Mesure de la production de beauté dans les collisions Pb-Pb centrales au LHC à l'aide du spectromètre à muons du détecteur ALICE

Stage Janus- responsable Rachid Guernan

Identification des risques climatiques de la culture du maïs au Burkina Faso

Au Burkina Faso, le maïs est cultivé dans les zones soudaniennes et soudano-sahéliennes où les conditions pluviométriques sont plus favorables. La culture est sensible aux aléas climatiques liés à la variabilité et aux extrêmes pluviométriques. L’objectif de l’étude est d’identifier les risques climatiques pour la culture du maïs. A partir des données météorologiques journalières, une analyse agroclimatique a été réalisée sur la période 1979-2008 sur six stations synoptiques. A l’aide du logiciel Instat+ v 3.036, la variabilité des précipitations et des paramètres clés de la saison agricole dont les dates de démarrage, de fin, la longueur de la saison, les occurrences de séquences sèches et la satisfaction des besoins en eau ont été analysés en termes de risques d’apparition. Les résultats ont montré que le maïs est confronté à deux risques agroclimatiques majeurs. Il s’agit, dans la zone soudano-sahélienne, des déficits hydriques imputables à des séquences sèches au cours du développement du maïs. Tandis que les excès d’eau liés à des fortes pluies ou des successions d’épisodes secs et d’excès d’eau constituent les risques en zone soudanienne. La période d’installation, le cumul pluviométrique, la longueur de la saison ne semblent pas constituer de risques agroclimatiques majeurs pour le maïs.Keywords: Maïs pluvial, variabilité pluviométrique, paramètres saison agricole, déficit hydrique, excès d’ea

Effet de deux types d’insecticides sur la mycorhization arbusculaire et le développement de deux variétés de pomme de terre (Solanum tuberosum)

Cette étude a été menée en serre pour évaluer l’effet de deux types d’insecticides sur la mycorhization et le développement de deux variétés de pomme de terre (Aïda et Atlas). Les insecticides carbofuran et chlorpyriphos-éthyl, respectivement systémiques et contacts, ont été appliqués au sol à différentes stades d’inoculation du champignon Glomus mosseae. Le pourcentage de mycorhization, la biomasse aérienne, lenombre et le calibre des minitubercules ont été évalués après 60 jours de culture. L’application du carbofuran ou du chlorpyriphos-éthyl 21 jours avant ou après l’inoculation du champignon induit une diminution significative du pourcentage de colonisation mycorhizienne chez toutes les deux variétés. Cependant, cette baisse est plus importante avec les  traitements de l’insecticide de contact après inoculation et de l’insecticidesystémique effectué avant inoculation. Cette tendance s’est répercutée sur la biomasse aérienne et le nombre des minitubercules. Le calibre des minitubercules présente une variabilité de réponse selon la variété de pomme de terre et le type d’insecticide. Ce travail a permis de déterminer le moment compatible de l’inoculation de Glomus mosseae avec  l’application des insecticides au sol chez les variétés Aïda et Atlas de la pomme de terre.© 2013 International Formulae Group. All rights reserved.Mots clés: Glomus mosseae, carbofuran, chlorpyriphos-éthyl, Aïda, Atlas

Pour une agriculture intelligente face au changement climatique au Sénégal: Recueil de bonnes pratiques d'adaptation et d'atténuation

Climate change is at the present time a new threat which leads to increased frequency and intensity of floods, droughts and cyclones with rising sea levels; thus placing additional demands on a situation already critical in rural areas. In Senegal, as in many countries of the Sahel, those natural phenomena result in a significant drop in harvests, water shortages and worsening health crisis which leads to consequences such as growing food insecurity of the population; thus threatening the progress achieved in regards with the fight against poverty during the last century. Indeed, many farmers live in rural areas which are characterized as low rainfall, saline soils, fragile or degraded soils and limited market access areas. The poverty in which they live, especially those of women, is often worsened by social exclusion. Such farmers are vulnerable because they depend directly on rainfall and seasons. They have little savings while supports from the government or their local authorities remain inadequate. It is essential to strengthen the adaptive capacity of vulnerable countries and communities to cope with the impacts of climate change on agriculture and food security. This document is the result of a multi-criteria analysis of experiences of tackling climate variability, drought and desertification, and land degradation on one hand, and Adaptation to Climate Change in Senegal on the other. It is carried out on the initiative of the national platform for science-policy dialogue on adaptation of agriculture and food security to climate change (C-CASA) for capacity building and informed decision making for adaptation to climate change. This work has received technical and financial support from CCAFS Program (www.ccafs.cgiar.org). It is intended for the use of field workers in the area of adaptation to climate change. It also serves as technologies and tools guide to adapt to climate change impacts in the area of agriculture and food security. The manual is based primarily on (1) both the institutional and peasant experiences of the actors; (2) the recommendations of the reports of the Inter-governmental Panel on Climate Change (IPCC); (3) the procedures manual for assessing climate change impacts and adaptation strategies; (4) the results of development projects and applied research. This is a collection that comes as a complement to other initiatives in the country and ongoing operations which provide practical examples of using the technological options for successful implementation of projects and programs and for the definition of agricultural policies in the Sahel

Responses of potatoes plants inoculated with arbuscular mycorrhizal fungi and litter in greenhouse

A pot experiment was set to examine the impact of the foliar litter (Hardwickia binata and Azadirachta indica) and an arbuscular mycorrhizal (AM) fungus on the development of two varieties of potato plants (Aida, Atlas). Three litter doses (0, 25 and 50 g) were applied to the pots after bedding plantlets. The plants were inoculated with AM, Glomus aggregatum. Mycorrhizal colonization, shoot dry weight, size and number of minitubers were evaluated after 12 weeks on the potato growth. Results show that shoot dry weight of plants was improved by litter of the H. binata at 25 and 50 g. Thus, A. indica litter increased size of plants Aida at 50 g and the minitubers numbers Atlas at 25 g. On the other hand, root colonization decreased with increase in the dose of litter with both varieties of potato.Key words: Arbuscular mycorrhizal fungi, potato, litter, micropropagation

Nutrients composition of calyces and seeds of three Roselle (Hibiscus sabdariffa L.) ecotypes from Niger

The chemical composition of calyces and seeds of three ecotypes of Roselle from Niger was compared. The results indicate that calcium (Ca), potassium (K), sodium (Na), magnesium (Mg) and protein contents in calyces are significantly different (P<0.005) among ecotypes. The highest concentrations of K, Na, Mg and protein in calyces were recorded for ecotype E7 (35.66, 3.40, 6.01 and 101 mg/g d.w., respectively). Ecotype E9 had the highest Ca content in calyces (34.41 mg/g d.w.); while E3 and E7 had similar and lower contents. The protein content in calyces for E9 (52 mg/g d.w.) was approximately halved compared to those of E3 and E7. For all ecotypes, the concentrations of Ca, K, Mn, Na and Fe in the calyces were higher compared to those in the seeds. In contrast, P content was higher in seeds. The highest K, Na, Mg and P concentrations in seeds were registered for E7 and the lowest ones for E9. Ecotypes E3 and E9 recorded higher and similar Cu, Fe and Mn contents in calyces and in seeds compared to E7. The highest Zn concentrations in seeds were obtained for E3 and E7.Keywords: Niger, Roselle, seeds, calyces, protein, composition, micronutrients, macronutrientsAfrican Journal of Biotechnology Vol. 12(26), pp. 4174-417

Development and validation of a simple and economical spectrofluorimetric method for estimation of quinine in pharmaceutical dosage forms

A new simple, sensitive, precise, economic and “green” spectrofluorimetric method for the determination of quinine both as a bulk drug and in tablet formulations was developed and validated using water as solvent. At a predetermined excitation wavelength (330 nm) and emission wavelength (380 nm), it was proved linear in the concentration range of 50-500 ng/mL, exhibited good correlation coefficient (R2= 0.999) and excellent mean recovery (97.5-103%). The results of the recovery studies showed that the method was not affected by the presence of common excipients. The method was applied for the analysis of the drug in the pure, tablet and injectable forms. The method was validated for precision, accuracy and recovery studies. Limit of Detection and Limit of Quantification for quinine were found to be 16.6 ng/mL and 19.8 ng/mL respectively. The method has been successfully applied for the analysis of marketed formulations available in Senegal. © 2013 International Formulae Group. All rights reserved.Keywords: Spectrofluorometric analysis, validation, quinine, green method

Saguache County, closed basin biological inventory. Volume I: Natural heritage assessment final report

Prepared for: The Nature Conservancy, San Luis Valley program, Saguache, Colorado.February 1998.Includes bibliographical references

Enhanced Modelling of Authenticated Key Exchange Security

The security models for Authenticated Key Exchange do not consider leakages on pre–computed ephemeral data before their use in sessions. We investigate the consequences of such leakages and point out damaging consequences. As an illustration, we show the HMQV–C protocol vulnerable to a Bilateral Unknown Key Share (BUKS) and an Unilateral Unknown Key Share (UUKS) Attack, when precomputed ephemeral public keys are leaked. We point out some shades in the seCK model in multi–certification authorities setting. We propose an enhancement of the seCK model, which uses a liberal instantiation of the certification systems model from the ASICS framework, and allows reveal queries on precomputed ephemeral (public and private) keys. We propose a new protocol, termed eFHMQV, which in addition to provide the same efficiency as MQV, is particularly suited for implementations wherein a trusted device is used together with untrusted host machine. In such settings, the non–idle time computational effort of the device safely reduces to one digest computation, one integer multiplication, and one integer addition. The eFHMQV protocol meets our security definition, under the Random Oracle Model and the Gap Diffie–Hellman assumption