Cheikh Anta Diop University

Mesoscale Convective Systems (MCSs) account for most of the rainfall over the Sahel and contribute substantially to extreme precipitation events (EPEs) that cause flooding in West Africa. However, the low density of ground-based observation networks limits the accurate monitoring and characterization of these events. Regional climate models, such as the Weather Research and Forecasting (WRF) model, help to compensate for this observational gap but still exhibit significant biases in simulating extreme precipitation.This study aims to reduce these biases by integrating the WRF model into a Supermodelling framework based on the dynamic combination of multiple model configurations, designed to exploit their complementary strengths.Two supermodels, SUPPERT-WRFA and SUPPERT-WRFB, are developed from three distinct WRF configurations that mainly differ in their convection schemes. SUPPERT-WRFA is trained using satellite-based IMERG precipitation, while SUPPERT-WRFB relies on atmospheric dynamical variables (U, V, and T) from ERA5. In both cases, the training strategy is based on a metric combining spatial correlation and root-mean-square error.The performance of the supermodels is evaluated for the simulation of EPEs in West Africa through a case study of an extreme precipitation event that occurred on 5 September 2020 in Senegal. The results show a significant improvement in the representation of extreme precipitation compared to individual WRF configurations, highlighting the strong potential of Supermodelling to improve extreme event prediction in regions with sparse observational coverage.

Groundwater in southeastern Senegal faces pressures from climate variability, overabstraction, and geogenic contamination. As part of a Geoscientists Without Borders initiative, we conducted an integrated geoscientific investigation in Saraya, Eastern Senegal, to map groundwater potential, assess water quality, and build local capacity. Transient electromagnetic (TEM) soundings and electrical resistivity tomography (ERT) profiles were acquired, supported by targeted geological mapping and groundwater sampling.Geophysical imaging identified fractures and deep regolith as the main water-bearing units, though highly variable in extent. The town of Badioula shows promising aquifer continuity with generally good water quality, while Saraya was characterized by poorer water quality.To complement the geophysical surveys, real-time monitoring was piloted using a LoRa-based network with water level and electrical conductivity sensors linked to a weather station. The system captured rainfall-driven recharge responses and conductivity fluctuations, providing a blueprint for cost-effective monitoring in remote regions.This integrated approach underscores the value of combining TEM, ERT, geochemistry, and low-cost monitoring to guide sustainable groundwater abstraction in crystalline basement terrains. Beyond technical outcomes, the project strengthened local expertise through MSc training, outreach, and workshops, highlighting hydrogeophysics as a tool for water security.

In Senegal, tuberculosis is endemic, and tuberculosis patients are supposed to be properly cared for in all healthcare facilities, but a significant proportion of them reach the top of the healthcare pyramid to receive adequate care, and there is little information available on the therapeutic pathway of tuberculosis patients prior to their admission at the reference facilities. Objective: To describe the therapeutic pathway of patients hospitalized in the national reference department with a diagnosis of tuberculosis and to identify the missed opportunities (for diagnosis and treatment). Methods: Retrospective study on the records of hospitalized tuberculosis patients from 2020 to 2022. The identification of factors associated with multifocal TB was carried out using a logistic regression model. The cumulative incidence of death was assessed using Kaplan-Meier curves, and the identification of prognostic factors was done using a Cox regression models. Results: We included 363 patients with a median (IQR) age of 39 (30-50) years, including 61.6% of men and 51.6% of people living with HIV. Before their admission at the national reference department, 88.6% had been seen at another healthcare facility. Missed opportunities for tuberculosis diagnosis were identified in 62.4% of them; otherwise, missed opportunities for tuberculosis treatment occurred in 28.7% of cases and missed opportunities for HIV infection screening in 43.4% of cases. Tuberculosis was unifocal in 30.4% of cases, bifocal in 35.8%, and multifocal in 33.8%. Multifocal tuberculosis was associated with the existence of a missed opportunity for tuberculosis treatment (OR = 3.2. The fatality rate was 7/100 person-months: 7.3/100 personmonths among people living with HIV compared to 6.8/100 person-months among others. After adjustment, age > 55 years (HR = 1.6; p – 0.038) and diabetes as a comorbidity (HR = 2; p – 0.024) were prognostic factors for tuberculosis; the risk of death was associated with a CD4+ T-cell count < 50/mm3 in people living with HIV, being 10 times higher in those with a CD4+ T-cell count < 50/mm3 . Conclusion: Tuberculosis was common, particularly among people living with HIV, whose therapeutic pathway with missed opportunities for diagnosis and treatment could contribute to their advanced immunosuppression upon arrival at the national reference department and, consequently, help explain the high lethality of tuberculosis.

Abstract The interannual variability of tropical Atlantic cyclones (TCs) has been linked to ENSO and the Atlantic Meridional Mode. Recent studies have also highlighted the role of the equatorial Atlantic in influencing Cape Verde TCs. However, the stationarity of these teleconnections has not yet been thoroughly examined. In this work, running correlations between the anomalous frequency of TCs originating in the Cape Verde region and tropical sea surface temperatures (SSTs), reveal a shift in recent decades. Although the overall frequency of Atlantic TCs has increased since the 2000’s, changes in atmospheric and oceanic background conditions have weakened the influence of SSTs on Cape Verde TCs. Furthermore, our assessment of eddy kinetic energy as an indicator of African easterly wave activity suggests that, in the context of global warming, the predictive power of sea surface temperatures may be diminished.

ABSTRACT Background Most births worldwide (>80%) occur in health care facilities, yet 2.3 million newborns die annually. If the know – do gap between evidence and implementation was closed, an estimated 752,000 newborn deaths could be prevented per year. To bridge this gap, we describe the co-design of the Implementation Toolkit for Small and Sick Newborn Care (Newborn Toolkit), a web platform and linked community of global implementers, facilitated by NEST360 and UNICEF. The Newborn Toolkit enables access to practical, curated resources, including tools for peer learning and adaptation to country contexts. Methods A systematic three step process was followed. Step 1) Structure: We used an organising framework of WHO and UNICEF ten core components for health systems strengthening. We then reviewed relevant knowledge management platforms to identify elements facilitating user engagement. Step 2) Content: >300 implementers collated publications and tools for ten core components. Step 3) Refining and building community: User data analytics and surveys plus direct feedback from the global communities of practice provided data to improve website and webinar content. Results Step 1) Structure: In 2020, the Newborn Toolkit website structure was co-designed based on the ten core components. Step 2) Content: Working groups, organised by core components, collated over 1,100 resources in 15 languages. Step 3) Refining and building community: Cross-country learning was facilitated through 45 webinars with multi-disciplinary speakers from all continents including caregivers, clinicians, non-governmental organisation representatives, engineers, and data scientists. French language translation and engagement was added between 2023-2025. Unique user counts increased with 28,146 in 2023 to 62,561 in 2025 from 198 countries and territories. The most viewed content includes WHO guidelines, neonatal floor plans, the ABC device costing tool, and data tools. Conclusions Given the urgency for accelerated progress for newborn survival by 2030, rapid implementation of proven solutions is needed. It is crucial that implementers can access evidence and tools to adapt for their specific context, rather than “reinventing the wheel”. Systems change is complex, requiring novel approaches to make it doable, such as standard, simplified action pathways available on the Newborn Toolkit. Gaps to address include evidence availability in multiple languages. KEY FINDINGS WHAT WAS KNOWN? 2.3 million neonatal deaths are estimated annually and 65 countries are at-risk of missing Sustainable Development Goal 3.2 of reducing the number of neonatal deaths to less than 12 per 1,000 live births by 2030 There exists a know–do gap in global newborn health referring to the inability to translate evidence, what is known to work, into practice to improve health outcomes for WHO-UNICEF level-2 Small and Sick Newborn Care Frameworks based on country experiences have been created to guide health systems strengthening such as the WHO/UNICEF core components; however, operationalisation is needed Evidence, guidelines, and resources for Small and Sick Newborn Care were available; however, there existed a gap in knowledge management platforms dedicated to enabling evidence-based implementation of health systems strengthening interventions in low-resource settings WHAT WAS DONE THAT IS NEW? We co-designed a knowledge management platform for resources including tools, readings, and case studies to bridge the know–do gap for Small and Sick Newborn Care in low-resource settings Content and resources on the site were organised according to the ten WHO/UNICEF core components for health systems strengthening plus infection prevention and control This platform was operationalised and scaled by linking to, and engaging with, a global community of practice We applied a continuous learning and feedback integration approach to develop and refine content, enable accessibility including by language, and tailor engagement initiatives to implementer needs informed by website user and webinar data analytics WHAT WAS FOUND? The platform hosts over 1,100 tools and readings with resources available in 15 languages Between 2021–2025, this platform had 157,452 unique users, from 198 countries and territories 45 webinars were hosted between 2022–2025 showcasing implementation case studies and facilitating cross-country learning Knowledge management and targeted engagement can enable uptake of information by organising content in practical, digestible, and feasible formats WHAT NEXT? The know–do gap in Small and Sick Newborn Care needs to be closed. Providing up-to-date, relevant evidence that adapts to emerging knowledge and local learning, alongside leadership and financial inputs, could facilitate quality care delivery through data-driven decision making Bridging language barriers, through content translation, is a priority and crucial to enable wider access to up-to-date evidence

This study analyzes the intras seasonal variability of agroclimatic parameters in the Groundnut Basin between 1950 and 2022 based on daily rainfall data from ten stations and five posts. The start and end dates of the rainy season were thus determined, and the length of the rainy season, seasonal rainfall accumulation, number of rainy days, and dry spells were calculated in order to assess their spatiotemporal variability and trends in relation to rainfall breaks.The results confirm that the rainy season starts in the southeast of the basin and ends in the north. Seasonal rainfall, the length of the rainy season, and the number of rainy days, are higher in the south and center, while the maximum dry spells are longer in the north (14 days). On average, the rainy season generally begins in June in the south and center and in July in the north, ending in November in the south, October in the center, and September in the north. However, since the Sahelian climate crisis of the 1970s, the rainy season has become unpredictable, with delayed starts, early ends, and shorter wintering periods.Despite a slight increase in rainfall since 2000, the improvement in agroclimatic conditions remains moderate and spatially contrasting.

This study aims to evaluate the phytochemical composition of <i>Melothria maderaspatana</i> (L.) Cogn. fruits, a plant recognized in African and Indian pharmacopeias, and to physicochemical characterize its fixed oil extract, in order to enhance its potential in phytomedicine. Fruits harvested in Taïba Ndiaye (Senegal) in December 2021 underwent qualitative phytochemical screening on hexane, ethyl acetate, methanolic, and aqueous extracts, followed by Soxhlet oil extraction (yield: 7.98%). Detected secondary metabolites include polyphenols (except hexane extract), flavonoids (aqueous extract), alkaloids (hexane and aqueous extracts), sterols/polyterpenes (except aqueous extract), leucoanthocyanins (except hexane extract), coumarins (hexane/ethyl acetate extracts), and gallic tannins (aqueous extract); saponins, mucilages, and catecholic tannins were absent. Oil characterization according to AFNOR standards reveals: iodine value (II) = 4.8 ± 0.07 g I₂/100 g, acid value (IA) = 1.0 ± 0.1 mg KOH/g, saponification value (IS) = 145.8 ± 0.05 mg KOH/g, peroxide value (IP) = 8.0 ± 0.3 µg O₂/g, and ester value (IE) = 144.8 ± 0.05 mg KOH/g. These results indicate a non-drying oil with low unsaturation, oxidation stability, and low free fatty acid content, highlighting the potential of <i>M. maderaspatana</i> as a source of lipids and bioactive compounds for nutraceutical and therapeutic applications, warranting complementary fatty acid analysis and toxicological evaluation.

This paper empirically tests the Environmental Kuznets Curve (EKC) hypothesis for sub-Saharan Africa, using CO₂ emission as a proxy for environmental quality. The analysis employs panel pooled data for 39 countries from 1990 to 2019. We find evidence of an inverted U-shaped relationship between income and emissions, as GDP per capita has a positive effect and its square has a negative effect on CO₂ emissions, thereby supporting the EKC hypothesis. Our results reveal a dual role for renewable energy. When CO₂ emissions are the dependent variable, renewable energy consumption significantly reduces emissions, while non-renewable energy increases them. Additionally, population size and literacy rate are found to positively affect CO₂ emissions. In contrast, when economic growth is the dependent variable, renewable energy has a positive and significant influence. These findings indicate that expanding renewable energy production in sub-Saharan Africa offers a dual advantage, enhancing environmental quality while also contributing to stronger economic performance. By demonstrating that renewable energy reduces CO₂ emissions and supports growth, the results provide important guidance for policymakers seeking to advance sustainable development pathways that are compatible with long‑term environmental conservation across the region.