de Broglie-Proca and Bopp-Podolsky massive photon gases in cosmology

We investigate the influence of massive photons on the evolution of the expanding universe. Two particular models for generalized electrodynamics are considered, namely de Broglie-Proca and Bopp-Podolsky electrodynamics. We obtain the equation of state (EOS) $P=P(\varepsilon)$ for each case using dispersion relations derived from both theories. The EOS are inputted into the Friedmann equations of a homogeneous and isotropic space-time to determine the cosmic scale factor $a(t)$. It is shown that the photon non-null mass does not significantly alter the result $a\propto t^{1/2}$ valid for a massless photon gas; this is true either in de Broglie-Proca's case (where the photon mass $m$ is extremely small) or in Bopp-Podolsky theory (for which $m$ is extremely large).Comment: 8 pages, 2 figures; v2 matches the published versio

On the fate of dead coral colonies

Carbonate budgets dynamically balance production and loss of calcium carbonate (CaCO3) on coral reefs. To sustain or expand the coral reef framework, CaCO3 production by calcifying organisms must be higher than erosion. However, global climate change has been negatively impacting carbonate production, with bleaching events causing widespread coral mortality. Although bleaching and coral mortality are well documented, the fate of coral colonies after their death, including their erosion rates, are still poorly known. We followed the fate of 143 recently dead individual coral colonies with complex growth forms (arborescent, caespitose, corymbose, digitate and tabular), whose mortality was triggered by two consecutive bleaching events. These colonies, spread over 16 km2 of the Lizard Island reef complex, were tracked for up to 5 years, allowing detailed examination of erosion rates and post-mortality structural persistence. We also tested how variables that are commonly used in coral reef erosion studies relate to spatial and temporal variability in the erosion rates of dead coral colonies. We revealed rapid erosion of dead coral colonies, with an average of 79.7% of dead colonies completely disintegrating within 60 months. The predicted half-life of a dead coral colony was 40 months, with limited variation among wave exposure levels. Remarkably, we found no effect of estimated parrotfish bioerosion, wave exposure, nor coral growth form, on observed erosion rates. Our results suggest that our understanding of the erosion of dead corals may be more limited than previously thought. The rapid loss of coral colonies on our study sites calls for a re-evaluation of the role of corals with complex growth forms in reef growth and of parrotfishes in reef erosion

Sistematização de dados bibliográficos relacionados aos impactos ambientais da produção agrícola sobre as águas fluviais no corredor de Nacala, Moçambique.

Resumo: As atividades do bolsista foram desenvolvidas no escopo do ProSAVANA-TEC (Projeto de Melhoria da Capacidade de Pesquisa e de Transferência de Tecnologia para o Desenvolvimento da Agricultura no Corredor de Nacala em Moçambique), organizando levantamentos bibliográficos de informações disponíveis na internet sobre a qualidade da água superficial nas bacias hidrográficas localizadas na região do Corredor de Nacala e em Moçambique como um todo. A organização do material bibliográfico foi realizada por meio dos programas computacionais "ZOTERO", "MENDELEY.COM" e "MENDELEY- DESKTOP". Por fim, obteve-se uma coletânea de material bibliográfico, organizado digitalmente, para otimizar as consultas bibliográficas dos membros da equipe do ProSavana, assim como de outros interessados nos temas desta coletânea, assim facilitada pelo uso da ferramenta computacional selecionada. Abstract: The activities of the grantee have been developed within the scope of ProSavana-TEC (Project Capacity Enhancement of Research and Technology Transfer for the Development of Agriculture in the Nacala Corridor in Mozambique), organizing bibliographic information available on the internet about the surface water quality in the river basins located in the region of the Nacala Corridor as well as Mozambique as a whole. The organization of the bibliographic material was performed by the use of the softwares"Zotero", "MENDELEY.COM" and "Mendeley-DESKTOP". Finally, we obtained a collection of bibliographic material, that was digitally organized, to optimize the bibliographic queries of theProSavana team members as well as queries of other people interested in topics of this collection , which access will be facilitated by the use of the selected computational tools

Ovinos Santa Inês: estado de arte e perspectivas.

[Santa Inês hair sheep: state of art and perspectives]. Abstract: The Santa Inês hair sheep breed is found in whole to areas of Brazil. Its origin has been object of vary speculations. However, the most probable could be traced starting from combinations of four genetic sources: a) Criuola is wool type of sheep, brought by Portuguese and Spanish settlers, but that eliminated the wool under tropical conditions was; b) Hair sheep breeds originating from of the African continent, which originated most of the hair sheep breeds from Brazil, Central America and Caribbean; c) Bergamácia sheep breed from Italian, which was crossed with the remaining sheep of those originating from of the African continent, and Morada Nova, followed by adaptation, selection and evolution for absence of wool; d) finally, in the end of the decade of 80, a small group of the breeders added to Santa Inês the Somalis and Suffolk breeds. The breed presents good reproductive, adaptability and growth potential. The pattern of the coat calor includes the white, the red, the black and the mailed. In field conditions the ewes reach weights of 40-60 kg and the males can reach up to 120 kg. The selection practiced in the breed has been done in direction for size and body weight, absence of wool and horns and, presence of an intense pigmentation. The females present good maternal ability and they get easily to give birth vigorous lambs. The age to the puberty and first lambing, lambing interval, fertility, the prolificacy and the survival rate from weaning found in the literature, vary from: 274 to 376 days, 442 to 551 days, 227 to 307 days, 83,6 to 93%, 1,1 to 1,4 and, from 69 to 87%, respectively. The Santa Inês lamb can reach 23-32 kg at weaning and gain 166 -336 kg. At slaughter, Santa Inês Lamb, had dressing percentage of approximately 48,0 %. The animals generally demonstrate capacity to develop a strong answer immunology against the nematodes gastrontestinais, even before of the weaning. That skin presents great market value, due to the high quality pattern, resultant of its largest elasticity and excellent flexibility, and great resistance, associated to a fine texture, being rendered for use in several manufactured products. In spite of the few studies involving the face Santa Inês the breed has been demonstrating to be an excellent alternative to increase the production of meat in the main areas of the country, considering its reproductive capacity, resistance sponges it gastrontestinais, skin quality and adaptability , besides good growth rate