathy, N = 169) according to their empathy JSPE-spv total score terciles. Correlation analysis, binary logistic regression analysis and ROC curve analysis were conducted. Results: A regression model with gender, age and university had a predictive power (pseudo R2) for belonging to the top or bottom group of 6.4%. The addition of personality dimensions improved the predictive power to 16.8%. Openness to experience and Agreeableness were important to predict top or bottom empathy scores when gender, age and university were considered." Based on the considered predictors the model correctly classified 69.3% of all students. Conclusions: The present multi-institutional cross-sectional study in Portugal revealed across-school associations between the Big5 dimensions Agreeableness and Openness to experience and the empathy of medical students and that personality made a significant contribution to identify the more empathic students. Therefore, medical schools may need to pay attention to the personality of medical students to understand how to enhance the empathy of medical students