University of Bamako

The connection between a photovoltaic array and a load is still an interest subject of research. The impedance matching between a PV array and a load is a technological problem that basically means the maximum power transfer from a PV panel to a load. Although there are many works devoted to the problem of the maximum power point tracking (MPPT) in a PV array, only few of them deal with the nature of the power interface while most of them focus on different types of tracking algorithms. The problem is addressed in this study by a systemic approach from a power interface point of view in order to obtain high levels of efficiency, reliability and flexibility. Moreover, the simulations and experimental results prove that the proposed system gives a fast response and is suitable for rapidly changing weather conditions. In steady state, the tracking of the maximum power point with the proposed system is very effective or efficient and the quality of the signals is substantially improved. In addition, the output power fluctuation is also reduced, which is a major problem in all MPPT maximum power point trackers and especially the traditional ones, and reducing the output power fluctuation is a goal. adapting it to the load.

Although radiotherapy is an essential part of comprehensive cancer care, access is heavily limited in most sub-Saharan African (SSA) countries. Patients' barriers to care can be grouped as availability, accessibility, accommodation, affordability, and acceptability. We aimed to assess cancer patient- and caregiver-reported barriers in nine SSAn countries (Republic of the Congo, Ethiopia, Gabon, Kenya, Mali, Nigeria, Tanzania, Uganda, and Zimbabwe). We conducted a telephone-based survey among 553 randomly selected patients with breast, cervical, colorectal, and prostate cancer, Kaposi sarcoma and non-Hodgkin lymphoma diagnosed between 2018 and 2019 registered in population-based registries of the African Cancer Registry Network. We inquired about receipt of radiotherapy and barriers irrespective of recalling a recommendation. Among all categories, 21.6% (Use of alternative medicine) to 39.6% (Cost of treatment) of patients reported severe barriers. Most common was problematic Cost of treatment (69.0% overall). A high share of patients from Congo, Kenya, Nigeria, and Tanzania reported barriers. Higher education and wealth were associated with reduced problems in all categories except increased problems with Fear and Use of alternative medicine. Receipt of radiotherapy was associated with fewer problems with Availability of transport (odds ratio [OR]: 0.34; 95% confidence interval [CI], 0.13-0.88) and Trust in healthcare workers (OR: 0.44; 95% CI, 0.24-0.8), and increased Fear (OR: 2.33; 95% CI, 1.33-4.05). Seeing that one-third of the patients reported severe problems in all dimensions, shortage of radiotherapy units is not the only problematic aspect of access to radiotherapy. Improvements in affordability, patient-healthcare worker communication, and psychosocial support are needed.

ABSTRACT Background Severe Plasmodium falciparum malaria is a leading cause of death in sub-Saharan Africa, with most deaths occurring in children younger than five years of age. The RTS,S/AS01 E (RTS,S) malaria vaccine delivered seasonally with Seasonal Malaria Chemoprevention (SMC) led to a two-third reduction in severe malaria and malaria deaths compared with either intervention given alone. The aim of this study was to assess the seasonal distribution and clinical presentation of children admitted in hospital with severe malaria who received RTS,S with or without SMC, and whether seasonal vaccination with RTS,S affected their distribution and clinical presentation. Methods We conducted a secondary ad-hoc analysis of hospital admissions in children aged 5 to 17 months of age when enrolled in the RTS,S + SMC trial in April 2017 in Houndé, Burkina Faso, and Bougouni, Mali, and who were followed until they reached five years of age. Results Three hundred and thirtythirty-seven serious adverse events were reported during the trial with 222 (65.9%) in Burkina Faso and 115 (34.1%) in Mali, and 48.1% (162/337) were due to severe malaria. The mean age of children with severe malaria was 2.9 years; 79.0% (128/162) of the cases occurred in children aged 3 years or less and 21.0% (34/162) in those aged 4 to 5 years. The most common presentation was severe anemia reported in 50% (81/162) of children, followed by repeated convulsions 25.3%, (41/162), prostration 11.1%, (18/162), hyperparasitaemia 8.0%, (13/162) and cerebral malaria 6.2%, (10/162). Severe malaria anemia was a more frequent form of severe malaria in children in the SMC alone arm 62.1%, (36/58) and lower in children in the SMC+ RTS,S arm 37.1%, (13/35), p=0.048. There was no significant difference in frequency of other clinical presentations between the study arms. Most severe malaria cases, 85.8% (139/162) occurred during the transmission season (July to December). Conclusions Severe anaemia was the most common presentation of severe malaria and was most frequent in the SMC alone arm. Children aged 3 years or less were the most affected and almost all the cases occurred between July and December. Trial registration ClinicalTrials.gov , NCT04319380

Depuis plus de cinquante ans, les inondations sont récurrentes dans le sud du Mali, en particulier dans le bassin versant du Bendougou, où se trouve la ville de Bla. Ces inondations, considérées comme dangereuses, suscitent une attention croissante de la part du public et de la communauté scientifique. Cette étude utilise la géo-informatique pour évaluer les zones à risque d'inondation à l'aide d'une approche multicritères basée sur les systèmes d'information géographique (SIG). Les données utilisées comprennent un modèle numérique d'élévation (MNE) provenant d'ALOS PALSAR (2014, résolution de 12,5 m), 30 ans de données cumulées sur les précipitations, des données démographiques provenant de WORLDPOP et des images satellite Landsat 8 OLI de 2023 (résolution de 30 m). Le MNT a été utilisé pour caractériser le terrain en termes de pente, d'altitude et de densité de drainage. Les images Landsat ont été analysées pour cartographier l'utilisation et la couverture des sols. Le processus analytique hiérarchique (PAH) a été utilisé pour attribuer des pondérations à chaque facteur en fonction de son importance relative. La carte finale des risques d'inondation a été générée à partir d'une combinaison linéaire pondérée de la carte des aléas, de la densité de population et des données sur l'utilisation des sols. Les résultats indiquent que 40 % de la superficie du bassin versant (soit 260505 hectares) est classée comme présentant un risque faible, 33 % un risque modéré, 23 % un risque très faible et seulement 4 % un risque élevé à très élevé. Les zones les plus vulnérables sont principalement situées dans les environs urbains de Bla. Ces résultats soulignent la nécessité urgente de renforcer les efforts de prévention et de gestion des inondations dans cette localité en rapide urbanisation. For over fifty years, flooding in southern Mali has been recurrent, particularly within the Bendougou watershed, where the city of Bla is located. These floods, regarded as dangerous, have attracted growing attention from the public as well as the scientific community. This study employs geoinformatics to evaluate flood risk zones using a multi-criteria approach based on Geographic Information Systems (GIS). The data used include a Digital Elevation Model (DEM) from ALOS PALSAR (2014, 12.5 m resolution), 30 years of cumulative rainfall data, demographic data from WORLDPOP, and Landsat 8 OLI satellite imagery from 2023 (30 m resolution). The DEM was used to characterize the terrain in terms of slope, elevation, and drainage density. Landsat imagery was analyzed to map land use and land cover. Flood hazard was estimated by integrating topographic, rainfall, and land use data. The Analytic Hierarchy Process (AHP) was applied to assign weights to each factor according to its relative importance. The final flood risk map was generated through a weighted linear combination of the hazard map, population density, and land use data. The results indicate that 40% of the watershed area (equivalent to 260,505 hectares) is classified as low risk, 33% as moderate risk, 23% as very low risk, and only 4% as high to very high risk. The most vulnerable areas are predominantly located in the urban vicinity of Bla. These findings highlight the urgent need to strengthen flood prevention and management efforts in this rapidly urbanizing locality.

As the geopolitical context becomes increasingly complex, journalists and researchers face major challenges in conducting investigations in conflict zones. The Sahel, particularly the countries of the Alliance of Sahel States (Burkina Faso, Mali and Niger), an African region particularly affected by instability and violence, is a perfect example. In order to overcome these difficulties, new remote investigation methods have been developed, enabling us to continue documenting and analyzing crisis situations despite restricted access to the field. This paper will focus on these new investigative techniques with a view to understanding and substantiating the facts.

Introduction: ENT pathologies are all diseases in the ENT sphere, in developing countries, such as Chad, due to poverty and promiscuity; ENT diseases therefore remain a real public health problem. The aim of this work was to identify the epidemio-clinical aspects of ENT diseases in children and to analyse primary prevention measures. Method and material: this is a prospective descriptive study carried out in the ENT-HNS department of the mother and children hospital of N'Djamena (Tchad) from January 1, 2024 to June 30, 2024. All patients received in ENT consultations aged 0 to 15 years were included. Results: We were able to collect 328 cases dominated by boys, 181 cases (55.2%) against 147 girls (44.8%) with a sex ratio of 1.23 in favor of boys. Children under 5 years of age were the most represented, 195 cases or 59.5%; 215 cases or 65.5% were up to date with vaccination against 113 cases or 34.5% not up to date with vaccination. The oral-pharyngo-laryngeal region was affected in 44.2% followed by the nasosinusal, cervical and atrial regions which respectively accounted for 20.2%; 18,7%; and 17.1%. Odynophagia was the most common reason for consultation, with 96 cases (29.3%); The most common condition was tonsillitis, which accounted for 95 cases (29.0%). Infections and/or inflammations accounted for 280 cases, or 85.4%. Conclusion: ENT pathologies in children are frequent in consultations, they are dominated by infections and or inflammation. Simple preventive measures could help reduce their incidence, in particular rigorous monitoring of the vaccination schedule and raising awareness among parents and other public actors of the population on the rules of children's lifestyle.

Introduction : La vaccination permet d’immuniser les enfants contre les maladies meurtrières et invalidantes. Selon l’organisation mondiale de la santé, la plupart des enfants incomplètement vaccinés se trouvent en Afrique. Au Mali, 55% des enfants de 12-23 mois étaient complètement vaccinés et 14% n’avaient reçu aucun vaccin en 2018. Notre étude avait pour objectif de déterminer les facteurs associés à la vaccination incomplète des enfants de 15-23 mois de Tominian dans un contexte d’insécurité en 2020. Méthodes : Nous avons mené une étude transversale analytique sur 508 mères d’enfants âgés de 15-23 mois. Un échantillonnage stratifié à trois degrés a permis d’identifier les aires de santé, villages et mères d’enfants. Nous avons testé l’association entre la vaccination et ses déterminants probables en utilisant une régression logistique multiple à un niveau de signification de 0,05 et un intervalle de confiance à 95% (IC95%) à l’aide d’Epi-info 7.2.2 et de Medcalc. Le test de Hosmer et Lemeshow a été utilisé pour juger l’adéquation du modèle de régression multiple obtenu après l’analyse multivariée. Résultats : L’âge moyen des mères et des enfants était respectivement de 27±6 ans et de 19±3 mois. La couverture vaccinale de la 2ème dose de vaccin antirougeoleux était de 34,8%. La méconnaissance de l’importance de la vaccination (ORa[IC95%]=9,3[2,2-40,6], p=0,003), la connaissance de moins cinq maladies cibles de la vaccination (ORa[IC95%]=3,8[1,4-10,2 ], p˂0,008), l’absence de revenue (ORa=[IC95%]=2,9[1,7-5,2], p˂0,001), le temps d’attente long (ORa=[IC95%]=2,4[1,5-3,7], p˂0,001), l’accouchement à domicile (ORa[IC95%]=2,3[1,5-3,5], p˂0,001) et la non tenue de causeries éducatives par les vaccinateurs (ORa=[IC95%]=1,8[1,2-2,8], p=0,009) étaient statistiquement associés à la vaccination incomplète des enfants. Conclusion : La couverture vaccinale n’était pas associée à l’insécurité. Nous recommandons la mise en œuvre des activités de rattrapage vaccinale, de sensibiliser et de soutenir la création d’activités génératrices de revenue pour les mères afin de contribuer à l’amélioration du statut vaccinal des enfants.

The species group, including the West African Mimopacha rotundata Hering, 1941 (the type locality is in Senegal), and two Central African M. brunnea Hering, 1941 (the type locality is in Equatorial Guinea) and M. audeoudi Romieux, 1935 (the type locality is in the southern Democratic Republic of the Congo), was reviewed: 1) type specimens of all species were examined, dissected, and illustrated; 2) new collection localities were provided to all species based on additional non-type material; 3) the subspecies M. brunnea fusca Hering, 1941 synonymous to M. brunnea was moved in synonymy with M. audeoudi (syn. n.); 4) two new species were described from Sudan and South Sudan (M. brysoni sp. n.), and Ethiopia (M. bradyi sp. n.). Four species, apart from M. brunnea, were barcoded and used in phylogenetic reconstruction, all had interspecific p-distances above 4%.