Aménagements hydro-agricoles et santé (vallée du fleuve Sénégal)

Les schistosomiases sont actuellement absentes du périmètre irrigué MO 6bis (moyenne vallée du fleuve Sénégal). Les hôtes intermédiaires (#Biomphalaria et #Bulinus) n'ont pas été, pour l'instant tout au moins, rencontrés dans la zone aménagée. Les analyses coprologiques effectuées sur bovins à proximité du périmètre, ont montré que 40% d'entre eux étaient atteints de strongyloses alors que les trématodoses sont absentes. (Résumé d'auteur

Mapping Landscapes: Integrating GIS and Social Science Methods to Model Human-Nature Relationships in Southern Cameroon

Participatory mapping and GIS are both necessary to model the interactions between humans and their environment. A case study from the forest margin in the Congo Basin demonstrates how data from participatory community mapping and other social science methods can be prepared for quantitative modelling. This approach bridged the gap between spatial modelling data and social decision-making in space by elaborating a geographically consistent social representation of the landscape and giving a geographical base to the connection between land use, its cultural representation, and its social management. This was achieved through an iterative process of GIS cartography, using feedback from village informants and field checking, to transpose the spatial references from participatory mapping sketches into reliable geographic locations. As well as demonstrating the utility of such data for modelling, this work clarified the distribution of land rights among the six main owner-clans spread through the eight hamlets in the watershed. The 'basin' of spatial resources and its relation to the rules of land use and natural resource management were defined for each clan. Land-use systems at the forest-agriculture interface in the study area proved to be complex, strongly driven by social rules and influenced by history and settlement strategies. These social and historical aspects established the framework within which communities make current decisions and interventions

Efficient Learning of Accurate Surrogates for Simulations of Complex Systems

Machine learning methods are increasingly used to build computationally inexpensive surrogates for complex physical models. The predictive capability of these surrogates suffers when data are noisy, sparse, or time-dependent. As we are interested in finding a surrogate that provides valid predictions of any potential future model evaluations, we introduce an online learning method empowered by optimizer-driven sampling. The method has two advantages over current approaches. First, it ensures that all turning points on the model response surface are included in the training data. Second, after any new model evaluations, surrogates are tested and "retrained" (updated) if the "score" drops below a validity threshold. Tests on benchmark functions reveal that optimizer-directed sampling generally outperforms traditional sampling methods in terms of accuracy around local extrema, even when the scoring metric favors overall accuracy. We apply our method to simulations of nuclear matter to demonstrate that highly accurate surrogates for the nuclear equation of state can be reliably auto-generated from expensive calculations using a few model evaluations.Comment: 13 pages, 6 figures, submitted to Nature Machine Intelligenc

Caracterisation agromorphologique, chimique et biochimique des noix brutes de trois provenances d’anacardiers (Anacardium occidentale L.) au Sud du Senegal

La sécurité alimentaire est l’une des préoccupations majeures des hommes dans le monde. Pour l’atteindre, les populations rurales tirent une grande partie de leurs alimentations dans les Produits Forestiers Non Ligneux. Anacardium occidentale L., une espèce agroforestière très prisée n’est pas en reste. Cependant, des études sur la valeur alimentaire et nutritionnelle de ses noix sont limitées et restent parcellaires. L’objectif de cette recherche est d’évaluer les teneurs en éléments nutritifs des noix brutes de Anacardium occidentale L. collectées à Ziguinchor, Sédhiou et Kolda. Pour ce faire, dans chaque zone, trois kilogrammes de noix ont été prélevées de manière aléatoire dans différents lieux de stockage. Puis les mensurations ont porté sur 450 noix par provenance. Les noix ont été ensuite décortiquées puis soumises à une analyse minérale (chimique et biochimique). Une analyse uni et multivariée a été effectuée à l’aide de XLSTAT 6.0. L’analyse a montré l’existence d’une variabilité des caractéristiques entre les provenances. Une corrélation forte, significative mais négative a été détectée entre le poids des amandes et la cellulose brute, ce qui signifierait que les amandes de petite taille sont plus sucrées. A travers cette étude, plusieurs possibilités s’offrent aux différents acteurs de la chaine de valeur anacarde. English title: Agromorphological, chemical and biochemical characterization of <I>Anacardium occidentale L.</I> in Sud Senegal Food security is one of the major concerns of people around the world. To achieve this, rural populations derive a large part of their food from Non-Wood Forest Products. Anacardium occidentale L., a highly prized agroforestry species, is not to be outdone. However, studies on the food and nutritional value of its nuts are limited and remain fragmented. The objective of this research is to evaluate the nutrient content of raw nuts of Anacardium occidentale L. collected in Ziguinchor, Sédhiou and Kolda. To do this, in each area, three kilograms of nuts were taken at random from  different storage locations. Then the measurements were carried out on 450 nuts per provenance. The nuts were then shelled and then subjected to mineral analysis (chemical and biochemical). Univariate and multivariate analysis was performed using XLSTAT 6.0. The analysis showed the  existence of variability in characteristics between provenances. A strong, significant but negative correlation was detected between the weight of the almonds and the crude fiber, which would mean that the small almonds are sweeter. Through this study, several possibilities are available to the various players in the cashew value chain

Evaluation of Neonatal Transport in Western Switzerland: A Model of Perinatal Regionalization.

Neonatal transport is an essential part of regionalization for highly specialized neonatal intensive care. This retrospective analysis of prospectively collected data on neonatal transport activity in a large Swiss perinatal network more than 1 year, aimed to quantify this activity, to identify the needs for staff, and the demands regarding know-how and equipment. Of the 565 admissions to the tertiary neonatology clinic, 176 (31.2%) were outborn patients, transported as emergencies to the level III unit. In 71.6% of cases, respiratory insufficiency was one of the reasons for transfer. Circadian and weekly distribution showed increased transport activity on workdays between 8 am and 10 pm, but regular demands for emergency transports regardless of the time frame require a neonatal transport team available 24/7. This study highlights the importance of neonatal transport and unveils several functional and infrastructural insufficiencies, which led to suggestions for improvement

Prevalence et facteurs associes a l’halitose buccale : Etude dans une population generale senegalaise

Introduction: Halitosis is a common complain among dental patients, chronic among 50% of the adult population, and of oral origin in 90% of the cases. The objective of this study was to evaluate the prevalence and related factors of oral halitosis among a senegalese population. Material and method: This was a transversal descriptive study of 396 Senegalese adults using a 24-point self-assessment questionnaire on halitosis. All subjects were examined to estimate the organoleptic means and to measure the Sulfur Volatile Compounds (SVC), using a halimeter. Halitosis was diagnosed when the level of sulfur volatile Compound was ≥125 ppb and the organoleptic score ≥ 2. Data were statistically analyzed using the chi2 test. Results: The global prevalence of halitosis was 32.3 %. The difference was not statistically significant between male and female. Among the 396 patients suffering from bad breath, 128 had a permanent halitosis and 52 had a physiological halitosis. The means of the organoleptic scores were 3.12 and that of the (SVC) were 273.9 ppb. Conclusion: The results of the study showed a relation between the organoleptic tests and the level of sulfur volatile compounds (SVC). Keywords: Halitosis, organoleptic tests, sulfur volatile compound, epidemiology, and self-assessment

Impact of annual praziquantel treatment on urogenital schistosomiasis in a seasonal transmission focus in central Senegal

In Sub-Saharan Africa, urogenital schistosomiasis remains a significant public health problem, causing 150.000 deaths/year with approximately 112 million cases diagnosed. The Niakhar district is a disease hotspot in central Senegal where transmission occurs seasonally with high prevalences. The aim of this study was to determine the effect of annual treatment over 3 years on the seasonal transmission dynamics of S. haematobium in 9 villages in the Niakhar district. Adults and children aged between 5 and 60 years were surveyed from 2011 to 2014. Urine samples were collected door-to-door and examined for S. haematobium eggs at baseline in June 2011, and all participants were treated in August 2011 with PZQ (40 mg/kg). After this initial examination, evaluations were conducted at 3 successive time points from September 2011 to March 2014, to measure the efficacy of the annual treatments and the rates of reinfection. Each year, during the transmission period, from July to November-December, malacological surveys were also carried out in the fresh water bodies of each village to evaluate the infestation of the snail intermediate hosts. At baseline, the overall prevalence of S. haematobium infection was 57.7%, and the proportion of heavy infection was 45.3%, but one month after the first treatment high cure rates (92.9%) were obtained. The overall infection prevalence and proportion of heavy infection intensities were drastically reduced to 4.2% and 2.3%, respectively. The level of the first reinfection in February-March 2012 was 9.5%. At follow-up time points, prevalence levels varied slightly between reinfection and treatment from 9.5% in June 2012 to 0.3% in March 2013, 11.2 in June 2013, and 10.1% April 2014. At the end of the study, overall prevalence was significantly reduced from 57.7% to 10.1%. The overall rate of infested Bulinid snails was reduced after repeated treatment from 0.8% in 2012 to 0.5% in 2013. Repeated annual treatments are suggested to have a considerable impact on the transmission dynamics of S. haematobium in Niakhar, due to the nature of the epidemiological system with seasonal transmission. Thus, to maintain this benefit and continue to reduce the morbidity of urogenital schistosomiasis, other approaches should be integrated into the strategy plans of the National program to achieve the goal of urogenital schistosomiasis elimination in seasonal foci in Senegal