Control of the Platinum(II) ligating properties of rigid 1,2-diamines: the case of trans-2,3-diaminonorbornane.

Guided by a simple predictive model, a norbornane-based trans-1,2-diamine was identified as a potential bridging ligand for di-nuclear platinum complex formation; efficient synthesis and product characterization confirmed this hypothesis

Role of Hypothalamic Melanocortin System in Adaptation of Food Intake to Food Protein Increase in Mice

The hypothalamic melanocortin system—the melanocortin receptor of type 4 (MC4R) and its ligands: α-melanin-stimulating hormone (α-MSH, agonist, inducing hypophagia), and agouti-related protein (AgRP, antagonist, inducing hyperphagia)—is considered to play a central role in the control of food intake. We tested its implication in the mediation of the hunger-curbing effects of protein-enriched diets (PED) in mice. Whereas there was a 20% decrease in food intake in mice fed on the PED, compared to mice fed on an isocaloric starch-enriched diet, there was a paradoxical decrease in expression of the hypothalamic proopiomelanocortin gene, precursor of α-MSH, and increase in expression of the gene encoding AgRP. The hypophagia effect of PED took place in mice with invalidation of either MC4R or POMC, and was even strengthened in mice with ablation of the AgRP-expressing neurons. These data strongly suggest that the hypothalamic melanocortin system does not mediate the hunger-curbing effects induced by changes in the macronutrient composition of food. Rather, the role of this system might be to defend the body against the variations in food intake generated by the nutritional environment

Gene expression in a paleopolyploid: a transcriptome resource for the ciliate Paramecium tetraurelia

International audienceBACKGROUND: The genome of Paramecium tetraurelia, a unicellular model that belongs to the ciliate phylum, has been shaped by at least 3 successive whole genome duplications (WGD). These dramatic events, which have also been documented in plants, animals and fungi, are resolved over evolutionary time by the loss of one duplicate for the majority of genes. Thanks to a low rate of large scale genome rearrangement in Paramecium, an unprecedented large number of gene duplicates of different ages have been identified, making this organism an outstanding model to investigate the evolutionary consequences of polyploidization. The most recent WGD, with 51% of pre-duplication genes still in 2 copies, provides a snapshot of a phase of rapid gene loss that is not accessible in more ancient polyploids such as yeast. RESULTS: We designed a custom oligonucleotide microarray platform for P. tetraurelia genome-wide expression profiling and used the platform to measure gene expression during 1) the sexual cycle of autogamy, 2) growth of new cilia in response to deciliation and 3) biogenesis of secretory granules after massive exocytosis. Genes that are differentially expressed during these time course experiments have expression patterns consistent with a very low rate of subfunctionalization (partition of ancestral functions between duplicated genes) in particular since the most recent polyploidization event. CONCLUSIONS: A public transcriptome resource is now available for Paramecium tetraurelia. The resource has been integrated into the ParameciumDB model organism database, providing searchable access to the data. The microarray platform, freely available through NimbleGen Systems, provides a robust, cost-effective approach for genome-wide expression profiling in P. tetraurelia. The expression data support previous studies showing that at short evolutionary times after a whole genome duplication, gene dosage balance constraints and not functional change are the major determinants of gene retention

Régulation et concurrence dans le transport collectif urbain

In Europe, most of the urban public transport services are not operated on a commercial basis. The implication of local public authorities in the sector is important: they organize their local market, they finance services and, sometimes, they also act as producers. This paper analyzes the public transport system in four European cities: Lyon, Stockholm, Helsinki and Brussels and concentrates, in particular, on the introduction of regulated competition. Four different market mechanisms can be used in the public transport sector: (1) competitive tendering, (2) open access with on-track competition, (3) yardstick competition where the operator’s reward is based on a comparative evaluation of its performance and (4) the possibility of challenging the incumbent public operator. The pros and cons of different competitive mechanisms are presented and the article discusses the conditions under which a truly competitive market could be settle

Régulation et concurrence dans le transport collectif urbain

In Europe, most of the urban public transport services are not operated on a commercial basis. The implication of local public authorities in the sector is important: they organize their local market, they finance services and, sometimes, they also act as producers. This paper analyzes the public transport system in four European cities: Lyon, Stockholm, Helsinki and Brussels and concentrates, in particular, on the introduction of regulated competition. Four different market mechanisms can be used in the public transport sector: (1) competitive tendering, (2) open access with on-track competition, (3) yardstick competition where the operator? reward is based on a comparative evaluation of its performance and (4) the possibility of challenging the incumbent public operator. The pros and cons of different competitive mechanisms are presented and the article discusses the conditions under which a truly competitive market could be settled.public transport, regulation, competition

Le jeu sérieux « TrajectStory » : aider les territoires de montagne à trouver leur trajectoire

https://imagine.hypotheses.org/At a time when the CIO has just announced that France will be the next host of the Winter Olympics 2030, what path should future mountain regions take? Sustainable? Resilient? Liveable? To help regions answer this question and move forward with their choices, a serious game was created in 2023 as part of an experimental protocol. It is part of a series of projects: the IMAGINE human and social sciences research project, which continues in the form of two projects supported by Aix-Marseille University: MATMATA funded by ECCOREV, and MEDIALPES funded by the Bourse aux projets de culture scientifique.Alors que le CIO vient d’annoncer que la France serait le prochain terrain des jeux olympiques d’hiver 2030, quelle trajectoire emprunter pour les futurs territoires de montagne? Une trajectoire durable ? résiliente ? vivable ? Pour aider les territoires à répondre à cette question et avancer dans leurs choix, un jeu sérieux faisant parti d’un protocole expérimental a été créé en 2023. Il fait partie d'un cheminement s'insérant dans une continuité de projets : le projet de recherche en sciences humaines et sociales IMAGINE, qui se poursuit sous la forme de deux projets soutenus par Aix-Marseille Université : MATMATA financé par ECCOREV, et MEDIALPES financé par la Bourse aux projets de culture scientifique