TRY plant trait database – enhanced coverage and open access

Plant traits - the morphological, anatomical, physiological, biochemical and phenological characteristics of plants - determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait‐based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits - almost complete coverage for ‘plant growth form’. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait–environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives

Atteintes des cellules hématopoïétiques médullaires au cours de l'infection lentivirale chez le primate (étude des conséquences sur la lymphoïèse T)

CAEN-BU Sciences et STAPS (141182103) / SudocSudocFranceF

Le souterrain de l'âge du fer de Kervéo-en-Plomelin (Finistère)

Giot P R, Ducouret J.-P. Le souterrain de l'âge du fer de Kervéo-en-Plomelin (Finistère). In: Annales de Bretagne. Tome 75, numéro 1, 1968. pp. 101-116

Prévalence du MV2 de la deuxième molaire maxillaire (étude C.B.C.T.)

TOULOUSE3-BU Santé-Centrale (315552105) / SudocSudocFranceF

Effets des médicaments de l'anesthésie sur les propriétés contractiles et electrophysiologiques du myocarde soumis à une ischemie-reperfusion in vitro

CAEN-BU Sciences et STAPS (141182103) / SudocSudocFranceF

Etude inter-tissu et inter-espèce des mécanismes d'action cellulaires et membranaires cardiaques de substances antiarythmiques K+- bloquantes sur tissu sain et en conditions d'ischémie-reperfusion

Le mode d'action des médicaments antiarythmiques de classe III consiste en un blocage des canaux potassiques responsables de la repolarisation du potentiel d'action dans les cellules myocardiques. Ces médicaments se sont révélés efficaces dans le traitement des fibrillations auriculaires. Cependant, leur utilisation est retreinte du fait de leurs propriétés proarythmiques. En effet, ces substances peuvent être à l'origine d'arythmies létales : les torsade-de-pointes dont le mécanisme initiateur correspond, au moins en partie, en l'apparition de postdépolarisations précoces. Le but du travail ici présenté, a été de caractériser cinq médicaments antiarythmiques de classe III capables de bloquer les courants Ikr et/ou Iks en terme de potentialité.1) proarythmique sur un modèle d'induction de postdépolarisations précoces dans les fibres de Purkinje cardiaques isolées de lapin.2) antiarythmique sur un modèle in vitro de myocarde ventriculaire de cobaye soumis à un phénomène d'ischémie-reperfusion.Nous avons ainsi montré que des bloqueurs spécifiques du courant Ikr le dofetilide et le d-sotalol induisent une prolongation importante de la durée du potentiel d'action des fibres de Purkinje de lapin et de l'endocarde ventriculaire de cobaye. Cet effet confère à ce type de substance un risque élevé d'induction de postdépolarisations précoces mais également une efficacité notable dans le traitement des arythmies ventriculaires induites par l'ischémie et la reperfusion. Les bloqueurs spécifiques du courant Iks, le chromanol 293B et le HMR 1556, sont dépourvus d'effets sur le potentiel d'action des fibres de Purkinje de lapin tandis qu'ils allongent modérément la repolarisation des cellules endocardiques de cobaye. Il en résulte un risque proarythmique nul mais également une absence d'effet cardioprotecteur au cours de l'ischémie-reperfusion dans le modèle utilisé. Enfin, l'azimilide, dont la particularité est de bloquer à la fois les courants Ikr et Iks, allonge de façon importante la durée du potentiel d'action dans les deux préparations cellulaires étudiées, du fait de son aptitude à réduire l'amplitude d'Ikr. Ce médicament s'est révélé associé, au cours de notre étude, à un risque proarythmique non négligeable. L'azimilide a également présenté des effets variables au cours de l'ischémie-reperfusion : il prévient l'apparition des arythmies ventriculaires liées à la reperfusion myocardique mais reste sans effet au cours de l'ischémie.CAEN-BU Médecine pharmacie (141182102) / SudocSudocFranceF

Le desflurane, un médicament de l'anesthésie protecteur dans les ischémies cérébrale et cardiaque focales chez le rat in vivo

CAEN-BU Sciences et STAPS (141182103) / SudocSudocFranceF

Re-interpretation of Old Masters’ practices through optical and rheological investigation: The presence of calcite

Lead white, composed of a mixture of cerussite and hydrocerussite (respectively PbCO3and Pb3(CO3)2(OH)2), is often associated in paintings with other white pigments, especially calcite. By combining in-situ analyses with paint reconstructions, we attempt to get a better understanding of the role of this addition of calcite and to investigate how artists may have used it to modify the properties of their paints. Lead-based white pigments of a Dutch 17th-century nuancierhave been analysed as well as historical paintings. Two examples are given: one from a painting by Roger van der Weyden, in the 15th century, and one by Nicolas Poussin, in the 17th century, from specific zones that indicate the addition of calcite. The presence of calcite and pigments enhances both the optical and the rheological properties. Visible reflectance spectroscopy was carried out on pure paints as well as mixtures and indicated an increase in the transparency of the paint mixture in comparison to pure lead white. Rheological measurements also indicated an increase in the elastic and viscous moduli, as well as of the yield stress again in comparison to pure lead white. Calcite could thus have been used to assist in the creation of impasto effects in lead white paint

Electrophysiological effects of azimilide in an in vitro model of simulated-ischemia and reperfusion in guinea-pig ventricular myocardium

There are few investigations on azimilide effects during ischemia/reperfusion. We have therefore investigated low concentrations of azimilide (0.1 and 0.5 mu mol/l) versus Controls on action potential parameters and occurrence of repetitive responses during simulated ischermia and reperfusion. An in vitro model of "border zone" in guinea-pig ventricular myocardium (n = 30) was used. Azimilide 0.5 mu mol/l lengthened action potential duration in normoxic but not in ischemic-like conditions. Therefore an increased dispersion of action potential duration at 90% of repolarization during simulated ischemia in presence of azimilide was seen. Upon reperfusion, both normal and reperfused myocardium. showed azimilide-induced action potential duration increase. There was a neutral effect on the occurrence of arrhythmias during simulated ischemia; however azimilide showed significant (P = 0.033) antiarrhythmic properties following reperfusion. To Mimic I-Kr and I-Ks blocking properties of azimilide we further used dofetilide 10 nmol/l with HMR 1556 1 nmol/l (N = 9), which was accompanied by less severe shortening (P < 0.05) of action potential duration at 90% of repolarization at 30 min of ischemic-like conditions (-43 +/- 9%), as compared with azimilide 0.5 mu mol/l (-64 +/- 5%) but similar to what seen with azimilide 0.1 mu mol/l (-53 +/- 5%) and Controls (-52 +/- 6%). During reperfusion, 2/9 (22%) preparations had sustained activities, which was less than what observed in Controls (5/10, 50%) and with azimilide 0.5 mu mol/l (0/10, 0%), although not statistically different (respectively, P = 0.35 and P = 0.21). Lack versus homogenous class III effects of azimilide in respectively simulated ischemia and reperfusion may explain its different efficacy on arrhythmias, although prevention of reperfusion arrhythmias calls for other than just its I-Kr and I-Ks blocking properties. (c) 2005 Elsevier B.V. All rights reserved

Structural and Rheological Study of a Bis‐urea Based Reversible Polymer in an Apolar Solvent ^\textrm†

International audienceno abstrac