Etude Comparative de l’effet de Souches de Champignons Mycorhiziens Arbusculaires sur la Croissance et la Nutrition Minérale du Sésame Cultivé au Sénégal

La croissance et la nutrition minérale de huit variétés locales de Sésame (Sesamum indicum L.) ont été évaluées en réponse à l’inoculation mycorhizienne arbusculaire. Les essais conduits en serre pendant trois mois, ont montré un meilleur développement et une meilleure nutrition minérale chez les plants inoculés comparé aux témoins non inoculés. Les variétés testées se sont révélées très dépendantes de la mycorhization arbusculaire. Le degré de dépendance est généralement supérieur à 55 % et est fortement corrélé à l’isolat fongique et à la variété testée. Il ressort de cette étude que les biofertilisants à base de champignons mycorhiziens procurent des bénéfices importants à la plante, et peuvent être utilisés pour améliorer la croissance et le rendement du sésame.Mots Clés: Biofertilisation, Mycorhizienne, Sesamum indicumThe growth and mineral nutrition of eight local varieties of Sesame (Sesamum indicum L.) were evaluated in response to arbuscular mycorrhiza inoculation in a greenhouse. There was greater plant growth and better mineral nutrition in inoculated pots compared to non-inoculated controls. The varieties tested showed high dependence on arbuscular mycorrhiza. The degree of dependence was generally greater than 55% and was highly correlated with the fungal isolates and variety tested. It is evident that mycorrhizae fungi-based biofertilisers provide significant benefits to the plant and can be used to improve growth and yield in sesame.Keywords: Biofertilisation, Mycorrhiza, Sesamum indicu

Facteurs de risque de démence dans une population de personnes âgées sénégalaises

Description La démence est devenue un problème de santé publique. Dans le but d’une prévention, il est important de connaitre son épidémiologie au Sénégal. L’objectif de cette étude était d’identifier les facteurs de risque de démence dans une population de personnes âgées sénégalaises. MéthodesUne étude transversale a été réalisée du 01 Mars 2004 au 31 Décembre 2005 auprès d’une population de 872 personnes âgées de 55ans et plus utilisant le Centre Médicosocial et Universitaire de l’Institut de Prévoyance Retraite du Sénégal pour des soins. Par une étude en deux phases, des données sociodémographiques, sur le mode de vie, le réseau social, les antécédents ont été collectées à l’aide d’un questionnaire structuré complété par un examen clinique et une évaluation neuropsychologique. Le diagnostic de démence reposait sur des critères DSM IV-R

Caractérisation agropédologique des sols de mboltime dans la zone des niayes (Sénégal)

L'objectif de cette étude était de faire une évaluation de la fertilité physico-chimique de différents sols du village de Mboltime et de déterminer les similarités relatives. Les horizons de cinq fosses pédologiques (P1 , P2, P3, P4 et P5) ouvertes dans les zones dunaires et inter-dunaires ont servi à cet effet. Les résultats obtenus ont montré que les horizons de surface sont sableux à sablo-limoneux avec des pH et conductivité électrique variant selon les profils et les horizons. Seul le profil P4 a montré des sols acides et salés au niveau des horizons P4H1, P4H3 et P4H5. Les autres profils ont montré des sols neutres à légèrement alcalins et non salins. Les teneurs en matière organique et azote total ont été assez faibles dans les profils 1, 2, 3 et 5, et moyens dans le profil 4 avec un rapport C/N variant de 2,72 à 16,50. Les teneurs en Ca2+, Mg2+, Na+ et K+ varient suivant le C et N. Le cation le plus abondant dans les sols a été le Ca2+; suivi du Mg2+ et du Na+ alors que K+ a été le cation le moins abondant. L'analyse factorielle des correspondances (AFC) a permis de mettre en évidence deux groupes de sols en fonction de la salinité et de l'acidité. Un groupe I constitué de sols très salins et un groupe II constitué de sols non salins. Cette étude a mis en évidence deux contraintes majeures à la production végétale dans le village de Mboltime que sont la salinité et l'acidité des sols.Mots clés : Sol, Profil pédologique, Niayes, salinite ; Sénégal AGROPEDOLOGICAL CARACTERIZATION OF MBOLTIME SOILS IN NIAYES AREA (SENEGAL)The objective of this study was to evaluate physico - chemical properties of different soils from Mboltime village and relevant similarities. Horizons of five soil profiles (P1, P2, P3, P4 and P5) in the dune and inter-dune areaswere used for that purpose. The results showed variance in topsoil contents of sand with silt- loam, pH and electric conductivity according to the  profiles. Only the P4 profile presents acid and salty soil to the level asof horizons P4H1, P4H3 and P4H5. The other profiles presented neutral to slightly alkaline soil pH with limited salinity. The soil contents of organic matter, and total nitrogen were rather weak in the profiles 1, 2, 3 and 5, and moderate in profile 4. The C/N ratio values varied from 2.72 to 16.50 while soil contents of Ca2+, Mg2+, Na+ and K+ variations were according to C and N. The most abundant cations in land was Ca2+; followed by Mg2+, Na+ and K+ was the least abundant cationin soils. The factorial  correspondence analysis (FCA) showed two groups of soil according to  salinity and acidity mainly depending to high and low salinity respectively. This study showed two major constraints to land productivity in the village of Mboltime which are the salinity and the acidity of soils.Keywords : Soil, soil profile, salinity, Niayes, Senega

Electron Accumulation and Emergent Magnetism in LaMnO3/SrTiO3 Heterostructures

Emergent phenomena at polar-nonpolar oxide interfaces have been studied intensely in pursuit of next-generation oxide electronics and spintronics. Here we report the disentanglement of critical thicknesses for electron reconstruction and the emergence of ferromagnetism in polar-mismatched LaMnO3/SrTiO3 (001) heterostructures. Using a combination of element-specific X-ray absorption spectroscopy and dichroism, and first-principles calculations, interfacial electron accumulation and ferromagnetism have been observed within the polar, antiferromagnetic insulator LaMnO3. Our results show that the critical thickness for the onset of electron accumulation is as thin as 2 unit cells (UC), significantly thinner than the observed critical thickness for ferromagnetism of 5 UC. The absence of ferromagnetism below 5 UC is likely induced by electron over-accumulation. In turn, by controlling the doping of the LaMnO3, we are able to neutralize the excessive electrons from the polar mismatch in ultrathin LaMnO3 films and thus enable ferromagnetism in films as thin as 3 UC, extending the limits of our ability to synthesize and tailor emergent phenomena at interfaces and demonstrating manipulation of the electronic and magnetic structures of materials at the shortest length scales.Comment: Accepted by Phys. Rev. Let

Stability of Mine Car Motion in Curves of Invariable and Variable Radii

We discuss our experiences adapting three recent algorithms for maximum common (connected) subgraph problems to exploit multi-core parallelism. These algorithms do not easily lend themselves to parallel search, as the search trees are extremely irregular, making balanced work distribution hard, and runtimes are very sensitive to value-ordering heuristic behaviour. Nonetheless, our results show that each algorithm can be parallelised successfully, with the threaded algorithms we create being clearly better than the sequential ones. We then look in more detail at the results, and discuss how speedups should be measured for this kind of algorithm. Because of the difficulty in quantifying an average speedup when so-called anomalous speedups (superlinear and sublinear) are common, we propose a new measure called aggregate speedup

20/20 Vision - What does the next 20 years hold for citizenship education?

Citizenship is a feeling, status and practice. It is essentially about living together and working to transform society towards greater democracy and social justice. It is a curriculum space shared by educational movements for human rights, political literacy, sustainable development, peace and equalities. Implementing this synthesis of politics, philosophy, sociology, law and international relations is an adventure in curriculum development. I identify three periods of Citizenship in England, analysing opportunities and significant and severe threats now and in the future

The Incremental Cooperative Design of Preventive Healthcare Networks

This document is the Accepted Manuscript version of the following article: Soheil Davari, 'The incremental cooperative design of preventive healthcare networks', Annals of Operations Research, first published online 27 June 2017. Under embargo. Embargo end date: 27 June 2018. The final publication is available at Springer via http://dx.doi.org/10.1007/s10479-017-2569-1.In the Preventive Healthcare Network Design Problem (PHNDP), one seeks to locate facilities in a way that the uptake of services is maximised given certain constraints such as congestion considerations. We introduce the incremental and cooperative version of the problem, IC-PHNDP for short, in which facilities are added incrementally to the network (one at a time), contributing to the service levels. We first develop a general non-linear model of this problem and then present a method to make it linear. As the problem is of a combinatorial nature, an efficient Variable Neighbourhood Search (VNS) algorithm is proposed to solve it. In order to gain insight into the problem, the computational studies were performed with randomly generated instances of different settings. Results clearly show that VNS performs well in solving IC-PHNDP with errors not more than 1.54%.Peer reviewe

Assessing the impact of integrated community-based management of severe wasting programs in conflict-stricken south Sudan : a multi-dimensional approach to scalability of nutrition emergency response programs

Community-based management of severe wasting (CMSW) programs have solely focused on exit outcome indicators, often omitting data on nutrition emergency preparedness and scalability. This study aimed to document good practices and generate evidence on the effectiveness and scalability of CMSW programs to guide future nutrition interventions in South Sudan. A total of 69 CMSW program implementation documents and policies were authenticated and retained for analysis, complemented with the analyses of aggregated secondary data obtained over five (2016–2020 for CMSW program performance) to six (wasting prevention) years (2014–2019). Findings suggest a strong and harmonised coordination of CMSW program implementation, facilitated timely and with quality care through an integrated and harmonised multi-agency and multidisciplinary approach. There were challenges to the institutionalisation and ownership of CMSW programs: a weak health system, fragile health budget that relied on external assistance, and limited opportunities for competency-based learning and knowledge transfer. Between 2014 and 2019, the prevalence of wasting fluctuated ac-cording to the agricultural cycle and remained above the emergency threshold of 15% during the July to August lean season. However, during the same period, under-five and crude mortality rates (10,000/day) declined respectively from 1.17 (95% confidence interval (CI): 0.91, 1.43) and 1.00 (95% CI: 0.75, 1.25) to 0.57 (95% CI: 0.38, 0.76) and 0.55 (95% CI: 0.39, 0.70). Both indicators remained below the emergency thresholds, hence suggesting that the emergency response was under control. Over a five-year period (2016–2020), a total of 1,105,546 children (52% girls, 48% boys) were admitted to CMSW programs. The five-year pooled performance indicators (mean [standard deviations]) was 86.4 (18.9%) for recovery, 2.1 (7.8%) for deaths, 5.2 (10.3%) for defaulting, 1.7 (5.7%) for non-recovery, 4.6 (13.5%) for medical transfers, 2.2 (4.7%) for relapse, 3.3 (15.0) g/kg/day for weight gain velocity, and 6.7 (3.7) weeks for the length of stay in the program. In conclusion, all key performance indicators, except the weight gain velocity, met or exceeded the Humanitarian Charter and Minimum Standards in Humanitarian Response. Our findings demonstrate the possibility of implementing robust and resilient CMSAM programs in protracted conflict environments, informed by global guidelines and protocols. They also depict challenges to institutionalisation and ownership

Case study of Daga-Birame CSV for CCAFS ISP11/6.1.2 – Senegal

Senegal, with 196,712 km2 land area, is located at the extreme west of the African continent (Longitudes 11°21W - 17°32N and Latitudes 12°8N - 16°41N). The country’s soils are in general of low fertility, fragile and very susceptible to wind and water erosion. The climate is of Sudano-Sahelian type characterized by alternating dry season (November to May) and rainy season (June to October). The 700 km coastline brings climatic differences between coastal areas and inland zones. Rainfall amount follows a latitudinal variation going from 300 mm in the north semi-desertic areas to 1200 mm in the south. Senegal is divided into 7 agro-ecological zones for management perspectives: River Valley, Niayes, Groundnut Basin (North and South), Silvo-Pastoral zone, Eastern Senegal and Upper Casamance, Lower Casamance (CIAT-BFS/USAID, 2016). The country’s economy is mainly driven by crop and livestock production contributing 17% of the GDP and employing about 70% of the population (NAPA, Republic of Senegal 2006). Like other sub-Saharan African countries, Senegal faces food insecurity as a consequence of climate variability and change combined with other global changes (Zougmoré et al., 2015)