Deconstructing double-barred galaxies in 2D and 3D. II. Two distinct groups of inner bars

The intrinsic photometric properties of inner and outer stellar bars within 17 double-barred galaxies are thoroughly studied through a photometric analysis consisting of: i) two-dimensional multi-component photometric decompositions, and ii) three-dimensional statistical deprojections for measuring the thickening of bars, thus retrieving their 3D shape. The results are compared with previous measurements obtained with the widely used analysis of integrated light. Large-scale bars in single- and double-barred systems show similar sizes, and inner bars may be longer than outer bars in different galaxies. We find two distinct groups of inner bars attending to their in-plane length and ellipticity, resulting in a bimodal behaviour for the inner/outer bar length ratio. Such bimodality is related neither to the properties of the host galaxy nor the dominant bulge, and it does not show a counterpart in the dimension off the disc plane. The group of long inner bars lays at the lower end of the outer bar length vs. ellipticity correlation, whereas the short inner bars are out of that relation. We suggest that this behaviour could be due to either a different nature of the inner discs from which the inner bars are dynamically formed, or a different assembly stage for the inner bars. This last possibility would imply that the dynamical assembly of inner bars is a slow process taking several Gyr to happen. We have also explored whether all large-scale bars are prone to develop an inner bar at some stage of their lives, possibility we cannot fully confirm or discard.Comment: 14 pages, 8 figures, 1 table. Accepted for publication in MNRA

Compostagem laminar em sistema orgânico de banana.

A utilização de práticas agrícolas não convencionais capazes de melhorar os atributos físicos, químicos e biológicos do solo é fundamental no sistema orgânico. A compostagem laminar, com o aproveitamento de resíduos orgânicos de baixo custo e fácil disponibilidade, é uma alternativa que pode ser viável.PDF. 139_11

Ecologização da agricultura e das relações inovadoras com o mercado: situação atual e perspectivas no Brasil.

Este texto analisa o desenvolvimento da agricultura agroecológica e orgânica no Brasil. Apresenta uma grande diversidade social e de modelos de produção reconhecidos pela legislação brasileira: orgânica, agroecológica, ecológica, biodinâmica, permacultura, etc. Descreve sinteticamente como as políticas e os interesses sociais ligados às questões da agricultura familiar e do meio ambiente causaram a reorganização dos sistemas de produção, em termos de práticas agrícolas e de novas relações com mercados e com os recursos naturais. A análise foi baseada em entrevistas com agricultores e agentes envolvidos no desenvolvimento de vários modelos orgânicos; qualifica os modelos de produção assim como os valores socioculturais relacionados. Apresenta também alguns aspectos das raízes históricas do movimento agroecológico brasileiro e as maneiras como os agricultores familiares se adaptam aos novos interesses da produção ecológica

Young peoples’ reflections on what teachers think about family obligations that conflict with school: A focus on the non-normative roles of young caring and language brokering

In “Western” contexts school attendance is central for an ‘ideal’ childhood. However, many young people engage with home roles that conflict with school expectations. This paper explores perceptions of that process in relation two home activities - language brokering and young caring. We interviewed 46 young people and asked them to reflect on what the teacher would think when a child had to miss school to help a family member. This paper discusses the young people’s overall need to keep their out-of-school lives private from their teachers

Selection of common bean inbred lines with tolerance to high moisture at harvest.

The occurrence of precipitation / rain in harvest bean causes damage to the product and reduces the yield. The main alternative to mitigate this problem is to obtain cultivars presenting low germination of beans in the pods under conditions of high moisture. The purpose of this study was to verify if there is genetic variability among the common bean inbred lines that are in the phase of recommendation for the South of Minas Gerais, Brazil in regard to tolerance to moisture after harvest, and identify traits that may be routinely used in selection of tolerant lines to these conditions. Ninety-five lines in the phase of recommendation by the Genetic Breeding Program from UFLA were used. After harvest, a sample of plants from each plot was removed for assessments of seed germination in the pods in a moist chamber and water absorption by pod and seed. Eight days after harvest, another sample was removed to assess seed appearance using a scoring scale. The data were submitted to analysis of variance and estimates of the Pearson phenotypic correlations were obtained among traits. Lines differ in relation to tolerance to moisture at the time of harvest, with those of higher tolerance having lighter colored seeds. The main difficulty in selection of common bean lines for tolerance to high moisture at harvest is the repeatability of the environmental conditions among crop seasons. The alternative is assessing the amount of water absorbed by pods

Seleção de progênies de feijoeiro com plantas eretas e grãos tipo carioca.

Para confirmar se a população oriunda do cruzamento CVIII-8511 x BRS-Supremo, identificada em um cruzamento dialélico anteriormente realizado é realmente promissora para a seleção de plantas eretas e com boa produtividade de grãos foi realizado o presente trabalho

Taxa de semeadura de Arachis pintoi cv. Mandobi para formação de pastos consorciados.

O presente estudo foi conduzido com o objetivo de determinar a taxa de semeadura da leguminosa Arachis pintoi cv. Mandobi para a formação de pasto consorciado com a Brachiaria humidicola cv. Tupi. Foram testadas quatro taxas de semeadura (3, 6, 12 e 24 kg/ha de sementes puras germináveis), no delineamento em blocos ao acaso, com quatro repetições. A gramínea foi semeada com taxa constante de 4,5 kg/ha de sementes puras germináveis. Aos 21 e 70 dias após a semeadura, foram avaliadas a densidade de plantas da gramínea e da leguminosa, o grau de cobertura do solo, o vigor das plantas da cv.. Mandobi e a composição botânica do pasto. O aumento da taxa de semeadura da cv. Mandobi resultou em aumento linear do estande inicial da leguminosa, sem afetar o estande da gramínea aos 21 dias após a semeadura. Aos 70 dias após a semeadura, observou-se que o uso de maiores taxas de semeadura da leguminosa resultou em um pasto mais equilibrado, com menor participação do capim-tupi e de outras gramíneas e maior participação da cultivar Mandobi. Dessa forma, a taxa de semeadura mínima da cv. Mandobi para formação de pastos consorciados com o capim-tupi deve ser de 12 kg/ha de sementes puras germináveis

Animal production from new Panicum maximum genotypes in the Amazon biome, Brazil.

The Panicum maximum breeding program coordinated by the Brazilian Agricultural Research Corporation (Embrapa) has been evaluating and selecting genotypes under different soil and climatic conditions, with the objective to release new cultivars adapted to the diverse regions of Brazil. For the Amazon biome, small-plot experiments carried out in Acre between 2003 and 2005 allowed the selection of some promising genotypes (Valentim and Andrade 2005; Valentim et al. 2006; Andrade and Valentim 2009), with higher potential for forage growth than cultivars on the market. The objective of this work was to compare 2 new P. maximum genotypes with cv. Tanzânia in relation to carrying capacity and animal performance, when managed under rotational stocking in the Amazon biome