Titan

The following topics are discussed with respect to Titan: observations of the atmosphere; laboratory simulations and theoretical models of Titan's atmosphere; endpoints of atmospheric chemistry - aerosols and oceans; exobiology; and the next steps in understanding Titan

Chiral Metal Surfaces and Nanoparticles

The surface of metals can exhibit intrinsic chiral structure. Furthermore, chirality can be bestowed onto achiral metal surfaces by adsorption of chiral molecules. Such chiral metal surfaces are promising as heterogeneous enantioselective catalysts and may furthermore be used for the separation and detection of enantiomers. Similarly, metal nanoparticles can be chiral, which is reflected by their optical activity in metal-based electronic transitions. The transfer of chirality from adsorbate to the metal surface depends on the structure of the former, which is however difficult to elucidate. It is shown that vibrational circular dichroism can be used to determine the structure of a chiral adsorbed molecule and the way it interacts with the metal

Regulation by territorialization: the political ecology of conservation and development territories

Introduction Under the banners of environmental conservation, food security, and sustainable development, a diverse group of public and private actors is busily dividing the global South into conservation and development territories at a variety of scales. Multiple goals and processes drive these spatial strategies to reconfigure resource access, control, and management. The production of territory to regulate populations and resources has a long tradition (Elden, 2013; Sack, 1986; Scott, 199..

Bibliographie

Cette bibliographie est proposée par les coordinateurs du dossier en complément de la liste des notices bibliographiques BGI. Adams W., Hutton J., 2007. People, Parks and Poverty: Political Ecology and Biodiversity Conservation. Conservation & Society, 5(2), p. 147-183 p. Adger W. N., Benjaminsen T. A., Brown K. et Svarstad H., 2001. Advancing a political ecology of global environmental discourses. Development and Change, 32 (4), p. 681-715. Agrawal A., 2005. Environmentality: Technologies of..

Evaluation du coût de la mammite clinique: une méta-analyse

La mammite est la première pathologie rencontrée en élevage laitier. Elle est la première cause de consommation d’antibiotique en élevage et engendre des pertes de rentabilité importantes. Cette étude propose une méta-analyse sur le coût d'un cas de mammite clinique dans un élevage bovin laitier. La constitution de la base de données et la conduite de la méta-régression ont été réalisées selon les procédures habituelles. Le coût moyen par cas clinique est évalué à 224 € par cas pour toutes les étiologies, à 457 et 101 € par cas de mammite clinique à respectivement bactérie Gram négative et positive, et à 428 et 74 € par cas de mammite clinique à Escherichia coli ou Staphylococcus aureus, respectivement. Les résultats sur les liens entre coût total d’un cas de mammite et (i) valeurs monétaire des contributeurs et (ii) paramètres économiques d’entrée des modèles sources doivent être interprétés avec précaution. Des développements supplémentaires sont donc nécessaires autant à court qu’à moyen termes, et dans divers systèmes de production et contextes macro-économiques

Essays in development economics

This dissertation consists of three chapters in development economics which investigate questions related to intergroup contact and the consequences of civil conflicts. In the first chapter, I study how refugee networks influence social integration in the host community in the context of Turkey, a country that has been profoundly impacted by the arrival of more than 3.5 million Syrian refugees since 2011. Using a rich dataset on the mobile phone communications of Syrian refugees, I construct village-level measures of refugee presence and social integration. In villages with a larger refugee population, refugees made significantly more phone calls to locals and other refugees, and a higher proportion of their calls were placed to locals. I argue that refugee networks made it easier for their members to interact with locals by sharing information on local norms and creating new opportunities to meet locals. The second chapter examines how the cost of inter-ethnic contact influences inter-ethnic relations. The study uses the staggered improvements of the Indonesian road network during the 1990s and shows that it lowered the cost of intergroup contact. The resulting enhancement in access to other ethnic groups led to increasing rates of inter-ethnic marriages. The third chapter investigates the long-run effects of civil conflicts on human capital that owe their impact to family structure. Specifically, I study how the loss of a sibling during the 1994 genocide against Tutsis in Rwanda affected surviving children. The loss of a sibling had positive effects on human capital and negative effects on wealth. I argue that these results are consistent with standard models of fertility choice, although other mechanisms could also have played a role

Resonant metamaterial absorbers for infrared spectral filtering: quasimodal analysis, design, fabrication and characterization

We present a modal analysis of metal-insulator-metal (MIM) based metamaterials in the far infrared region. These structures can be used as resonant reflection bandcut spectral filters that are independent of the polarization and direction of incidence because of the excitation of quasimodes (modes associated with a complex frequency) leading to quasi-total absorption. We fabricated large area samples made of chromium nanorod gratings on top of Si/Cr layers deposited on silicon substrate and measurements by Fourier Transform spectrophotometry show good agreement with finite element simulations. A quasimodal expansion method is developed to obtain a reduced order model that fits very well full wave simulations and that highlights excitation conditions of the modes.Comment: 8 pages, 7 figure

On non-rank facets of the stable set polytope of claw-free graphs and circulant graphs

We deal with non-rank facets of the stable set polytope of claw-free graphs. We extend results of Giles and Trotter [7] by (i) showing that for any nonnegative integer a there exists a circulant graph whose stable set polytope has a facet-inducing inequality with (a,a+1)-valued coefficients (rank facets have only coefficients 0, 1), and (ii) providing new facets of the stable set polytope with up to five different non-zero coefficients for claw-free graphs. We prove that coefficients have to be consecutive in any facet with exactly two different non-zero coefficients (assuming they are relatively prime). Last but not least, we present a complete description of the stable set polytope for graphs with stability number 2, already observed by Cook [3] and Shepherd [18

Imaging of Early-Stage Cracking on Real-Size Concrete Structure from 4-Points Bending Test

International audienceTraditional ultrasonic imaging techniques encounter difficulty on complexes material such as concrete, which is in part due the use of coherent waves in a very heterogeneous material. From this angle, technique called LOCADIFF has been developed for monitoring heterogeneous media using multiply scattered waves [1, 2]. We consider that modifications in the medium are equivalent to the presence of extra scatterers, which are characterized by their effective scattering cross-section &#963,. Within this view, LOCADIFF allows to locate the modification by measuring the spatio-temporal de-correlation of multiply scattered waves and by solving the corresponding inverse problem. Based on LOCADIFF, a newly developed imaging technique has been reported [3]. By mapping the intensity of modification on localized microstructure, the new technique is able to detect perturbations at multiple locations. Here we present the application of this new technique on a real-size 15 tons concrete structure for imaging early-stage cracking procedure issued from four point bending load, as part of the CEOS.fr project. Experimental results show that this technique can not only locate cracks that appeared simultaneously at multiple locations, but also detect them and observe their developments since an early-stage