272 research outputs found
Les espaces de l'halieutique
Les variations spatio-temporelles d'abondance du stock de bobo de GuinĂ©e sont analysĂ©es sur la pĂ©riode 1985/98 par trois catĂ©gories d'approches complĂ©mentaires. PremiĂšrement, une Ă©valuation du stock est conduite par les mĂ©thodes d'analyse de cohorte et de rendement par recrue, en s'appuyant sur les statistiques de captures disponsibles pour la pĂ©riode rĂ©cente (96/98). DeuxiĂšmement, des indices annuels de densitĂ© sont calculĂ©s par modĂ©lisation linĂ©aire des donnĂ©es des campagnes de chalutages scientifiques, rĂ©alisĂ©es depuis 1985 dans les strates bathymĂ©triques de 5 Ă 30 m. Enfin, l'estimation des surfaces des strates permet de mettre en cohĂ©rence ces deux types de rĂ©sultats et d'estimer un modĂšle de rĂ©partition des biomasses en dĂ©but et fin de pĂ©riode, dans l'ensemble des strates de 0 Ă 30 m. Dans la pĂ©riode rĂ©cente, la biomasse du stock est estimĂ©e Ă environ 9000 tonnes ; l'exploitation, trĂšs majoritairement liĂ©e Ă la pĂȘche artisanale, conduirait Ă une situation globale de pleine exploitation. Les indices de densitĂ© montrent une forte diminution de l'abondance du bobo, entre dĂ©but et fin de pĂ©riode. Cette diminution est particuliĂšrement marquĂ©e dans les strates de forte abondance, entre 5 et 10 M. Le modĂšle de rĂ©partition des biomasses, montre qu'une part essentielle du stock (probablement supĂ©rieure Ă 75%) se situe dans la strate la plus cĂŽtiĂšre (0 Ă 5m) qui Ă©chappe au navire ocĂ©anographique. La biomasse de dĂ©but de pĂ©riode, qui correspondait Ă une situation proche de l'Ă©tat vierge, est estimĂ©e Ă environ 18 000 tonnes. Le dĂ©veloppement de l'exploitation s'est ainsi traduit par une baisse d'abondance, avec un impact qui s'avĂšre ĂȘtre diffĂ©rent selon les strates bathymĂ©tiques. On met ainsi en Ă©vidence une rĂ©traction du stock sur la zone la plus cĂŽtiĂšre. (RĂ©sumĂ© d'auteur
Foraging is determinant to improve smallholdersâ food security in rural areas in Mali, West Africa
Studies on the enabling factors for household food security (HFS) most often used simplified econometric models looking into the links with a selected set of variables. In this research, a livelihood approach of HFS was used and aimed at determining the most significant livelihood assets for HFS in dryland agricultural systems. Elements of the five livelihood assets were assessed through questionnaire surveys with a random sample of 180 households, and six focus group discussions in three communities along the rural-urban continuum, in Southern Mali. The coping strategy index approach was used to evaluate household food security status. Non-parametric and parametric statistical tests were combined, as appropriate, to identify the most significant determinants of HFS status. Findings indicated that most determinant factors of HFS were the diversity of wild and cultivated food plants, and hunting (natural capital); access to clean water and irrigation (infrastructural capital); and off-farm employment (financial capital). HFS also improved along the urban-rural continuum and rural households with high natural capital seemed to be more food secure. Findings call for important investment to expand the natural capital (e.g., domestication of new crops and agricultural diversification) and infrastructural capital (irrigation facilities, clean water) of the rural households
Lymphome CĂ©rĂ©bral Primitif (LCP) du Sujet ImmunocompĂ©tent: A Propos dâUn cas Ă lâHĂŽpital National de Niamey (HNN)
Le Lymphome CĂ©rĂ©bral Primitif (LCP) du sujet immunocompĂ©tent est une entitĂ© rare des lymphomes Non Hodgkiniens en gĂ©nĂ©ral et des tumeurs cĂ©rĂ©brales en particulier. Il est caractĂ©risĂ© par sa sĂ©vĂ©ritĂ© clinique, mais aussi son mauvais pronostic. Nous rapportons un cas de LCP chez un sujet immunocompĂ©tent diagnostiquĂ© au service de neurologie et pris en charge au service dâOnco-hĂ©matologie de lâHĂŽpital National de Niamey.
Primary Cerebral Lymphoma (PCL) of the immunocompetent subject is a rare feature of non-Hodgkin's lymphoma in general and brain tumors in particular. It is characterized by its clinical severity, but also its poor prognosis. We report a case of LCP in an immunocompetent subject diagnosed in the neurology department and managed by Onco-hematology at the National Hospital of Niamey
Lymphome CĂ©rĂ©bral Primitif (LCP) du Sujet ImmunocompĂ©tent: A Propos dâUn cas Ă lâHĂŽpital National de Niamey (HNN)
Le Lymphome CĂ©rĂ©bral Primitif (LCP) du sujet immunocompĂ©tent est une entitĂ© rare des lymphomes Non Hodgkiniens en gĂ©nĂ©ral et des tumeurs cĂ©rĂ©brales en particulier. Il est caractĂ©risĂ© par sa sĂ©vĂ©ritĂ© clinique, mais aussi son mauvais pronostic. Nous rapportons un cas de LCP chez un sujet immunocompĂ©tent diagnostiquĂ© au service de neurologie et pris en charge au service dâOnco-hĂ©matologie de lâHĂŽpital National de Niamey.
Primary Cerebral Lymphoma (PCL) of the immunocompetent subject is a rare feature of non-Hodgkin's lymphoma in general and brain tumors in particular. It is characterized by its clinical severity, but also its poor prognosis. We report a case of LCP in an immunocompetent subject diagnosed in the neurology department and managed by Onco-hematology at the National Hospital of Niamey
Genetic Diversification and Selection Strategies for Improving Sorghum Grain Yield Under Phosphorous-Deficient Conditions in West Africa
Sorghum, a major crop for income generation and food security in West and Central Africa, is predominantly grown in low-input farming systems with serious soil phosphorus (P) deficiencies. This study (a) estimates genetic parameters needed to design selection protocols that optimize genetic gains for yield under low-phosphorus conditions and (b) examines the utility of introgressed backcross nested association mapping (BCNAM) populations for diversifying Malian breeding materials. A total of 1083 BC1F5 progenies derived from an elite hybrid restorer âLata-3â and 13 diverse donor accessions were evaluated for yield and agronomic traits under contrasting soil P conditions in Mali in 2013. A subset of 298 progenies were further tested under low-P (LP) and high-P (HP) conditions in 2014 and 2015. Significant genetic variation for grain yield was observed under LP and HP conditions. Selection for grain yield under LP conditions was feasible and more efficient than the indirect selection under HP in all three years of testing. Several of the BCNAM populations exhibited yields under LP conditions that were superior to the elite restorer line used as a recurrent parent. The BCNAM approach appears promising for diversifying the male parent pool with introgression of diverse materials using both adapted Malian breed and unadapted landrace material from distant geographic origins as donors
Driving Under the Influence of Drugs: A Single Parallel Monitoring-Based Quantification Approach on Whole Blood.
Driving under the influence of psychoactive substances is a major cause of motor vehicle crashes. The identification and quantification of substances most frequently involved in impaired-driving cases in a single analytic procedure could be an important asset in forensic toxicology. In this study, a highly sensitive and selective liquid chromatography (LC) approach hyphenated with Orbitrap high-resolution mass spectrometry (HRMS) was developed for the quantification of the main drugs present in the context of driving under the influence of drugs (DUID) using 100 ÎŒL of whole blood. This procedure involves a simple sample preparation and benefit from the selectivity brought by parallel reaction monitoring (PRM) allowing to solve most DUID cases using a single multi-analyte injection. The method was fully validated for the quantification of the major classes of psychoactive substances associated with impaired-driving (cannabinoids, cocaine and its metabolites, amphetamines, opiates and opioids, and the major benzodiazepines and z-drugs). The validation guidelines set by the "SociĂ©tĂ© Française des Sciences et des Techniques Pharmaceutiques" (SFSTP) were respected for 22 psychoactive substances using 15 internal standards. Trueness was measured to be between 95.3 and 107.6% for all the tested concentrations. Precision represented by repeatability and intermediate precision was lower than 12% while recovery (RE) and matrix effect (ME) ranged from 49 to 105% and from -51 to 3%, respectively. The validated procedure provides an efficient approach for the simultaneous and simple quantification of the major drugs associated with impaired driving benefiting from the selectivity of PRM
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