Identifier, détecter et localiser les centralités économiques : une proposition inspirée de l'algorithme DBSCAN

En sciences régionales, la notion de centre(s) revêt une importance capitale pour plusieurs modèles théoriques et cadres conceptuels. Les dynamiques urbaines et locales ont conduit à une multiplication des centres rendant le polycentrisme la norme dans la plupart des aires métropolitaines. Or, la localisation du centre (ou des centres) est souvent postulée comme exogène, déterminée à l’avance. Elle s’avère souvent un intrant nécessaire afin d’identifier les multiples centres. Cette note de recherche propose de développer un algorithme permettant d’identifier, de détecter et de localiser les différents centres à partir d’une typologie issue de critères économiques (unités de logements et commerciales). Afin de présenter son implémentation, deux applications fictives sont développées. Une première sur une ville monocentrique, et une seconde sur une ville polycentrique. Une application empirique permet d’identifier et de localiser les centralités de 31 régions métropolitaines de recensement (RMR) et agglomérations de recensement (AR) du Québec à partir d’information sur les unités d’évaluation contenues dans les rôles d’évaluations municipaux

Specificity of Ocimum basilicum geraniol synthase modified by its expression in different heterologous systems.

International audienceNumerous aromatic plant species produce high levels of monoterpenols, using geranyl diphosphate (GPP) as a precursor. Sweet basil (Ocimum basilicum) geraniol synthase (GES) was used to evaluate the monoterpenol profiles arising from heterologous expressions in various plant models. Grapevine (Vitis vinifera) calli were transformed using Agrobacterium tumefasciens and the plants were regenerated. Thale cress (Arabidopsis thaliana) was transformed using the floral dip method. Tobacco (Nicotiana benthamiana) leaves were agro-infiltrated for transient expression. Although, as expected, geraniol was the main product detected in the leaves, different minor products were observed in these plants (V. vinifera: citronellol and nerol; N. benthamiana: linalool and nerol; A. thaliana: none). O. basilicum GES expression was also carried out with microbial system yeasts (Saccharomyces cerevisiae) and Escherichia coli. These results suggest that the functional properties of a monoterpenol synthase depend not only on the enzyme's amino-acidic sequence, but also on the cellular background. They also suggest that some plant species or microbial expression systems could induce the simultaneous formation of several carbocations, and could thus have a natural tendency to produce a wider spectrum of monoterpenols

Biosynthesis of monoterpene scent compounds in roses

The scent of roses (Rosa x hybrida) is composed of hundreds of volatile molecules.Monoterpenes represent up to 70% percent of the scent content in some cultivars, such asthe Papa Meilland rose. Monoterpene biosynthesis in plants relies on plastid-localizedterpene synthases. Combining transcriptomic and genetic approaches, we show thatthe Nudix hydrolase RhNUDX1, localized in the cytoplasm, is part of a pathway for thebiosynthesis of free monoterpene alcohols that contribute to fragrance in roses. TheRhNUDX1 protein shows geranyl diphosphate diphosphohydrolase activity in vitro andsupports geraniol biosynthesis in planta

Transcarotid Approach for Transcatheter Aortic Valve Replacement With the Sapien 3 Prosthesis

International audienceObjectives: This study sought to describe the procedural and clinical outcomes of patients undergoing transcarotid (TC) transcatheter aortic valve replacement (TAVR) with the Edwards Sapien 3 device.Background: The TC approach for TAVR holds the potential to become the optimal alternative to the transfemoral gold standard. Limited data exist regarding safety and efficacy of TC-TAVR using the Edwards Sapien 3 device.Methods: The French Transcarotid TAVR prospective multicenter registry included patients between 2014 and 2018. Consecutive patients treated in 1 of the 13 participating centers ineligible for transfemoral TAVR were screened for TC-TAVR. Clinical and echocardiographic data were prospectively collected. Perioperative and 30-day outcomes were reported according to the updated Valve Academic Research Consortium (VARC-2).Results: A total of 314 patients were included with a median (interquartile range) age of 83 (78 to 88) years, 63% were males, Society of Thoracic Surgeons mortality risk score 5.8% (4% to 8.3%). Most patients presented with peripheral artery disease (64%). TC-TAVR was performed under general anesthesia in 91% of cases, mostly using the left carotid artery (73.6%) with a procedural success of 97%. Three annulus ruptures were reported, all resulting in patient death. At 30 days, rates of major bleeding, new permanent pacemaker, and stroke or transient ischemic attack were 4.1%, 16%, and 1.6%, respectively. The 30-day mortality was 3.2%.Conclusions: TC-TAVR using the Edwards Sapien 3 device was safe and effective in this prospective multicenter registry. The TC approach might be considered, in selected patients, as the first-line alternative approach for TAVR whenever the transfemoral access is prohibited. Sapien 3 device was safe and effective in our multicenter cohort

Lenalidomide maintenance fails to overcome the unfavourable prognosis of low NK-cell counts in rituximab-chemotherapy responsive elderly DLBCL patients: A LYSA group study

International audienceLow baseline NK-cell counts (NKCCs) in patients with diffuse large B-cell lymphoma (DLBCL) are associated with a poor prognosis. The REMARC phase III trial (NCT01122472) showed that lenalidomide maintenance prolonged PFS in rituximab–chemotherapy responders. We conducted a REMARC ancillary study analysing the impact of lenalidomide maintenance on the prognostic value of low NKCCs. Blood samples from 335 elderly French patients enrolled in the REMARC trial were analysed by flow cytometry to obtain NKCCs at diagnosis (n = 220), at randomization (n = 186) and/or six months after randomization (n = 184). Baseline NKCCs < 100 cells/μl were associated with shorter PFS and OS (HRs = [2.2 (1.4, 3.3), p < 0.001] and [2.8 (1.7, 4.5), p < 0.001], respectively), independently of aaIPI. In a competing risk analysis, low NKCCs at baseline were associated with a higher risk of relapse/progression (p = 0.0025), but not of death without progression (p = 0.33). Lenalidomide did not affect the prognosis value of low baseline NKCCs (p = 0.6349). Similar results were obtained for low NKCCs at randomization. Our results demonstrate that low NKCCs at baseline and post rituximab–chemotherapy are robust prognostic factors in DLBCL and reveal that lenalidomide has no impact on this parameter. Other therapeutic strategies aiming at improving NK-cell function could improve outcomes in DLBCL

Ecrivains-cinéastes

Dans le dialogue entre arts, rares sont les créateurs appartenant à égalité à deux sphères différentes. Dans les années 1930, des dramaturges (Pagnol, Guitry) et des romanciers (Giono, Malraux) développent une double compétence, puis dans les années 1960 Marguerite Duras et Alain Robbe-Grillet (sous la tutelle d’Alain Resnais) amorcent un processus de fusion entre les genres ou les pratiques. Les années 2000 constituent-elles un nouvel âge d’or des rapports entre littérature et cinéma ? Et dans quelle mesure ce temps s’inscrit-il dans le paysage européen ? Les contributeurs de ce numéro feront apparaître la complexité de l’œuvre des principaux représentants de ce renouveau : des cinéastes passant à l’écriture (Catherine Breillat, Paul Vecchiali, Christophe Honoré ; Dai Sijie, Éric Rohmer, Jean-Luc Godard) ; des écrivains passant à la réalisation (Jean-Philippe Toussaint, Virginie Despentes, Philippe Claudel, Camille de Toledo, Eugène Green) ; des auteurs de BD se tournant vers le 7e art (Schuiten et Peeters, Enki Bilal) ; des croisements entre arts plastiques et vidéo (Sophie Calle, Valérie Mréjen) ; des cinéastes ou acteurs publiant leurs scénarios ou leurs essais critiques ; des auteurs mêlant littérature, documentaires et écriture de scénarios (Jérôme Prieur, Jérôme Beaujour)