Arnica montana : évaluation des ressources génétiques françaises en vue du développement de la culture en plaine et en montagne

Ce volume regroupe les textes issus du programme Casdar "Innovation et Partenariat" et "Recherche finalisée et innovation" de 2013. Le colloque de restitution s’est déroulé le 6 février 2019 sous l’égide du GIS Relance AgronomiqueArnica montana is a major medicinal specie, which is now mainly produced from wild harvesting,especially in mainland France. As the wild resource is decreasing, and in order to maintain or even Gourlin L. et al. 68 Innovations Agronomiques 71 (2019), 67-80 develop the French production, cultivation is a good option, that is still very limited, because of its difficulty. Finding the right plant material could help to enhance cultivation programs. This project aimed at growing 24 wild populations, which were collected in mainland France, and to compare them with 2 commercial varieties, ‘Arbo’ and ‘Arnimed’. This was set on 4 experimentation spots, chosen for their potential match for Arnica cultivation. The experiment lasted 3 years, and morphological andagronomical subjects were studied on the populations. Sesquiterpene lactones and flavonoidsanalyzed, and a new methodology of evaluation was developed. The results showed extreme variabilityof phenotypic and chemical expression of the different populations. An important death rate has beennoticed on wild populations, but the causes are still unknown. On the set of variables chosen,commercial varieties ‘Arbo’ and ‘Arnimed’ were particularly competitive, and two wild populations standout with promising results. One seems appropriate for starting selection works on a variety that would besuitable for loaw altitude, and the other one could be a local (French) alternative to the cultivation ofselected varieties (‘Arbo’ and ‘Arnimed’ are from Swiss and German selection work).L’arnica des montagnes est une espèce médicinale importante dont la production est principalementissue de la cueillette à l’état sauvage, notamment sur le territoire métropolitain. La ressource étant enrégression, le maintien, voire le développement de la production française passe donc par la mise enculture, actuellement anecdotique car difficile. Certains freins pourraient être levés par la mise enévidence de matériel végétal adapté à la production. L’objectif de ce projet était de mettre en culture 24populations d’origines sauvages (prospectées en France métropolitaine) et de les comparer à deuxvariétés commerciales témoins ‘Arbo’ et ‘Arnimed’, sur 4 sites d’expérimentation aux contextespédoclimatiques variés mais a priori adaptés à la culture de l’espèce. Durant les 3 années d’essai, unsuivi morphologique et agronomique des populations a été réalisé. Des analyses des sesquiterpèneslactones et flavonoïdes ont été effectuées, et une nouvelle méthodologie de dosage de ces composés aété développée. Les résultats mettent en exergue la forte variabilité de l’expression phénotypique etchimique des différentes souches testées. Une forte mortalité globale a pu être constatée surl’ensemble des populations sauvages étudiées sans que les causes aient pu en être identifiées. Surl’ensemble des variables suivies, les variétés commerciales ‘Arbo’ et ‘Arnimed’ sont particulièrementperformantes, et deux populations sauvages se démarquent par leurs résultats intéressants : l’uneparait pertinente pour démarrer des travaux de sélection d’une variété adaptée à la basse altitude,tandis que l’autre, originaire du Massif central, pourrait se proposer comme une alternative d’originelocale (française) à la culture de variétés commerciales sélectionnées (suisse et allemande)

[Selective activation of blood pressure monitoring alarms: effect of noise pollution in the intensive care unit]

International audienceOBJECTIVE: To evaluate a selective activation of sounding alarms on non-invasive blood pressure (BP) monitoring according to the patient haemodynamic status. STUDY DESIGN: Prospective study. METHODS: Activation of alarms on BP was regulated with a protocol. Sounding alarms were either inactivated when patient's haemodynamic status was stable (group 1), or activated when it was unstable (group 2). The frequency of BP measurement was one every 15 min. For all mean BP value recorded, the following criteria were analyzed: 1) normality of the value compared to ranges 65-115 mmHg in group 1 or compared to alarm thresholds in group 2; 2) consequences on the care and therapeutic; 3) delay when an abnormal value was detected and managed after more than 15 min. RESULTS: 1,674 hours of monitoring from 42 patients, allowed the analysis of 6,695 measurements of mean BP, 3,092 in group 1 and 3,603 in group 2. In group 1, 2,822 measurements were considered as normal and 3,094 measures in group 2. Eight measurements had consequences on therapeutic in group 1, with only one with delay in care giving. 287 measurements had consequences on therapeutic in group 2, 8 with delay in care giving. Six per cent of abnormal measurements in group 2 were managed with delay. This protocol reduced by 52% the production of sounding alarms on BP, without noxious effects for the patients. CONCLUSION: Selective activation of sounding alarms on BP, according to the patient haemodynamic status, reduced noise pollution and could be one solution to improve monitoring efficiency in intensive care unit

Selective and collective actuation in active solids

Active solids consist of elastically coupled out-of-equilibrium units performing work. They are central to autonomous processes, such as locomotion, self-oscillations and rectification, in biological systems,designer materials and robotics. Yet, the feedback mechanism between elastic and active forces, and the possible emergence of collective behaviours in a mechanically stable elastic solid remains elusive. Here we introduce a minimal realization of an active elastic solid, in which we characterize the emergence of selective and collective actuation and fully map out the interplay between activity, elasticity and geometry. Polar active agents exert forces on the nodes of a two dimensional elastic lattice. The resulting displacement field nonlinearly reorients the active agents. For large enough coupling, a collective oscillation of the lattice nodes around their equilibrium position emerges. Only a few elastic modes are actuated and, crucially, they are not necessarily the lowest energy ones. Combining experiments with the numerical and theoretical analysis of an agents model, we unveil the bifurcation scenario and the selection mechanism by which the collective actuation takes place. Our findings may provide a new mechanism for oscillatory dynamics in biological tissues and specifically confluent cell monolayers. The present selection mechanism may also be advantageous in providing meta-materials, with bona fide autonomy.Comment: 6 pages, 4 figure

[Selective activation of blood pressure monitoring alarms: effect of noise pollution in the intensive care unit]

International audienceOBJECTIVE: To evaluate a selective activation of sounding alarms on non-invasive blood pressure (BP) monitoring according to the patient haemodynamic status. STUDY DESIGN: Prospective study. METHODS: Activation of alarms on BP was regulated with a protocol. Sounding alarms were either inactivated when patient's haemodynamic status was stable (group 1), or activated when it was unstable (group 2). The frequency of BP measurement was one every 15 min. For all mean BP value recorded, the following criteria were analyzed: 1) normality of the value compared to ranges 65-115 mmHg in group 1 or compared to alarm thresholds in group 2; 2) consequences on the care and therapeutic; 3) delay when an abnormal value was detected and managed after more than 15 min. RESULTS: 1,674 hours of monitoring from 42 patients, allowed the analysis of 6,695 measurements of mean BP, 3,092 in group 1 and 3,603 in group 2. In group 1, 2,822 measurements were considered as normal and 3,094 measures in group 2. Eight measurements had consequences on therapeutic in group 1, with only one with delay in care giving. 287 measurements had consequences on therapeutic in group 2, 8 with delay in care giving. Six per cent of abnormal measurements in group 2 were managed with delay. This protocol reduced by 52% the production of sounding alarms on BP, without noxious effects for the patients. CONCLUSION: Selective activation of sounding alarms on BP, according to the patient haemodynamic status, reduced noise pollution and could be one solution to improve monitoring efficiency in intensive care unit