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En matière de Gestion des Ressources En Eau, il devient de plus en plus nécessaire de remonter à l'information pluviométrique. La modélisation est devenue ainsi un outil incontournable. Les modèles hydrologiques reposent sur le cycle hydrologique. Ils transforment les pluies en débits sur le réseau hydrographique. L'objectif de cet article est de décrire le fonctionnement hydrologique du bassin versant du Bafing (principal affluent amont du fleuve Sénégal) en amont de Bafing Makana. Le modèle hydrologique semi distribué à base physique SWAT a été choisi comme modèle de base pour calculer les hydrogrammes de crue à la station de Bafing Makana qui contrôle les entrées au barrage de Manantali. Pour représenter la topographie de la zone d'étude, un MNT de résolution 12.5 m×12.5 m a été retenu. Les observations de pluies et débits sur la période 1979–1986 (pour le calage) et 1988–1994 (pour la validation) ont été utilisées comme entrées. L'analyse de sensibilité a permis de faire apparaître les paramètres les plus significatifs du modèle. Les valeurs de ces paramètres ont été déterminées dans la phase calage puis validées dans la phase validation. La valeur du critère de Nash est de 0.71 pour la phase de calage et de 0.65 pour la phase de validation. Les résultats validés à partir du critère de Nash montrent que les valeurs prises par le critère entrent dans l'intervalle des valeurs satisfaisantes retenues pour ce critère. L'ensemble des résultats obtenus montre que le modèle hydrologique SWAT peut être utilisé dans la gestion du barrage de Manantali à l'horizon 2090.

This abstract the first results of a Phd ongoing work on the impact of climate change and land use land cover on the hydrological dams in a large, transboundary, West-African watershed: The Senegal River Watershed.Freshwater - a fragile resource - is essential for life, development, and the environment. Flowing through Guinea, Mali, Senegal and Mauritania, the Senegal River (fig 1) is a strategic water resource for the West-Africa region and riparian countries development. The Senegal River's water management in time and space is possible thanks to the existing and planned hydroelectric dams built along the river. These water developments aim to meet the growing water, food and energy needs of the member states (Senegal, Mali, Guinea, Mauritania). Access to energy and food security will be a significant challenge in the future due to population growth and climate change. In the coming decades, climate change and changes in land use and land cover will further increase the constraints on the already scarce water resources in the Sudano-Sahelian zone of West Africa.This study is part of the Nexus "Climate change, LULC change, Water, Energy" in the Senegal River basin. The objective is to assess the impact of climate change and land use/land cover on water resources in the upper Senegal River basin and associated socio-economic activities (energy, agriculture, flood support, flood control) for the time horizon 2050. This study aims to develop simulations of streamflow and water storage under assumptions of LULC and climate change for integrated management of dams in a multiple-use context.Our methodology is based on A multi-model approach including a climate model, a land use/land cover forecasting model (land change modeler) for modelling and elaborating future land use/land cover maps (2050) based on past trends (1986, 2006 and 2020) of LULC map, a hydrological model (Swim) for modelling runoff and projecting flows to 2050, and a reservoir management model (Simulsen) for simulating dam management.In this presentation or poster, we will present the elaboration of future LULC maps based on past trends and the reanalyzes of climatic data.

Це дослідження є внеском у наукову літературу про релігійні взаємні інвестиційні фонди, пропонуючи порівняльне дослідження чутливості ефективності ісламських і звичайних фондів до змін у списку сімнадцяти відповідних атрибутів фондів, усі в контексті саудівського ринку. Досліджуваними показниками ефективності є надлишкова віддача, вибірковість і час. Дослідження проводилося з 2011 по 2015 роки з вибіркою 200 активних саудівських фондів, 137 ісламських і 63 звичайних. Висновки показали, що розмір фонду, комісія за управління, співвідношення готівки та ціна-прибуток не мають значення як для ісламських, так і для традиційних фондів. Крім того, ми помітили схожість у чутливості як ісламських, так і звичайних фондів до обороту, несистематичних ризиків, цільового інвестування, минулих показників, віку та перебування в управлінні. Однак вони по-різному реагують на зміну співвідношення ціни та балансу. З іншого боку, систематичний ризик фонду, відношення грошових потоків до балансу та фактори віри є виключно актуальними для ісламських фондів, тоді як зростання фонду та ціль впливають лише на показники традиційного фонду. Нарешті, вибірковість і терміни виявляються взаємовиключними, що свідчить про спеціалізацію управління. Ця робота є першим порівняльним аналізом такого роду. Більша багаторегіональна вибірка та довший період дослідження дадуть кращу інформацію. This study contributes to the academic literature on faith-based mutual funds, by offering a comparative investigation of Islamic vs. conventional funds’ performance sensitivity to changes in a list of seventeen relevant funds’ attributes, all in the context of the Saudi market. The performance measures investigated are the excess return, selectivity and timing. The study took place from 2011 to 2015, with a sample of 200 Active Saudi funds, 137 Islamic and 63 conventional. Findings indicated that fund size, management fees, expense ratio cash and price-earnings ratio were irrelevant to both Islamic and conventional fund performances. In addition, we noticed similarities in both Islamic and conventional funds’ performances sensitivities towards turnover, unsystematic risk, investment target, past performance, age and management tenure. They however react differently towards a change in the price-to-book ratio. On the other hand, fund systematic risk, cashflow-to-book ratio and faith factors are exclusively relevant to Islamic funds, while fund growth and objective only affect conventional fund performance. Finally, selectivity and timing appear to be mutually exclusive, suggesting management specialization. This work appears to be the first comparative analysis of its kind. A larger, multi-regional sample, and a longer study period will provide better insights.

La gestion unilatérale des aires protégées reste l’un des problèmes majeurs des pays subsahariens. Au Togo, les autorités se sont engagées à mettre les populations au centre de tout projet de restauration et de gestion des paysages forestiers. Les populations de la commune 3 dans la préfecture de la Kéran, ne sont pas épargnées. Cette étude a pour objectif d’analyser l’approche participative des populations dans la restauration et la gestion durable de la forêt classée de Wartema. La méthodologique est basée sur la collecte des données à partir d’un questionnaire administré à 85 ménages. Des entretiens ont été menés auprès de 15 individus comprenant des agents des différents services techniques, des agents de la mairie et des personnes ressources. Les données collectées ont été traitées au moyen du logiciel sphinx et Word 2010. Les tableaux, les figures ont été faits au moyen du logiciel Excel 2010 et les cartes réalisées au logiciel Arc GIS pro 3. 10. Il résulte de cette étude que de 1990 à 2020, le taux de couverture évalué à 80% a baissé de 18% ; soit une perte de 275, 6 hectares. Plus de 80% de la forêt a été complètement dévastée. Les associations villageoises de gestion des Aires Protégées (AP) ont été mises en place dans la zone d’étude afin de garder une communication effective entre l'administration des AP et les communautés locales.

The Sahelian regions have experienced a drought that has made them vulnerable to hydro-climatic conditions. Strategies have been developed to reduce this vulnerability. The governments of Senegal, Mauritania, Mali and Guinea have created the Organization for the development of the Senegal River (OMVS in french) with the aim of realizing large hydraulic installations. This resulted in the construction of the Diama and Manantali dams in the Senegal River Basin. The first aims to stop the saline intrusion, the second to regulate the flow of the river, to allow the irrigation of agricultural perimeters, and to produce electrical energy. The impoundment of the Diama dam has modified the hydraulic behavior of the estuary. The purpose of this study is to carry out the hydraulic modeling of the estuary of Senegal river downstream of the Diama Dam in transient mode by the HEC-RAS software. Two geometric models were constructed on the basis of a digital terrain model (DTM) using the Arc-GIS and HEC GeoRAS soft wares after processing the collected topographic data. The first geometric model, of which the areas of Senegal river downstream Diama Dam have been represented by cross-section, is one-dimensional. The second one is also one dimensional; in this model, the area of the Senegal River estuary downstream Diama Dam is introduced as water storage zones. The components of these models are the stream sections, lateral links, and storage areas. The flood hydrograph downstream Diama Dam is introduced as conditions at the upstream limits of the models while the tidal is introduced as a downstream condition. After the stability and calibration, the results given by HEC-RAS simulations are the variations of the water levels, the temporal variations of the flow rates for each section, the maximum flow velocities and the propagation times of the flood waves. The analysis and comparisons of these results strongly suggest using HEC-RAS issues as a decision-making tool helping to manage floods during times of crisis.

Management of reservoir water resources requires the knowledge of flow inputs in this reservoir. Hydrological rainfall-runoff model is used for this purpose. There are several types of hydrological model according the description of the hydrological processes: black-box models, conceptual models, deterministic physical based model. SWAT is a semi-distributed hydrological model designed for water quality and quantity. This versatile tool has been used all around the world to assess and manage water resources. The main objective of the paper is to calibrate and validate the SWAT model on the watershed of Bafing located between 10°30' and 12°30' north latitude and between 12°30' and 9°30' west longitude to assess climate change on this river flows. A DEM with a resolution of 12.5 m × 12.5 m, the daily average flows and the daily observed precipitations on the period 1979-1986 (long period) are used as inputs for the calibration, while precipitations for the period 1988-1994 are used for the validation. The sensitivity analysis was done to detect the most determining coefficients during the calibration step. It shows that 19 parameters are required. Then, the effect of the period on the parameters calibration is checked by considering first the whole period of study and then each year of the period of study. The Nash criterion was used to compare the calculated and the observed hygrographs in each case. The results showed that the longer is the period of calibration, the more accurate is the Nash criterion. The calibration per year gave a best Nash criterion except for a single year. During the validation, the parameters calculated on the long period lead to the best Nash criterion. The values of the Nash criterion calibration and validation are very suitable. These results of calibration can be used to study the long-term evolution of flow at Senegal River on Bafing Makana.

International audience; Dysregulation of the proteolytic balance is often associated with diseases. Serine proteases and matrix metalloproteases are involved in a multitude of biological processes and notably in the inflammatory response. Within the framework of digestive inflammation, several studies have stressed the role of serine proteases and matrix metalloproteases (MMPs) as key actors in its pathogenesis and pointed to the unbalance between these proteases and their respective inhibitors. Substantial efforts have been made in developing new inhibitors, some of which have reached clinical trial phases, notwithstanding that unwanted side effects remain a major issue. However, studies on the proteolytic imbalance and inhibitors conception are directed toward host serine/MMPs proteases revealing a hitherto overlooked factor, the potential contribution of their bacterial counterpart. In this review, we highlight the role of proteolytic imbalance in human digestive inflammation focusing on serine proteases and MMPs and their respective inhibitors considering both host and bacterial origin.

Superior electrostatic control of 2D-FETs enables continued logic power-performance-area (PPA) scaling beyond the 2nm node. Here, we show that WS 2 -based 2D devices give ~40% inverter performance boost against Si at imec 2nm node, using a process-aware DTCO approach. The DTCO is conducted based on an ab-initio calibrated, physical compact model while area scaling is based on contacted gate pitch scaling. Side contacted source/drain, vertically-stacked 2D sheets and fork-sheet architecture are highlighted as key enablers of 2D-FET technology for multiple advanced nodes, using experimentally realistic mobility and Schottky barrier height conditions.

Accurate monitoring of surface water bodies is essential in numerous hydrological and agricultural applications. Combining imagery from multiple sensors can improve long-term monitoring; however, the benefits derived from each sensor and the methods to automate long-term water mapping must be better understood across varying periods and in heterogeneous water environments. All available observations from Landsat 7, Landsat 8, Sentinel-2 and MODIS over 1999–2019 are processed in Google Earth Engines to evaluate and compare the benefits of single and multi-sensor approaches in long-term water monitoring of temporary water bodies, against extensive ground truth data from the Senegal River floodplain. Otsu automatic thresholding is compared with default thresholds and site-specific calibrated thresholds to improve Modified Normalized Difference Water Index (MNDWI) classification accuracy. Otsu thresholding leads to the lowest Root Mean Squared Error (RMSE) and high overall accuracies on selected Sentinel-2 and Landsat 8 images, but performance declines when applied to long-term monitoring compared to default or site-specific thresholds. On MODIS imagery, calibrated thresholds are crucial to improve classification in heterogeneous water environments, and results highlight excellent accuracies even in small (19 km2) water bodies despite the 500 m spatial resolution. Over 1999–2019, MODIS observations reduce average daily RMSE by 48% compared to the full Landsat 7 and 8 archive and by 51% compared to the published Global Surface Water datasets. Results reveal the need to integrate coarser MODIS observations in regional and global long-term surface water datasets, to accurately capture flood dynamics, overlooked by the full Landsat time series before 2013. From 2013, the Landsat 7 and Landsat 8 constellation becomes sufficient, and integrating MODIS observations degrades performance marginally. Combining Landsat and Sentinel-2 yields modest improvements after 2015. These results have important implications to guide the development of multi-sensor products and for applications across large wetlands and floodplains.

This study presents an ensemble stream flow simulation with probability of occurrence accounting for errors of the GR4J turned to the Senegal River upper the Manantali dam. Through this approach, probability is associated to simulation at each time, with step and reliability of issues depending on probability scores. Results including the reliability of the results permit decision-makers to judge the reliability of their simulations. Past errors pattern of the model is used to perturb the model for issuing ensemble scenarios rather than classical single deterministic. Basic and reverse Box-Cox transformation is carried out to allow treatment of the errors through weighted multivariate Gaussian distribution. Statistic errors are then used to perturb the hydrological model to obtain ensemble issues (RAW-Ens). Furthermore, a post-processing method (affine kernel dressing) is performed to produce a dressed ensemble (AKD-Ens). Ensembles are evaluated at deterministic and probabilistic scale. Diagrams (attribute and ROC) are also used for this purpose. Evaluating methods reveal through scores that the system is reliable and that dressing method (AKD) improves quality of the raw ensemble drawn from the perturbed model. Key words: Senegal River, Bafing, Manantali dam, Ensemble simulation, Kernel dressing.

Using Riyad Capital mutual funds as a proxy for Saudi Arabian mutual funds, this paper empirically compares the risk-adjusted performance and investment style of Islamic mutual funds with that of c...