Earthshine observation of vegetation and implication for life detection on other planets - A review of 2001 - 2006 works

The detection of exolife is one of the goals of very ambitious future space missions that aim to take direct images of Earth-like planets. While associations of simple molecules present in the planet's atmosphere ($O_2$, $O_3$, $CO_2$ etc.) have been identified as possible global biomarkers, we review here the detectability of a signature of life from the planet's surface, i.e. the green vegetation. The vegetation reflectance has indeed a specific spectrum, with a sharp edge around 700 nm, known as the "Vegetation Red Edge" (VRE). Moreover vegetation covers a large surface of emerged lands, from tropical evergreen forest to shrub tundra. Thus considering it as a potential global biomarker is relevant. Earthshine allows to observe the Earth as a distant planet, i.e. without spatial resolution. Since 2001, Earthshine observations have been used by several authors to test and quantify the detectability of the VRE in the Earth spectrum. The egetation spectral signature is detected as a small 'positive shift' of a few percents above the continuum, starting at 700 nm. This signature appears in most spectra, and its strength is correlated with the Earth's phase (visible land versus visible ocean). The observations show that detecting the VRE on Earth requires a photometric relative accuracy of 1% or better. Detecting something equivalent on an Earth-like planet will therefore remain challenging, moreover considering the possibility of mineral artifacts and the question of 'red edge' universality in the Universe.Comment: Invited talk in "Strategies for Life Detection" (ISSI Bern, 24-28 April 2006) to appear in a hardcopy volume of the ISSI Space Science Series, Eds, J. Bada et al., and also in an issue of Space Science Reviews. 13 pages, 8 figures, 1 tabl

Development of a practice guideline for dietary counselling of children with IgE-mediated food allergy

Purpose The incidence of food allergy is increasing globally and whilst there is consensus that dietitians should be involved in its management, the roles that dietitians should fulfill differ between different guidelines and the description of tasks remains unclear. Currently, no Swiss guideline exists to assist dietitians in counselling children with food allergies. There is a need for recommendations that will guide dietitians through the counselling process. The aim of this project was to create a practice guideline for dietary counselling of children with food allergy. Methods Practice guidelines were developed following the Academy of Nutrition and Dietetics stepwise approach. The process consisted of six steps: (1) Determine the scope oft he guideline. (2) Conduct a systematic review. (3) Draft the guideline recommendations using the Nutrition Care Process (NCP) as a framework. (4) Finalise the guideline during a face-to-face meeting. (5) Conduct internal and external review and revise accordingly. (6) Publish guideline. Results The process resulted in 25 recommendations for dietary counselling. Most recommendations are based on expert opinion only, due to the lack of studies in this field and showed similar levels of consensus between the expert group and external review by allergists. However, there were nine recommendations where the consensus differed. Conclusion This guideline provides a comprehensive guide to dietary counselling for food allergy by dietitians in Switzerland. It will inform best practice and improve patient-centred care and encourage a consistent approach, but it will need to be reviewed and updated as more robust evidence is produced

International Science Foresight Workshop: Global Challenges and Research Gaps. The Royaumont process.

How scientists might better contribute to SDGs in the land sector? At the invitation of INRAE, a group of high-level international experts delivers a comprehensive and systemic approach

Biomarqueurs enzymatiques et génotoxiques pour l'évaluation des effets des polluants sur les poissons de la rivière Moselle

Response of aquatic organisms to pollutants has been studied following different biomarkers in feral fish at different locations of the Moselle River (France). Both ethoxyresorufin O-deethylase (EROD) and acetylcholinesterase (AChE) activities were measured respectively in the liver and muscle of chub (Leuciscus cephalus) caught by electrofishing. Parallel to this, level of DNA damage (in terms of DNA single strand breaks) was quantified in chub erythrocytes applying the comet assay. Results show a strong difference between males and females in consideration of EROD activity exhibiting 10 fold-values in males compared to females, but not for DNA damage and AChE activity. Moreover response of the 3 biomarkers does not depend on size of fish (highly correlated to their age). EROD activity appears to be induced in males and females according to a growing gradient between upstream and downstream stations but level of DNA damage follows an inverse tendency (i.e. fish from upstream stations exhibit a higher DNA damage than those downstream). Chemical analyses of organic and metallic compounds both in fish muscle and sediment do not clearly explain the responses of studied biomarkers. This study points out the difficulty to assess effects of pollutants in the case of complex contamination and highlights the necessity to use a large array of biomarkers at different levels of biological organisation.Cette étude menée par des laboratoires du Cemagref et de l'ENTPE s'inscrit dans le cadre du programme "PNETOX", destiné à évaluer et comparer des biomarqueurs et des indicateurs biologiques sur des poissons et des invertébrés de la Moselle sur 4 stations réparties à l'amont de Nancy en juin 1998. Il ressort de ces mesures une induction de l'activité EROD chez les cyprinidés de plus en plus marquée de l'amont vers l'aval. L'activité AChE ne présente quant à elle pas d'effet station. Enfin, l'impact génotoxique semble plus marqué pour les trois stations les plus amont. Les résultats de ces biomarqueurs sont à confronter aux mesures de bioaccumulation toxique dans les poissons et aux mesures de contamination dans les sédiments