Abdou Moumouni University

About: Abdou Moumouni University is a education organization based out in Niamey, Niamey, Niger. It is known for research contribution in the topics: Population & Agriculture. The organization has 796 authors who have published 808 publications receiving 17478 citations. The organization is also known as: University of Niamey & Abdou Moumouni Dioffo University.

Land use mapping using Sentinel-1 and Sentinel-2 time series in a heterogeneous landscape in Niger, Sahel

Abstract: Land use maps describe the spatial distribution of natural resources, cultural landscapes, and human settlements, serving as an important planning tool for decision makers. In the Sahel area, such information is valuable for risk management and mitigation in challenging sectors like food security, flood control, and urban planning. Due to its uniform quality across large areas in regular time steps, remote sensing imageries are essential input for producing land use maps. However, spatially and temporally heterogeneous landscapes in Sahel make classification of landscape features difficult. Our overall goal is to create an accurate, high resolution land use map covering Niamey, the capital of Niger and its surroundings which represents the unique landscape features in the Sahel using Sentinel-1 and Sentinel-2 archives. We assessed the performance of three commonly used classifiers (i.e. Maximum Likelihood (ML), Support Vector Machine (SVM) and Random Forest (RF)) for land use classification. To understand the utility of different features from Sentinel-1 and Sentinel-2 imagery for classification, we performed feature selection and compared mapping accuracies with and without feature selection. To leverage the strength of each classifier, we developed a classifier ensemble (CE) map based on the mapping accuracy of each land use class and each classifier. The results of this study showed that the performance of individual classifiers depends on feature selection method and accuracies can be improved by combining different classifiers. The ensemble map had an overall accuracy of 72 ± 3.9% and it was found superior in terms of accuracy particularly with respect to built-up areas compared to the existing global land cover products in the study area. Our classification scheme also better characterized the regional environment in the Sahel. For example, we mapped rice and bare rocks that have important regional implication, which are not included in the existing products. Overall, our approach highlights the potentiality of combining multi-modal imageries and multiple classifiers for mapping a heterogenous environment such as the Sahel with high spatial resolution.

Late-time cosmological approach in mimetic f(R, T) gravity

Abstract: In this paper, we investigate the late-time cosmic acceleration in mimetic f(R, T) gravity with the Lagrange multiplier and potential in a Universe containing, besides radiation and dark energy, a self-interacting (collisional) matter. We obtain through the modified Friedmann equations the main equation that can describe the cosmological evolution. Then, with several models from $$\mathcal {Q}(z)$$ and the well-known particular model f(R, T), we perform an analysis of the late-time evolution. We examine the behavior of the Hubble parameter, the dark energy equation of state and the total effective equation of state and in each case we compare the resulting picture with the non-collisional matter (assumed as dust) and also with the collisional matter in mimetic f(R, T) gravity. The results obtained are in good agreement with the observational data and show that in the presence of the collisional matter the dark energy oscillations in mimetic f(R, T) gravity can be damped.

Melanin in a dentigerous cyst and associated adenomatoid odontogenic tumor

Abstract: The authors report on a case of dentigerous cyst associated with odontogenic adenomatoid tumor in an 8-year-old black Nigerian boy. Both the cyst and the tumor contained melanocytes and melanin-laden epithelial cells. To their knowledge this is the first reported case of melanotic follicular cyst and adenomatoid tumor. A review of the literature revealed that melanin is rarely found in odontogenic lesions. Since the neural crest influence on the development of odontogenic tissues is well established, the occurrence of melanocytes in these tissues is not surprising. A racial predisposition may be present; black patients predominated in the 15 reported cases of melanotic odontogenic lesions.

Intersectoral collaboration between the medical and veterinary professions in low-resource societies: The role of research and training institutions.

Abstract: While veterinarians have been the main driver of the One Health initiative, the medical profession does not seem to be fully aware of how veterinary science can contribute to human public health. It was postulated that transdisciplinarity could help fill knowledge gaps and that encouraging such transdisciplinarity should start with undergraduate students. Furthermore, intersectoral collaboration on zoonoses should not ignore the social sciences (e.g. assessment of indigenous knowledge and perception; participatory surveillance), which can contribute to a better understanding of the transmission of diseases and improve communities' participation in disease control activities.