École Polytechnique de Thiès

Onsite sanitation coverage has expanded significantly since 2020, driven by global commitments to eliminate open defecation and the need for adaptable solutions in rapidly urbanising small- and medium-sized cities (<1 million inhabitants) in Low- and Middle-Income Countries. Currently, 53% of individuals with access to a toilet depend on onsite sanitation systems. Despite this prevalence, the contribution of greenhouse gas emissions from household-level excreta storage to climate change remains poorly quantified due to limited empirical evidence. We addressed this gap by conducting direct measurements of methane emissions from 146 onsite sanitation containment units locally referred as pit latrines, holding tanks and septic tanks, across Senegal, Ethiopia, Uganda and Nepal. Methane emission rates exhibited strong skewness with a geometric mean of 7.9 g CH₄ capita⁻¹ day⁻¹, indicating that onsite sanitation containment units alone may account for approximately 3.8% of global anthropogenic CH₄ emissions.

The exponential growth of mobile gaming in Africa raises the question of whether existing network infrastructures can sustain competitive e-sports experiences. This paper presents a crowdsourced measurement approach to assess mobile network quality in Senegal, where mobile gaming has become the dominant form of entertainment. Combining more than 30,000 geolocated network measurements with a nationwide sociological survey of 801 gamers, this research analyzes how real-world Quality of Service (QoS) parameters—such as throughput, latency, and signal strength affect the Quality of Experience (QoE) of mobile players. Results show that while 4G and fiber connectivity have expanded significantly, disparities in coverage and latency still constrain online competitiveness. The study demonstrates that mobile e-sports can serve as both a digital inclusion indicator and a demanding benchmark for telecommunication performance in developing countries.

Abstract We establish flow invariance results for semilinear systems governed by non-Hille–Yosida operators under time-dependent closed convex constraints. A new subtangential condition is introduced, together with explicit sufficient conditions for positive invariance formulated in terms of the resolvent and the nonlinear term. The results apply to systems with non-densely defined operators and time-varying constraints, and are illustrated by applications to an age-structured predator–prey model, a biofilm model, and a class of neutral functional differential equations.

The agricultural environment is facing climate change and severe erosion of arable land. Water management in daily operations is crucial, especially in Senegal. In addition, without disregarding the type of soil and amendment, the water quality and the water quantity define the types of agriculture we can do. In this work, we measured with our network sensors the water quality and the soil parameters in order to identify the irrigation frequency that can cause soil erosion and can avoid an optimal development of crops. Further, we give a set of results for decision-making in an irrigation scheme and soil works. After analysing the one month data from our sensors network, we proposed 2 types of amendments that contribute to soil health and limit the appearance of sedimentation, to play a role in delaying capillary upwelling, which can cause stress on crops. In addition, we highlight a set of relationships between the main parameters that define crop cultivation abilities like pH (hydrogen potential), EC (electrical conductivity), N (nitrogen), P (phosphorus), K (potassium), and Fertility.

Electric tricycles are one of the most promising options for reducing CO2 emissions in sub-Saharan Africa, with lower energy requirements. They are also suitable for transporting passengers and goods in rural areas of sub-Saharan Africa, where urbanization is rife. The lack of recharging infrastructure is holding back the development of tricycles. This paper proposes a methodology for the design of a photovoltaic (PV)-battery stand-alone fast charging station for electric tricycles in Thienaba, Senegal. An ultra-fast charging station powered by photovoltaic panels was designed, modelled and simulated using the Matlab/Simulink platform. The results of this work gave a photovoltaic array with a peak power equal to 45 kW. At least, eight tricycles can be charged between 11 am and 2 pm. At the same time, the storage system can be charged up to 70% of its total charge.

Flow records for stations in the Casamance basin are incomplete. Several gaps were noted over the 1980-2021 study period, making this study tedious. The aim of this study is to assess the potential impact of climate change on the flow of the Casamance watershed at Kolda. To this end, hydrological series are simulated and then extended using the GR2M rainfall-runoff model, with a monthly time step. Projected climate data are derived from a multi-model ensemble under scenarios SSP2-4.5 (scenario with additional radiative forcing of 4.5 W/m 2 by 2099) and SSP5-8.5 (scenario with additional radiative forcing of 8.5 W/m 2 by 2099). An analysis of the homogeneity of the rainfall data series from the Kolda station was carried out using KhronoStat software. The Casamance watershed was then delimited using ArcGIS to determine the morphometric parameters of the basin, which will be decisive for the rest of the work. Next, monthly evapotranspiration was calculated using the formula proposed by Oudin et al. This, together with rainfall and runoff, forms the input data for the model. The GR2M model was then calibrated and cross-validated using various simulations to assess its performance and robustness in the Casamance watershed. The version of the model with the calibrated parameters will make it possible to extend Casamance river flows to 2099. This simulation of future flows with GR2M shows a decrease in the flow of the Casamance at Kolda with the two scenarios SSP2-4.5 and SSP5-8.5 during the rainy period, and almost zero flows during the dry season from the period 2040-2059.

Ehrlichia chaffeensis is a tick-borne disease transmitted by ticks to dogs. Few studies have mathematical modelled such tick-borne disease in dogs, and none have developed models that incorporate different ticks' developmental stages (discrete variable) as well as the duration of infection (continuous variable). In this study, we develop and analyze a model that considers these two structural variables using integrated semigroups theory. We address the well-posedness of the model and investigate the existence of steady states. The model exhibits a disease-free equilibrium and an endemic equilibrium. We calculate the reproduction number (T0). We establish a necessary and sufficient condition for the bifurcation of an endemic equilibrium. Specifically, we demonstrate that a bifurcation, either backward or forward, can occur at T0=1, leading to the existence, or not, of an endemic equilibrium even when T0<1. Finally, numerical simulations are employed to illustrate these theoretical findings.

Malaria is one of the most common mosquito-borne diseases widespread in tropical and subtropical regions, causing thousands of deaths every year in the world. In a previous paper, we formulated an age-structured model containing three structural variables: (i) the chronological age of human and mosquito populations, (ii) the time since they are infected, and (iii) humans waning immunity (i.e. the progressive loss of protective antibodies after recovery). In the present paper, we expand the analysis of this age-structured model and focus on the derivation of entomological and epidemiological results commonly used in the literature, following the works of Smith and McKenzie. We generalize their results to the age-structured case. In order to quantify the impact of neglecting structuring variables such as chronological age, we assigned values from the literature to our model parameters. While some parameters values are readily accessible from the literature, at least those about the human population, the parameters concerning mosquitoes are less commonly documented and the values of a number of them (e.g. mosquito survival in the presence or in absence of infection) can be discussed extensively.

Increasing numbers of US older adults die in long-term care facilities. This qualitative study explored nursing home resident, family member, and staff perspectives and preferences regarding end-of-life care for the resident. From 67 potential participants referred by staff, 47 were found eligible and consented, including 16 residents, 10 family members, and 20 staff. A semistructured questionnaire guided the interview process and included questions such as what matters most at the end of life and whether participants would opt for any of the 8 aggressive treatments proposed for a resident at the end of life. Data were analyzed using descriptive and pattern coding for thematic interpretation. The 3 themes that emerged were centrality of comfort, what matters most at the end of life, and promoting comfort. All participant groups overwhelmingly endorsed comfort as a priority. Some participants would accept aggressive treatment to alleviate suffering and promote comfort. Residents were concerned about the well-being of their families, whereas family members emphasized the importance of their presence and that their dying relatives were not suffering. Staff sometimes filled this role on their behalf. Ancillary staff emphasized bathing, dressing, and grooming the resident to preserve the resident's dignity. The results support comfort as a priority for care at the end of life and the need for more discussion to increase mutual agreement on goals of care and what promotes comfort for the resident and family.