46 research outputs found
Un outil de simulation adapté à la gestion des ressources en eau du territoire dans le cadre d’une démarche participative
National audienceThis paper presents a simulation tool adapted to water resources management on a territorial scale, as part of a participatory process. This tool combines the PILOTE-TER crop model and the Olympe technico-economical simulator. PILOTE-TER links the crop model Pilote developed by Irstea with a database managed through a graphical interface. It makes possible to use the Pilote model to evaluate the water demand and the crop yield at the scale of the field, the farm and the territory. The parameters of the model come from the results of experiments performed by Irstea. PILOTE-TER is linked to the technico-economic simulator Olympe (from INRA) to produce economical indicators. These tools are used for a territorial representation of agriculture build with local stakeholders, allowing the comparison of several scenarios (based on economical, policy or climate changes).Cet article présente un outil de simulation adapté à la gestion de ressources en eau à l’échelle d’un territoire dans le cadre de démarches participatives. Cet outil associe un modèle de culture, Pilote Ter, et le simulateur technico-économique Olympe. Pilote Ter intègre le modèle de culture Pilote développé par Irstea et un système de base de données géré à partir d’une interface graphique. Il permet une utilisation territorialisée du modèle de culture Pilote pour évaluer la demande en eau agricole et les rendements des cultures à l’échelle de la parcelle, de l’exploitation agricole et du territoire. Le paramétrage du modèle s’appuie sur les résultats des expérimentations menées par Irstea. Pilote Ter est couplé au simulateur technico-économique Olympe (INRA) pour produire des indicateurs économiques. Ces deux logiciels sont le support d’une représentation de l’agriculture du territoire co-construite avec les acteurs locaux permettant l’étude de scénarios économiques, réglementaires ou climatiques
Estimating the furrow infiltration characteristic from a single advance point
Management and control of surface irrigation, in particular furrow irrigation, is limited by spatio-temporal soil infiltration variability as well as the high cost and time associated with collecting intensive field data for estimation of the infiltration characteristics. Recent work has proposed scaling the commonly used infiltration function by using a model infiltration curve and a single advance point for every other furrow in an irrigation event. Scaling factors were calculated for a series of furrows at two sites and at four points down the length of the field (0.25 L, 0.5 L, 0.75 L and L). Differences in the value of the scaling factor with distance were found to be a function of the shape of the advance curves. It is concluded that use of points early in the advance results in a substantial loss of accuracy and should be avoided. The scaling factor was also strongly correlated with the furrow-wetted perimeter suggesting that the scaling is an appropriate way of both predicting and accommodating the effect of the hydraulic variability
Synthesis, Molecular Editing, and Biological Assessment of the Potent Cytotoxin Leiodermatolide
It was by way of total synthesis that the issues concerning the stereostructure of leiodermatolide (1) have recently been solved; with the target now being unambiguously defined, the mission of synthesis changes as to secure a meaningful supply of this exceedingly scarce natural product derived from a deep-sea sponge. To this end, a scalable route of 19 steps (longest linear sequence) has been developed, which features a catalytic asymmetric propargylation of a highly enolizable β-keto-lactone, a ring closing alkyne metathesis and a modified Stille coupling as the key transformations. Deliberate digression from this robust blueprint brought a first set of analogues into reach, which allowed the lead qualities of 1 to be assessed. The acquired biodata show that 1 is a potent cytotoxin in human tumor cell proliferation assays, distinguished by GI50 values in the ≤3 nM range even for cell lines expressing the Pgp efflux transporter. Studies with human U2OS cells revealed that 1 causes mitotic arrest, micronucleus induction, centrosome amplification and tubulin disruption, even though no evidence for direct tubulin binding has been found in cell-free assays; moreover, the compound does not seem to act through kinase inhibition. Indirect evidence points at centrosome declustering as a possible mechanism of action, which provides a potentially rewarding outlook in that centrosome declustering agents hold promise of being inherently selective for malignant over healthy human tissue
Disentangling the complexity of groundwater dependent social-ecological systems
Groundwater resources are part of larger social-ecological systems. In this chapter, we review the various dimensions of these complex systems in order to uncover the diversity of elements at stake in the evolution of an aquifer and the loci for possible actions to control its dynamics. Two case studies illustrate how the state of an aquifer is embedded in a web of biophysical and sociopolitical processes. We propose here a holistic view through an IGM-scape that describes the various possible pathways of evolution for a groundwater related social-ecological system. Then we describe the elements of this IGM-scape starting with physical entities and processes, including relations with surface water and quality issues. Interactions with society bring an additional layer of considerations, including decisions on groundwater abstraction, land use changes and even energy related choices. Finally we point out the policy levers for groundwater management and their possible consequences for an aquifer, taking into account the complexity of pathways opened by these levers
Allogeneic stem cell transplantation in second complete remission for core binding factor acute myeloid leukemia: a study from the Acute Leukemia Working Party of the European Society for Blood and Marrow Transplantation
Core binding factor acute myeloid leukemia (AML) comprises two
subtypes with distinct cytogenetic abnormalities of either
t(8;21)(q22;q22) or inv(16)(p13q22)/t(16;16)(p13;q22). Since longterm response to chemotherapy in these leukemias is relatively good,
allogeneic hematopoietic stem cell transplantation is considered in
patients who relapse and achieve second complete remission. To evaluate the outcomes of allogeneic transplantation in this indication, we
studied 631 patients reported to the European Society for Blood and
Marrow Transplantation Registry between the years 2000 and 2014.
Leukemia-free survival probabilities at two and five years were 59.1%
and 54.1%, while overall survival probabilities were 65% and 58.2%,
respectively. The incidence of relapse and risk of non-relapse mortality at
the same time points were 19.8% and 22.5% for relapse and 20.9% and
23.3% for non-relapse mortality, respectively. The most important
adverse factors influencing leukemia-free and overall survival were:
leukemia with t(8;21), presence of three or more additional chromosomal
abnormalities, and Karnofsky performance score <80. Relapse risk was
increased in t(8;21) leukemia and associated with additional cytogenetic
abnormalities as well as reduced intensity conditioning. Measurable
residual disease in molecular evaluation before transplantation was associated with increased risk of relapse and inferior leukemia-free survival
Using a furrow system for surface drainage under unsteady rain
Water excess during winter limits crop development on heavy clay soil conditions of the Gharb valley (Morocco). The furrow system to eliminate these negative effects is the adopted solution. This article focuses on the development of a water transfer model through a furrow system during unsteady rainfall event to evaluate the runoff volume resulting from a reference rainy event. This model contains a production function associated to a transfer function. The production function is based on the Green-Ampt infiltration equation. The latter has been adapted to account for unsteady rain conditions and rainfall intermittence. The transfer function is based on the kinematic wave model, the explicit solution of which is coupled with the water excess generated by the production function. Simulated runoff in the furrows is collected by a drainage ditch evacuating the flow outside a plot of 1.3 ha. The similarity between parameters of a furrow irrigation model and those of the production function is advantageously used for model calibration. The proposed modelling approach shows capabilities to predict water amount and peak discharges evacuated from a plot of around I ha by a furrow system under unsteady rainfall events. As an application, it is used to evaluate the ability of the surface drainage system to evacuate the excessive volumes of water under typical rainfalls