A mid-IR study of Hickson Compact Groups II. Multi-wavelength analysis of the complete GALEX-Spitzer Sample

We present a comprehensive study on the impact of the environment of compact galaxy groups on the evolution of their members using a multi-wavelength analysis, from the UV to the infrared, for a sample of 32 Hickson compact groups (HCGs) containing 135 galaxies. Fitting the SEDs of all galaxies with the state-of-the-art model of da Cunha (2008) we can accurately calculate their mass, SFR, and extinction, as well as estimate their infrared luminosity and dust content. We compare our findings with samples of field galaxies, early-stage interacting pairs, and cluster galaxies with similar data. We find that classifying the groups as dynamically "old" or "young", depending on whether or not at least one quarter of their members are early-type systems, is physical and consistent with past classifications of HCGs based on their atomic gas content. [...ABRIDGED...] We also examine their SF properties, UV-optical and mid-IR colors, and we conclude that all the evidence point to an evolutionary scenario in which the effects of the group environment and the properties of the galaxy members are not instantaneous. Early on, the influence of close companions to group galaxies is similar to the one of galaxy pairs in the field. However, as the time progresses, the effects of tidal torques and minor merging, shape the morphology and star formation history of the group galaxies, leading to an increase of the fraction of early-type members and a rapid built up of the stellar mass in the remaining late-type galaxies.Comment: Accepted for publication in A&A. Figure resolution degraded for arXiv limits, full resolution paper available at http://www.physics.uoc.gr/~bitsakis/paperII_bitsakis.pd

Avaliação de genótipos de girassol no Planalto Médio do Rio Grande do Sul na safra 2010/2011.

bitstream/item/62564/1/2011boletimdepesquisaonline80.pd

Hydrodynamics and seed dispersal in the lower Amazon.

The transport of seeds by water, i.e. hydrochory, is a key mechanism of long-distance dispersal constrained by the attributes of the seed and hydrodynamics. In the freshwater Amazon estuary, river hydrodynamics are influenced by seasonal changes in precipitation and tidal cycles. It is not known to what extent a hydrodynamic model may be able to predict seed dispersal. Here we parameterised a simulation model (SisBaHia) to estimate maximum seed dispersal distances per tidal cycle, which were then compared with data from in situ seed dispersal experiments. The study was conducted along a 27-km stretch of a tributary of the Amazon estuary, using the seeds of a widely distributed riparian tree?Carapa guianensis (Meliaceae). Based on the simulation model, maximum potential seed dispersal distance was higher in the rainy season (c. 8.7 km) when compared with the dry season (5.6 km), for one tidal cycle (12 hr). The seeds of C. guianensis were dispersed further during the ebb than flood tide during the rainy season, the period of seed dispersal. Average dispersal distances observed in seed dispersal experiments conducted during the rainy season, and those predicted by SisBaHia for the same period were within the same order of magnitude. The results of this study confirm that the period of higher precipitation provides favourable hydrological conditions for hydrochory in the Amazon river-estuary complex. The fact that the time taken for the tide to fall is longer in relation to the time taken for it to rise also favours the arrival of the seeds in the main channel of the Amazon, thereby increasing the probability of long-distance dispersal events

Plantas invasoras no pantanal: como entender o problema e soluções de manejo por meio de diagnóstico participativo.

A invasão de espécies arbóreas e arbustivas em áreas de campos limpos tem diminuído a capacidade produtiva das fazendas, prejudicando o setor pecuário da região.Estas variações podem ser causadas por distúrbios naturais (ciclos plurianuais de cheia e seca e de manejo (fogo, taxa de lotação animal, método de controle/limpeza). Visando auxiliar no entendimento do problema e na busca de soluções sustentáveis, o Centro de Pesquisa do Pantanal (CPP), em parceria com a Embrapa Pantanal e a Universidade Federal de Mato Grosso (UFMT) realizaram o I Workshop da rede Pecuária, reunindo representantes de diversas instituições, fazendeiros de Poconé e todos os interessados. Este trabalho registrou as principais invasoras, as causas da invasão e as soluções de manejo definidas por produtores do Pantanal por meio da aplicação de diagnóstico participativo. As principais invasoras mencionadas foram: pombeiro (Combretum spp.), cambará(Vochysia divergens), conjiqueira (Byrsonima orbignyana) e lixeira (Curatella americana). As informações obtidas foram integradas com os conhecimentos científicos, para a definição de alternativas/soluções a curto, médio e longo prazo.bitstream/item/37290/1/BP66.pd

Épocas de aplicação e fontes nitrogenadas no desenvolvimento do feijoeiro.

O objetivo deste trabalho foi avaliar o efeito da época de aplicação e de fontes nitrogenadas em cobertura no crescimento do feijoeiro cultivado em sistema plantio direto.CONAFE

Estudo dos solos do município de Hulha Negra-RS.

bitstream/item/41231/1/Hulha-negra.pdf; bitstream/item/41232/1/mapa-capacidade-de-uso.pdf; bitstream/item/41233/1/mapa-formas-de-relevo.pdf; bitstream/item/41234/1/mapa-solos.pd

Efeito de culturas de cobertura no pH e teores de cálcio e magnésio do solo sob plantio direto cultivado com feijoeiro.

O presente trabalho teve como objetivo avaliar, após quatro anos, as alterações no pH e nos teores de cálcio e magnésio do solo cultivado com diferentes culturas de cobertura e, adicionalmente, verificar se elas afetam esses atributos após a aplicação de calcário na superfície do solo

Estudo dos solos do município de Candiota.

bitstream/item/41243/1/candiota.pdf; bitstream/item/41244/1/mapa-capacidade-de-uso.pdf; bitstream/item/41246/1/mapa-formas-de-relevo.pdf; bitstream/item/41247/1/mapa-solos.pd

Agronomic performance of super-sweet corn genotypes in the north of Rio de Janeiro.

We investigated the agronomic performance of super-sweet corn genotypes. Super-sweet corn genotypes were backcrossed with regionally adapted field varieties (CIMMYT 8 and Piranão 8). Eight morphological and yield-related traits were evaluated. A significant effect of interaction was observed between the five groups of genotypes (donor parents; super-sweet backcrossed parents; super-sweet intervarietal hybrids; common intervarietal corn hybrids; and field corn populations). Despite the low yield of genotype SH 2 Piranão, the hybrids resulting from interbreeding of the backcrossed parents for the improvement of super-sweet corn were promising. The agronomic performance of the super-sweet parents and their hybrids indicates the possibility of breeding lines with high genetic value to obtain single-cross hybrids and cultivars of super-sweet corn adapted to the northern region of the State of Rio de Janeiro