8 research outputs found

    A novel orbiter mission concept for venus with the envision proposal

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    In space exploration, planetary orbiter missions are essential to gain insight into planets as a whole, and to help uncover unanswered scientific questions. In particular, the planets closest to the Earth have been a privileged target of the world’s leading space agencies. EnVision is a mission proposal with the objective of studying Earth’s closest neighbor. Designed for Venus and competing for ESA’s next launch opportunity, the proposal already went through the selective technical review for the M4 launch opportunity, and was submitted to the M5 call, incorporating feedback from ESA. The main goal is to study geological and atmospheric processes, namely surface processes, interior dynamics and atmosphere, to determine the reasons behind Venus and Earth’s radically different evolution despite the planets’ similarities. To achieve these goals, the operational orbit selection is a fundamental element of the mission design process. The design of an orbit around Venus faces specific challenges, such as the impossibility of choosing Sun-synchronous orbits. In this paper, an innovative genetic algorithm optimization was applied to select the optimal orbit based on the parameters with more influence in the mission planning, in particular the mission duration and the coverage of sites of interest on the Venusian surface. After summarizing the EnVision proposal’s mission concept for Venus, the optimization and innovation of the operational orbit design will be analyzed in terms of its benefits to the mission

    Regulatory nodD1 and nodD2 genes of Rhizobium tropici strain CIAT 899 and their roles in the early stages of molecular signaling and host-legume nodulation

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    BACKGROUND: Nodulation and symbiotic nitrogen fixation are mediated by several genes, both of the host legume and of the bacterium. The rhizobial regulatory nodD gene plays a critical role, orchestrating the transcription of the other nodulation genes. Rhizobium tropici strain CIAT 899 is an effective symbiont of several legumes—with an emphasis on common bean (Phaseolus vulgaris)—and is unusual in carrying multiple copies of nodD, the roles of which remain to be elucidated. RESULTS: Phenotypes, Nod factors and gene expression of nodD1 and nodD2 mutants of CIAT 899 were compared with those of the wild type strain, both in the presence and in the absence of the nod-gene-inducing molecules apigenin and salt (NaCl). Differences between the wild type and mutants were observed in swimming motility and IAA (indole acetic acid) synthesis. In the presence of both apigenin and salt, large numbers of Nod factors were detected in CIAT 899, with fewer detected in the mutants. nodC expression was lower in both mutants; differences in nodD1 and nodD2 expression were observed between the wild type and the mutants, with variation according to the inducing molecule, and with a major role of apigenin with nodD1 and of salt with nodD2. In the nodD1 mutant, nodulation was markedly reduced in common bean and abolished in leucaena (Leucaena leucocephala) and siratro (Macroptilium atropurpureum), whereas a mutation in nodD2 reduced nodulation in common bean, but not in the other two legumes. CONCLUSION: Our proposed model considers that full nodulation of common bean by R. tropici requires both nodD1 and nodD2, whereas, in other legume species that might represent the original host, nodD1 plays the major role. In general, nodD2 is an activator of nod-gene transcription, but, in specific conditions, it can slightly repress nodD1. nodD1 and nodD2 play other roles beyond nodulation, such as swimming motility and IAA synthesis. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12864-015-1458-8) contains supplementary material, which is available to authorized users

    Motivos de licenças médicas em um hospital de urgência-emergência Razones de licencias médicas en un hospital de urgencia-emergencia Reason of medical licenses in an emergency hospital

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    Trata-se de um estudo descritivo sobre o absenteísmo-doença entre os trabalhadores de um hospital de grande porte especializado em atendimento de urgência e emergência de Belo Horizonte. Foi analisado o absenteísmo-doença abordando a prevalência, motivo (CID10), tempo de afastamento e risco por categoria profissional. As categorias profissionais foram: serviços de apoio, auxiliares administrativos, enfermagem e medicina. O índice de absentismo-doença no hospital foi de 2,06. A chance de ocorrência de licenças médicas por profissional é 4,7. Este índice foi influenciado pela alta razão prevalente apresentada pela enfermagem (8,48). Os principais motivos de licenças médicas são doenças do sistema osteomuscular e do tecido conjuntivo (14,68%), fatores que influenciam o estado de saúde (13,59%) e doenças do aparelho respiratório (13,32%).<br>Se trata de un estudio descriptivo de la absenteísmo-enfermedad entre los obreros de un hospital de gran carga especializada en la asistencia de urgencia emergencia de Belo Horizonte, en 2002. La absenteísmo-enfermedad que se acercó él prevalecía se analizó, razón (CID10), tiempo y se arriesga para la categoría profesional. Las categorías profesionales eran: servicios de apoyo, administrativo, enfermería y medicina. El índice de absentismo-enfermedad en el hospital era de 2,06. la oportunidad de ocurrencia de licencias médicas para el profesional es 4,7. Este índice se influenció por el prevalente de razón de descarga presentado por la enfermería (8,48). Las razones principales de licencias médicas son enfermedades del osteomuscular del sistema y del tejido conjunto (14,68%), factores que influyen en la condición de salud (13,59%) y enfermedades de la ropa respiratoria (13,32%).<br>This is a descriptive study about the illness-absenteism process among workers in a large emergency hospital in the city of Belo Horizonte, in 2002. The illness- absenteeism process was analyzed considering frequency, reason (DIC10), duration and risk, according to the different professions. The professional categories were: support, administration, nursing and medicine. The rate illness-absenteísm in this hospital was 2,06. The possibility for leave of absence for each profession was 4,7. This rate was influenced by with rate 8,48. Found in the category missing. The main reason for leave of absences was related to orthopedics diseases (14,68%), other health problems (13,59%) and respiratory diseases (13,32%)
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