Faut-il chauler et fertiliser les prairies permanentes des sols acides et peu fertiles ?

L'intérêt du chaulage dans les prairies permanentes est assez controversé. Un essai de longue durée (prairie permanente sur sol acide semée ensuite en dactyle) procure des informations sur l'effet du chaulage (gain de production, intérêt économique) et pour l'intensification écologique de ces milieux.La réponse au chaulage et à la fertilisation d'une prairie permanente suivie d'une prairie temporaire de dactyle a été étudiée pendant 8 + 4 ans. La production annuelle de la prairie permanente non fertilisée non chaulée (pH 5) est de 1,1 t MS/ha. L'effet du chaulage (+ 0,7 t MS/ha) n'est significatif que sur les parcelles non fertilisées ; l'effet majeur de la fertilisation NPKS (+ 4,0 t MS/ha) est attribué à l'apport de P, limitant dans ce sol. Avec le dactyle (cv. Accord), les effets du chaulage (jusqu'à + 2,7 t MS/ha) et de la fertilisation (jusqu'à + 5,3 t MS/ha) sont supérieurs, la production du traitement fertilisé et chaulé atteignant 9 t MS/ha. Dans ce cas, la fertilisation et le chaulage sont justifiés économiquement et permettent d'utiliser cette parcelle dans un système plus intensif

Re-evaluation of the liming-fertilization interaction in grasslands on poor and acid soils

International audienceThe effect of surface liming on herbage production in permanent grasslands is rather uncertain. To better understand the effect of liming on the grassland, a study was made with a field experiment and a pot experiment with soil from the same field. In the field, the effects of liming and NPK fertilization on the production and composition of the vegetation were studied. In pots, the effects of liming and phosphate fertilization on different grass species were analysed. The effect of NPK fertilization (+3Æ96 t ha)1) on the production of the original grassland was greater than that of liming (+0Æ68 t ha)1),which was only observed (P < 0Æ05) on the unfertilized plots. Liming increased the total number of species and the proportion of dicotyledons. After replacing the semi-natural community with Dactylis glomerata L., the effects of liming (+2Æ37 t ha)1) and fertilization (+6Æ52 t ha)1) were increased. These results, together with those of the pot trial, show the important role of phosphorus in the fertilization effect, and are interpreted as a protective effect of P against aluminium toxicity

Multiple phytochrome-interacting bHLH transcription factors repress premature seedling photomorphogenesis in darkness

[Background]: An important contributing factor to the success of terrestrial flowering plants in colonizing the land was the evolution of a developmental strategy, termed skotomorphogenesis, whereby postgerminative seedlings emerging from buried seed grow vigorously upward in the subterranean darkness toward the soil surface.[Results]: Here we provide genetic evidence that a central component of the mechanism underlying this strategy is the collective repression of premature photomorphogenic development in dark-grown seedlings by several members of the phytochrome (phy)-interacting factor (PIF) subfamily of bHLH transcription factors (PIF1, PIF3, PIF4, and PIF5). Conversely, evidence presented here and elsewhere collectively indicates that a significant component of the mechanism by which light initiates photomorphogenesis upon first exposure of dark-grown seedlings to irradiation involves reversal of this repression by rapid reduction in the abundance of these PIF proteins, through degradation induced by direct interaction of the photoactivated phy molecule with the transcription factors.[Conclusions]: We conclude that bHLH transcription factors PIF1, PIF3, PIF4, and PIF5 act as constitutive repressors of photomorphogenesis in the dark, action that is rapidly abrogated upon light exposure by phy-induced proteolytic degradation of these PIFs, allowing the initiation of photomorphogenesis to occur.This work was supported by a postdoctoral fellowship from the Spanish Ministry of Education and Science to P.L., by a “Ramon y Cajal” contract and a Spanish Ministry of Education and Science Grant BIO2006-09254 to E.M., by a Research Fellowship of the Japan Society for the Promotion of Science for Young Scientists to Y.O., by National Science Foundation Grants IBN-0418653 and IOS-0822811 to E.H., and by National Institutes of Health Grant GM-47475, Department of Energy Grant DEFG03-87ER13742, and USDA Agricultural Research Service Current Research Information System Grant 5335-21000-017-00D to P.H.Q.Peer reviewe

Long Terms Stability and Metastable Behavior of Perovskite Solar Devices on Outdoor Conditions

International audienc

Quality indicators in the treatment of geriatric hip fractures: literature review and expert consensus

PURPOSE Even though hip fracture care pathways have evolved, mortality rates have not improved during the last 20 years. This finding together with the increased frailty of hip fracture patients turned hip fractures into a major public health concern. The corresponding development of an indicator labyrinth for hip fractures and the ongoing practice variance in Europe call for a list of benchmarking indicators that allow for quality improvement initiatives for the rapid recovery of fragile hip fractures (RR-FHF). The purpose of this study was to identify quality indicators that assess the quality of in-hospital care for rapid recovery of fragile hip fracture (RR-FHF). METHODS A literature search and guideline selection was conducted to identify recommendations for RR-FHF. Recommendations were categorized as potential structure, process, and outcome QIs and subdivided in-hospital care treatment topics. A list of structure and process recommendations that belongs to care treatment topics relevant for RR-FHF was used to facilitate extraction of recommendations during a 2-day consensus meeting with experts (n = 15) in hip fracture care across Europe. Participants were instructed to select 5 key recommendations relevant for RR-FHF for each part of the in-hospital care pathway: pre-, intra-, and postoperative care. RESULTS In total, 37 potential QIs for RR-FHF were selected based on a methodology using the combination of high levels of evidence and expert opinion. The set consists of 14 process, 13 structure, and 10 outcome indicators that cover the whole perioperative process of fragile hip fracture care. CONCLUSION We suggest the QIs for RR-FHF to be practice tested and adapted to allow for intra-hospital longitudinal follow-up of the quality of care and for inter-hospital and cross-country benchmarking and quality improvement initiatives

Quality indicators in the treatment of geriatric hip fractures: literature review and expert consensus

Purpose: Even though hip fracture care pathways have evolved, mortality rates have not improved during the last 20 years. This finding together with the increased frailty of hip fracture patients turned hip fractures into a major public health concern. The corresponding development of an indicator labyrinth for hip fractures and the ongoing practice variance in Europe call for a list of benchmarking indicators that allow for quality improvement initiatives for the rapid recovery of fragile hip fractures (RR-FHF). The purpose of this study was to identify quality indicators that assess the quality of in-hospital care for rapid recovery of fragile hip fracture (RR-FHF). Methods: A literature search and guideline selection was conducted to identify recommendations for RR-FHF. Recommendations were categorized as potential structure, process, and outcome QIs and subdivided in-hospital care treatment topics. A list of structure and process recommendations that belongs to care treatment topics relevant for RR-FHF was used to facilitate extraction of recommendations during a 2-day consensus meeting with experts (n = 15) in hip fracture care across Europe. Participants were instructed to select 5 key recommendations relevant for RR-FHF for each part of the in-hospital care pathway: pre-, intra-, and postoperative care. Results In total, 37 potential QIs for RR-FHF were selected based on a methodology using the combination of high levels of evidence and expert opinion. The set consists of 14 process, 13 structure, and 10 outcome indicators that cover the whole perioperative process of fragile hip fracture care. Conclusion: We suggest the QIs for RR-FHF to be practice tested and adapted to allow for intra-hospital longitudinal follow-up of the quality of care and for inter-hospital and cross-country benchmarking and quality improvement initiatives

Fungal septins: one ring to rule it all?

El pdf del artículo es la versión pre-print.Septins are a conserved family of GTP-binding proteins found in living organisms ranging from yeasts to mammals. They are able to polymerize and form hetero-oligomers that assemble into higher-order structures whose detailed molecular architecture has recently been described in different organisms. In Saccharomyces cerevisiae, septins exert numerous functions throughout the cell cycle, serving as scaffolds for many different proteins or as diffusion barriers at the bud neck. In other fungi, septins are required for the proper completion of diverse functions such as polarized growth or pathogenesis. Recent results from several fungi have revealed important differences in septin organization and regulation as compared with S. cerevisiae, especially during Candida albicans hyphal growth and in Ashbya gossypii. Here we focus on these recent findings, their relevance in the biology of these eukaryotes and in consequence the >renaissance> of the study of septin structures in cells showing a different kind of morphological behaviour. © Versita Warsaw and Springer-Verlag Berlin Heidelberg 2009.Peer Reviewe