Identification of the minimal promoter region of the mouse NKX5-3, a transcription factor implicated in eye development.

Early ocular development is controlled by a complex network of transcription factors, cell cycle regulators, and diffusible signalling molecules. Together, these molecules regulate cell proliferation and apoptosis, and specify retinal fate. NKX5-3 is a homeobox transcription factor implicated in eye development. The analysis of the 5'-flanking region of the mouse Nkx5-3 gene revealed a predicted TATA-less promoter sequence between -416 and -166 of the translation start site. To functionally characterise Nkx5-3 promoter activity, serial deletions of the promoter sequence were introduced in pGL-3 basic vector and promoter activity of these 5'- and 3'-deleted constructions was tested in HeLa and CHO cells. Transactivation assays identified a region between -350 and -296 exhibiting promoter-like activity. Combined analysis by deletions and point mutations showed that this sequence, containing multiple Sp1 binding sites was necessary to promote transcriptional activity. Binding of Sp1 to this region was confirmed by electrophoretic mobility shift assay (EMSA) and chromatin immunoprecipitation, using an antibody specific for Sp1. Altogether, these results demonstrated that the immediate upstream region of Nkx5-3 gene possessed a strong intrinsic promoter activity in vitro, suggesting a potential role in Nkx5-3 transcription in vivo.

Occurrence of Symphyla (Myriapoda) in the region of the Upper Solimões River, Amazonas, Brazil

The present work aimed at identifying the Symphyla species diversity and abundance in various land-use systems under different degrees of intensification in western Amazonia. This is the first inventory of Symphyla in primary and secondary forest, crops, agroforestry systems and pastures which was carried out in Benjamin Constant municipality, in the region of the Upper Solimões River, Brazil. Samples (n = 101) were collected using a metal corer, and the symphylan extraction was carried out using Berlese-Tullgren funnels. Two genera and three species of symphylans were encountered. Considering the diversity encountered in Amazonian inventories, with only four genera and five known species overall, the three species found in the present study are considered a reasonable representation of the regional diversity. Two of the Hanseniella species found have been known to cause plant damage.

The earthworm fauna of regenerating forests and anthropogenic habitats in the coastal region of Paraná

The aim of this study was to evaluate abundance, biomass and diversity of earthworms in the southern coast region of the Mata Atlântica biodiversity hotspot. A total of 51 study sites in pastures, banana monocultures, mixed agroforestry systems, secondary forests in succession and old-growth forests near the coast of Paraná, Brazil, were evaluated. Each site was sampled once. Species richness of the earthworms was generally low and varied little between sites. At all sites except for one, the peregrine species Pontoscolex corethrurus (Glossoscolecidae) strongly dominated. Three other peregrine species, Amynthas corticis, Amynthas gracilis (Megascolecidae) and Ocnerodrilus occidentalis (Ocnerodrilidae), were frequent in moist sites. No autochthonous species were found. Abundance and biomass of earthworms varied strongly within and between sites (0-338 individuals m-2, 0-96 g m-2 fresh weight). Pastures had significantly lower abundance than all other sites. The forest sites had similar earthworm abundance and biomass, with a tendency to be higher in younger succession stages. The coastal plain region has been strongly altered by human activities. Reasons for the lack of any autochthonous species and the dominance of one peregrine species require further investigation.

[Défilé du 14 juillet 1919 sous l'Arc de triomphe de l'Etoile] : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 54922

[Défilé du 14 juillet 1919 sous l'Arc de triomphe de l'Etoile] : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 54923

Solar radiation use efficiency by soybean under field conditions in the Amazon region

The objective of this work was to evaluate the efficiency of soybean (Glycine max) in intercepting and using solar radiation under natural field conditions, in the Amazon region, Brazil. The meteorological data and the values of soybean growth and leaf area were obtained from an agrometeorological experiment carried out in Paragominas, Pará state, during 2007 and 2008. The radiation use efficiency (RUE) was obtained from the ratio between the above-ground biomass production and the intercepted photosynthetically active radiation (PAR) accumulated to 99 and 95 days after sowing, in 2007 and 2008, respectively. Climatic conditions during the experiment were very distinct, with reduction in rainfall in 2007, which began during the soybean mid-cycle, due to the El Niño phenomenon. An important reduction in the leaf area index and biomass production was observed during 2007. Under natural field conditions in the Amazon region, the values of RUE were 1.46 and 1.99 g MJ-1 PAR in the 2007 and 2008 experiments, respectively. The probable reason for the differences found between these years might be associated to the water restriction in 2007 coupled with the higher air temperature and vapor pressure deficit, and also to the increase in the fraction of diffuse radiation that reached the land surface in 2008.

[Défilé du 14 juillet 1919 sous l'Arc de triomphe de l'Etoile, tanks] : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 54925

[Défilé du 14 juillet 1919, les tanks passent sous l'Arc de triomphe de l'Etoile] : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 54945

[Défilé du 14 juillet 1919, soldats américains passant sous l'Arc de triomphe de l'Etoile] : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 54951

[Défilé du 14 juillet 1919 passant sous l'Arc de triomphe de l'Etoile] : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 54952

[Défilé du 14 juillet 1919 passant sous l'Arc de triomphe de l'Etoile, armée française] : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 54953

[Défilé du 14 juillet 1919 passant sous l'Arc de triomphe de l'Etoile, véhicules blindés] : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 54954

[Défilé du 14 juillet 1919 passant sous l'Arc de triomphe de l'Etoile, armée française] : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 54956