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International audience; Axillary bud outgrowth is a major process allowing the plant to adapt its architecture to environmental constraints. Indeed, the dormant buds formed at each leaf axil contain meristems, which depending on the environment, remain quiescent or resume activity leading to bud outgrowth and the development of a new axis [1]. Studies on apical dominance, i.e. the inhibition of buds by the growing apical zone, have highlighted the opposite roles of auxin and sugar, which is involved in a signaling and trophic regulation of bud activity [2-4]. However, understanding the interaction between the environment and the mechanisms of apical dominance is a major issue [3]. Our study tests the long-standing hypothesis that sugar availability is involved in the mediation of light effect on bud outgrowth at plant-level. We combined experimental studies and computer simulations, using rose as a plant model. First, using buds grown in vitro, high sugar availability was demonstrated to reduce auxin repressing effect on bud outgrowth, indicating that it could reduce the auxin-related apical dominance in planta. Sugar effect was highlighted to be due to a repression of a pathway downstream of auxin by testing different possible scenarios in a model [5]. Then, we demonstrated the ability of sugar availability to modulate bud outgrowth rate and to explain, at least partly, light effect in planta. Plants were grown under comfort light conditions, or under permanent or temporary light limitation. Physiological and morphological analyses showed a positive relationship between bud outgrowth rate and sugar contents in stems. Moreover, the exogenous supply of sugar stimulated bud outgrowth under unfavorable light conditions. Calculating photosynthesis and carbohydrate (C) demand highlighted that, compared to high light, continuous and temporary low light altered sugar contents through a predominant effect on photosynthesis and on C demand, respectively. These results highlight that light, by controlling C sources and sinks, modulates the availability of sugar for buds and thus the repressive effect of auxin on axillary bud activity. They pave the way for a better consideration of the mechanisms controlling the control of lateral meristems in plant models.

International audience

International audience; Branching is a major agronomic variable determining yield and quality, and is very sensitive to environmental conditions. Previous studies on rose showed that a continuous high light intensity perceived during the bud outgrowth period stimulated bud outgrowth compared to a continuous low light intensity. This effect was related to higher cytokinin contents in the nodes. Interestingly, a temporary light intensity restriction applied before the bud outgrowth period over-stimulated bud outgrowth, but the mechanisms involved remain unknown. In this case, we assume a nonlimitation in cytokinins because of the current high light intensity during the bud outgrowth period, but an increase in sugars that would explain bud outgrowth stimulation. To test sugar involvement, we quantified bud outgrowth, sugar contents, and the balance between sources and sinks for sugars in the bud outgrowth period of plants grown under either continuous high light intensity or under a temporary light restriction followed by a high light intensity. In addition, we quantified the effect of exogenous sugar supply on bud outgrowth for plants under continuous high light intensity, and the effect of leaf masking under the non-continuous treatment. Our results showed that after a temporary light intensity restriction and return to high light intensity, sugars accumulated compared to a continuous high light intensity. Furthermore, the growth of apical organs was reduced indicating that sugar accumulation might be due to a higher balance between sources and sinks for sugars. Exogenous sucrose supply through the petiole of intact plants grown under high light intensity stimulated bud outgrowth. Conversely, leaf masking after a temporary light intensity restriction inhibited bud outgrowth. This supports that sugar accumulation is an important trigger of bud outgrowth after a temporary light intensity restriction. Together these results indicate that an anterior low light intensity applied during the main stem development reduces growth of apical organs while higher sugar availability afterward favors lateral bud outgrowth.

Identifying and quantifying future climate impacts on water resources has major economic and societal implications, rendering such studies extremely important for water planners. In this research, we integrate the outputs of the general global models GDFL-ESM2M (the suitable one of the three studied models; CNRM-CM5, GFDL-ESM2M and EC-EARTH) downscaled by regional climate model (RCA4) under representative concentration pathways RCPs scenarios 8.5, into two hydrological models to provide approximations of climate change impacts on water quantity and quality in El Sheikh Zuwaid-Rafah quaternary aquifer system which is the main source of water in the area. The projected changes of the rising scenario between the periods 1980-2005 and 2050-2075 from the three studied GCMs predicted an increase in the mean of July temperature between 4.2 - 4.8 K (kelvin degree), whereas January temperature was estimated to increase between 1.8 - 5.4 K (kelvin degree). The cumulative annual precipitation was estimated to decrease by a range varied between 30% to 51%. A Simple Bias correction (SBC) technique was implemented to correct the simulated monthly precipitation series of RCA4 (GDFL-ESM2M) over Sinai Peninsula. A three dimensional finite difference flow model (Processing MODFLOW -PM5), and the implemented solute transport model (MT3D) were used to predict the groundwater and the total dissolved solids storage. Results from running the raising scenario RCP 8.5 estimated that by the hydrological year 2074 groundwater recharge would be decreased by 2.73 M.m3, leading with the yearly exploitation to decrease groundwater storage to 11.83 M.m3 and decrease in dissolve salt storage 33.1 M. Kg.

Huge amounts of geospatial data have been made freely available recently on the Web. For example, maps from geospatial search engines like Google Maps, images from satellites, open geospatial data from national cartographic agencies and user-contributed geospatial content from social networks. This article surveys the state of the art in the area of linked geospatial data, i.e., geospatial data made available on the Web using linked data technologies such as RDF and SPARQL, and interlinked with other Web data to increase its value for users and applications.

OBJECTIVE: To assess and compare, according to Beers and STOPP criteria, the frequency and causes of potentially inappropriate medications (PIMs) in elderly, as well as the relationship between PIMs use and patient's treatment satisfaction, evaluated using the Treatment Satisfaction Questionnaire for Medications (TSQM). METHOD: 350 patients (mean age=73.49 years), taking a total of 1893 medications, were enrolled from community pharmacies. RESULTS: 6.2% and 20.4% of the medications were inappropriate according to the STOPP and Beers lists respectively; 103 (29.4%) and 210 (60%) patients had at least one PIM according to STOPP and Beers criteria respectively. The most common cause of PIM was a full dose of proton pomp inhibitor for >8 weeks (STOPP) and using a drug that exacerbates/causes syndrome of inappropriate antidiuretic hormone secretion (Beers). The number of medications taken by the participant, advanced age, female gender, prescription of medications for anxiety/depression, ulcers/gastroesophageal reflux, rheumatoid arthritis and epilepsy significantly increased the PIMs number. When using STOPP criteria, all TSQM subscale scores were significantly lower among patients with PIM use compared to those without PIM. The same trend was observed for Beers critertia, with a significant difference reached for side effects and convenience subscales only. CONCLUSION: Selecting the appropriate tools to assess PIMs, prescribers and patient education regarding the risks associated with PIMs, and patient's perception and satisfaction regarding his treatment, are critical issues to be addressed among older adults.

Given a graph, an index is a data structure supporting a map from a collection of keys to a collection of elements in the graph. For example, we may have an index on node labels, which, given a node label as search key, facilitates accelerated access to all nodes of the graph having the given label. The evaluation of queries on graph databases is often facilitated by index data structures. An index can be the primary representation of the graph or can be a secondary access path to elements of the graph.