On the functional form of the metallicity-giant planet correlation

It is generally accepted that the presence of a giant planet is strongly dependent on the stellar metallicity. A stellar mass dependence has also been investigated, but this dependence does not seem as strong as the metallicity dependence. Even for metallicity, however, the exact form of the correlation has not been established. In this paper, we test several scenarios for describing the frequency of giant planets as a function of its host parameters. We perform this test on two volume-limited samples (from CORALIE and HARPS). By using a Bayesian analysis, we quantitatively compared the different scenarios. We confirm that giant planet frequency is indeed a function of metallicity. However, there is no statistical difference between a constant or an exponential function for stars with subsolar metallicities contrary to what has been previously stated in the literature. The dependence on stellar mass could neither be confirmed nor be discarded.Comment: 5 pages, 2 figures, accepted in A&

L’innovation pédagogique vue de l’intérieure

Cet article vise à souligner l’importance de l’ethnographie de l’éducation comme outil pour comprendre et décrire de manière critique les pratiques pédagogiques innovatrices qui ne prennent du sens que lorsqu’elles sont envisagées à partir de l’intérieur, c’est-à-dire du point de vue de leurs praticiens. D’autre part, elle fait le compte-rendu de l’extension de cette méthode d’analyse de l’école, à travers les programmes de Master et de Doctorat de Sciences de l’Education, dans la spécialité d’Innovation Pédagogique de l’Université de Madère et son Centre de Recherche en Education (CIE-UMa), qui se déroulent à Madère, à Santarém (près de Lisbonne) et au Brésil (dans les villes de Brasília, São Luis do Maranhão, Salvador, Ibicaraí, Feira de Santana, Recife et Fortaleza) et qui intègrent une bonne partie de la pensée ethnographique de Lapassade, parmi d’ autres auteurs. Finalement, la communication témoigne de notre hommage en forme d’action à la contribution scientifique de Georges Lapassade

Environmental Epidemiology of Intestinal Schistosomiasis in Uganda: Population Dynamics of Biomphalaria (Gastropoda: Planorbidae) in Lake Albert and Lake Victoria with Observations on Natural Infections with Digenetic Trematodes

This study documented the population dynamics of Biomphalaria and associated natural infections with digenetic trematodes, along the shores of Lake Albert and Lake Victoria, recording local physicochemical factors. Over a two-and-a-half-year study period with monthly sampling, physicochemical factors were measured at 12 survey sites and all freshwater snails were collected. Retained Biomphalaria were subsequently monitored in laboratory aquaria for shedding trematode cercariae, which were classified as either human infective (Schistosoma mansoni) or nonhuman infective. The population dynamics of Biomphalaria differed by location and by lake and had positive relationship with pH (P < 0.001) in both lakes and negative relationship with conductivity (P = 0.04) in Lake Albert. Of the Biomphalaria collected in Lake Albert (N = 6,183), 8.9% were infected with digenetic trematodes of which 15.8% were shedding S. mansoni cercariae and 84.2% with nonhuman infective cercariae. In Lake Victoria, 2.1% of collected Biomphalaria (N = 13,172) were infected with digenetic trematodes with 13.9% shedding S. mansoni cercariae, 85.7% shedding nonhuman infective cercariae, and 0.4% of infected snails shedding both types of cercariae. Upon morphological identification, species of Biomphalaria infected included B. sudanica, B. pfeifferi, and B. stanleyi in Lake Albert and B. sudanica, B. pfeifferi, and B. choanomphala in Lake Victoria. The study found the physicochemical factors that influenced Biomphalaria population and infections. The number and extent of snails shedding S. mansoni cercariae illustrate the high risk of transmission within these lake settings. For better control of this disease, greater effort should be placed on reducing environmental contamination by improvement of local water sanitation and hygiene

Distinguishing the albedo of exoplanets from stellar activity

Light curves show the flux variation from the target star and its orbiting planets as a function of time. In addition to the transit features created by the planets, the flux also includes the reflected light component of each planet, which depends on the planetary albedo. This signal is typically referred to as phase curve and could be easily identified if there were no additional noise. As well as instrumental noise, stellar activity, such as spots, can create a modulation in the data, which may be very difficult to distinguish from the planetary signal. We analyze the limitations imposed by the stellar activity on the detection of the planetary albedo, considering the limitations imposed by the predicted level of instrumental noise and the short duration of the observations planned in the context of the CHEOPS mission. As initial condition, we have assumed that each star is characterized by just one orbiting planet. We built mock light curves that included a realistic stellar activity pattern, the reflected light component of the planet and an instrumental noise level, which we have chosen to be at the same level as predicted for CHEOPS. We then fit these light curves to try to recover the reflected light component, assuming the activity patterns can be modeled with a Gaussian process.We estimate that at least one full stellar rotation is necessary to obtain a reliable detection of the planetary albedo. This result is independent of the level of noise, but it depends on the limitation of the Gaussian process to describe the stellar activity when the light curve time-span is shorter than the stellar rotation. Finally, in presence of typical CHEOPS gaps in the simulations, we confirm that it is still possible to obtain a reliable albedo.Comment: Accepted for publication in A&A, 14 pages, 12 figure

Desenho preliminar de uma coleção nuclear de mandioca dentro do banco ativo de germoplasma da Embrapa Amazônia Ocidental.

A mandioca (Manihot esculenta Crantz) destaca-se como um dos cultivos mais importantes na Amazônia, tanto para a segurança alimentar regional como no comércio. A Embrapa Amazônia Ocidental organizou um Banco Ativo de Germoplasma (BAG) para fins de melhoramento e conservação in vivo da variabilidade genética da mandioca, por meio da coleta de germoplasma em diferentes localidades no Estado do Amazonas, visando reunir a diversidade encontrada na região amazônica. O objetivo deste trabalho foi desenhar uma coleção nuclear de mandioca com base em dados geográficos, morfo-agronômicos e genético-moleculares. Decidiu-se que a Coleção Nuclear deveria conter 50 amostras, representando 15% do BAG e serão representadas por acessos coletados nas calhas dos principais rios Negro, Solimões, Purus, Amazonas e Madeira. As localidades super-representadas no BAG serão alocadas à CN logaritmicamente, enquanto que as localidades sub-representadas serão alocadas proporcionalmente. As amostras selecionadas para a Coleção devem possuir boa produtividade (>13,3 t/há), raízes com polpa de coloração amarelada, teores de HCN acima de 100 mg/kg e divergência genético-moleculares satisfatórias

Formalização e geração de renda: o caso da assessoria à padaria artesanal comunitária "Mãos de Fibra".

Este relato de experiência é originado de um trabalho de extensão com o objetivo de oferecer assessoria técnica e especializada ao empreendimento econômico solidário Padaria Artesanal Comunitária ?Mãos de Fibra?, localizado na zona rural de Viçosa-MG. A Padaria tem a característica de ser predominantemente formada por mulheres rurais. Estas vêm desenvolvendo a produção e comercialização dos pães caseiros. Boa parte da produção resgata a tradição de receitas de seus antepassados. Nessa perspectiva, esta diversidade de produção de alimentos resultou na criação de um novo serviço, denominado ?lanchão?, servidos em eventos. Entre os objetivos específicos, as ações estão orientadas para a formalização do empreendimento em uma associação e para a agregação de valores aos produtos artesanais e agroindustriais já comercializados com a finalidade de qualificar a inserção do grupo em mercados especializados. Entre os resultados, percebe-se que houve melhorias na comunidade desde a formalização do empreendimento ?Associação dos Agricultores Familiares Mãos de Fibra?, pois permitiu a concretização de uma estrutura organizacional formal e autossustentável, possibilitando oferecer condições dignas de trabalho, aumentar a produção e otimizar os resultados econômicos e sociais. Assim, ao capacitar os membros do empreendimento, qualificou-se a possibilidade dessas famílias se tornarem agentes ativos e com papel destacado no processo de desenvolvimento comunitário, contribuindo para a sustentabilidade socioeconômica e criando condições que propiciem melhor renda e qualidade de vida

Contributions to knowledge on the maturation and fertility of the common octopus Octopus vulgaris Cuvier, 1797 on the Portuguese coast

The aim of the present study was to study the reproduction of the common octopus Octopus vulgaris Cuvier, 1797 at three locations on the mainland Portuguese coast. The results showed a higher occurrence of mature females in May-July and November at both Cascais and Santa Luzia, and in February and November at Viana do Castelo. Mature males were found year round. The fertility of females from Santa Luzia was higher (average of 230 000 oocytes), which could be due to this location's more favourable environmental conditions. At Cascais, the average was 140 000 oocytes, and at Viana do Castelo, 120 000. Our results could be useful in drawing up more suitable management measures for octopus Portuguese stocks.El objetivo es el estudio de la reproducción del pulpo común Octopus vulgaris Cuvier 1797 en tres localidades de la costa continental portuguesa. Los resultados demostraron un mayor registro de hembras maduras en mayo-julio y noviembre en Cascais y Santa Luzia, y en febrero y noviembre en Viana do Castelo. Hay machos maduros durante todo el año. La fecundidad de las hembras es mayor en Santa Luzia (con un promedio de 230 000 oocitos), lo que estaría asociado a las condiciones ambientales más favorables de esta localidad. En Cascais y Viana do Castelo el promedio fue de 140 000 y 120 000 oocitos, respectivamente. Estos datos podrán ser útiles para la propuesta de medidas más adecuadas para la gestión de las poblaciones de esta especie en las costas portuguesas.Instituto Español de Oceanografí

Polimorfismo de (GA)n intra e inter SSR em germoplasma mandioca.

O objetivo do trabalho foi comparar o polimorfismo de (GA)n Inter e Intra SSR na análise preliminar de acessos de germoplasma mantidos no Campo Experimental do Caldeirão, município de Iranduba

A new analysis of the WASP-3 system: no evidence for an additional companion

In this work we investigate the problem concerning the presence of additional bodies gravitationally bounded with the WASP-3 system. We present eight new transits of this planet and analyse all the photometric and radial velocity data published so far. We did not observe significant periodicities in the Fourier spectrum of the observed minus calculated (O-C) transit timing and radial velocity diagrams (the highest peak having false-alarm probabilities of 56 per cent and 31 per cent, respectively) or long-term trends. Combining all the available information, we conclude that the radial velocity and transit timing techniques exclude, at 99 per cent confidence limit, any perturber more massive than M \gtrsim 100 M_Earth with periods up to 10 times the period of the inner planet. We also investigate the possible presence of an exomoon on this system and determined that considering the scatter of the O-C transit timing residuals a coplanar exomoon would likely produce detectable transits. This hypothesis is however apparently ruled out by observations conducted by other researchers. In case the orbit of the moon is not coplanar the accuracy of our transit timing and transit duration measurements prevents any significant statement. Interestingly, on the basis of our reanalysis of SOPHIE data we noted that WASP-3 passed from a less active (log R'_hk=-4.95) to a more active (log R'_hk=-4.8) state during the 3 yr monitoring period spanned by the observations. Despite no clear spot crossing has been reported for this system, this analysis claims for a more intensive monitoring of the activity level of this star in order to understand its impact on photometric and radial velocity measurements.Comment: MNRAS accepted (14/08/2012