Le Maroc truffier: la répartition géographique des truffes et truffes du désert et leur productivité

Truffles are an important natural resource for the rural economy in Morocco and can play an important role in relieving pressure on forest and pastoral resources. However, there is a lack of knowledge of their geographical distribution and as well as their productivity. A documentary analysis, field surveys, interviews and workshops with resource persons and forest and agricultural managers across the country have made it possible to draw up an inventory of existing species, their geographical distribution maps and productivity. Morocco has ten species of desert truffles of the genera Terfezia, Tirmania, Delastria, Picoa and Tuber, widespread in four main truffle areas: the forest of Maâmora, the Sahel of Doukkala-Abda, the North-East region and the Moroccan Sahara. Productivities are also variable between zones and within zones. They are influenced by the nature of the soil and the distribution of precipitation. The results obtained in cartographic form, a map of the geographical distribution of truffles and a productivity map, constitute a first step towards understanding the truffle potential and improving decision-making for the valuation of Moroccan truffles.  Keywords: Truffles, Desert truffles, Truffle areas, Oriental, Maâmora, Doukkala-Abda, Sahara, Morocco truffleLes truffes constituent au Maroc une ressource naturelle importante pour l’économie rurale et peuvent jouer un rôle important dans l’allégement de la pression sur les ressources forestières et pastorales. Cependant, on note un manque de connaissance de leur répartition géographique et moins encore de leur productivité. Une analyse documentaire, des prospections de terrain, des interviews et des ateliers avec des personnes ressources et des gestionnaires forestiers et d’agriculture à l’échelle du pays ont permis la réalisation d’un inventaire des espèces existantes, de leurs cartes de répartition géographique et de productivité. Le Maroc compte une dizaine d’espèces des truffes de désert des genres Terfezia, Tirmania, Delastria, Picoa et Tuber, répandues dans quatre principales zones trufficoles : la région Nord-Est, la forêt de la Maâmora, le Sahel Doukkala-Abda et le Sahara marocain. Les productivités sont variables entre les zones et à l’intérieur des zones. Elles sont influencées par la nature des sols et la répartition des précipitations.  Les résultats obtenus sous forme cartographique, une carte de répartition géographique des truffes et une carte de productivité, constituent un premier pas vers la connaissance du potentiel truffier et l’amélioration de la prise de décision pour la valorisation des truffes marocaines. Mots-clés : Truffes, Truffes du désert, Zones trufficoles, Oriental, Maâmora, Sahel Doukkala-Abda, Sahara, Maroc truffie

CAR T cell therapy in B-cell acute lymphoblastic leukaemia: Insights from mathematical models

Immunotherapies use components of the patient immune system to selectively target cancer cells. The use of CAR T cells to treat B-cell malignancies --leukaemias and lymphomas-- is one of the most successful examples, with many patients experiencing long-lasting complete responses to this therapy. This treatment works by extracting the patient's T cells and adding them the CAR group, which enables them to recognize and target cells carrying the antigen CD19+, that is expressed in these haematological tumors. Here we put forward a mathematical model describing the time response of leukaemias to the injection of CAR T-cells. The model accounts for mature and progenitor B-cells, tumor cells, CAR T cells and side effects by incorporating the main biological processes involved. The model explains the early post-injection dynamics of the different compartments and the fact that the number of CAR T cells injected does not critically affect the treatment outcome. An explicit formula is found that provides the maximum CAR T cell expansion in-vivo and the severity of side effects. Our mathematical model captures other known features of the response to this immunotherapy. It also predicts that CD19+ tumor relapses could be the result of the competition between tumor and CAR T cells analogous to predator-prey dynamics. We discuss this fact on the light of available evidences and the possibility of controlling relapses by early re-challenging of the tumor with stored CAR T cells

Multiobjective approach in the treatment of cancer

In this work we deal with a cancer problem involving the growth of tumor cells and their interaction with effector cells. The goal is to find an optimal control minimizing tumor cells density together with the amount of chemotherapy drugs and maximizing the density of effector cells. By invoking the multi-objective optimization we characterize optimal Pareto solutions and give simulation of Pareto front

Lithological discrimination and mineralogical mapping using Landsat-8 OLI and ASTER remote sensing data: Igoudrane region, jbel saghro, Anti Atlas, Morocco

This study aims to delineate the lithological formations, in addition to a mineralogical mapping comparing between the ASTER and Landsat-8 OLI sensors in the Igoudrane region. The research was accomplished using BR along with spectral profiles of minerals, PCA, MNF, ICA, XRD, and reflectance spectrometry. The BR measured with ASTER revealed the presence of amphibole, illite, smectite, muscovite, phengite, basic degree index SiO2, calcite, chlorite, epidote, dolomite, hydroxides, and ferrous silicates. Furthermore, Landsat-8 OLI BR highlighted areas with oxides, hydroxides, and laterite. The spectral profiles of minerals showed their absorption in the VNIR and SWIR regions. The muscovite and illite (phyllic alteration) are distinguished by Al–OH absorption at 2.20 μm. The argillitic alteration is additionally defined by muscovite, illite, and Kaolinite, where Kaolinite has a high absorption at 0.9 μm. Chlorite and carbonates characterized the propylitic alteration zone, with an absorption ranging between 2.3 μm and 2.35 μm due to CO3 and Mg–OH compositions. The oxidation (hematite and jarosite) was distinguished by absorption near 0.95 μm and 2.3 μm, respectively, whereas the goethite spectral profile exhibits absorption near 1.4 μm and 2.2 μm. The absorption of smectite is 1.4 μm, near 2.2 μm. The amphibole had absorption near 1.4 μm and 2.3 μm, whereas the pyroxene had absorption near 1.4 μm and 2.3 μm. The first three components of PCA, MNF, and ICA showed the highest eigenvalues and gave an appreciable discrimination of the lithologies, especially with ASTER. Moreover, the XRD quantified the mineralogy of the rocks, which were compared to the BR of ASTER. The reflectance spectrometry also provided alteration minerals, such as muscovite, phengite, illite, Fe–Mg chlorite, Fe-chlorite, iron oxides, hydroxides, hornblende, and calcite. Overall, the methodology adopted has shown great performance and strong potential for mapping alteration areas and lithological discrimination in similar arid regions