1,249 research outputs found
Biomass production and management practices in mixed crop-livestock systems in the west African Sahel: Opportunities and constraints
The Sahel is characterized by a marked inter-annual climate variability and has experienced a number of food security crises following the severe droughts during the 1970s and 1980s. Due to recent challenges such as rapid population growth, climate change, environmental concerns and market changes which cause major impacts to their production systems, the sahelian people have been shifting and adapting their production systems and the way they live to cope with uncertainties. The objective of the present report is to review the various biomass production and management issues in the mixed crop-livestock systems in West African Sahel. An elaborated literature survey of peer reviewed papers mostly, was conducted. The studies were based on the Sahel scale research, more specifically research that had been published on the West African Sahel, including studies published between 1990s and 2016. Results show that many factors have contributed to the changes, among which, rainfall variability, population growth, human induced-activities, land tenure systems and the effects of globalization. Various biomass production and management practices are employed in West African Sahel for both on-farm and off-farm biomass improvements. Some of the best practices are mulching, soil and water conservation techniques, composting, farmer managed natural regeneration, agroforestry, etc. These practices have overall contributed to increase agricultural productivity, ecosystem services provisioning and have sometime deepened the difference between men and women, rich and poor, young and old people. Most of the constraints associated with large adoption of the best practices in the Sahel are land tenure systems, the huge gap between inputs and output investment costs but, the climate conventions are offering new opportunities that will ultimately contribute to positive changes. This will be possible only when land tenure systems in the region are reinforced, institutional linkages are strengthened, and new information systems are used to inform farmers on climate issues and new agricultural practices
Perceptions, usages et vulnérabilité des ressources végétales ligneuses dans le Sud-Ouest du Burkina Faso
Au Burkina Faso, les populations rurales dépendent fortement des ressources végétales ligneuses pour la satisfaction de leurs besoins quotidiens. Dans un contexte de pression anthropique croissante, l’évaluation de la vulnérabilité des espèces s’avère un impératif majeur pour permettre la préservation et la gestion durable de ces ressources. Pour ce faire, des enquêtes semi-structurées ont été menées chez les Sénoufo, un des groupes ethniques dominants du Sud-Ouest du Burkina Faso. La vulnérabilité des espèces citées par les personnes enquêtées a été évaluée sur la base d’un indice de vulnérabilité (Iv) établi à partir de six paramètres. Au total, 73 espèces ont été citées pour lesquelles l’artisanat, le bois de feu et la construction se révèlent être les principales causes de vulnérabilité. Certains aspects des croyances traditionnelles s’avèrent cependant favorables à la conservation des ressources végétales ; ainsi, par exemple, certaines espèces sont interdites à la combustion. Cette étude montre que la combinaison des inventaires de terrain et des enquêtes ethnobotaniquesest indispensable comme approche fiable pour l’identification des espèces menacées
Numerical two-dimensional natural convection in an air filled square enclosure, tilted (25° and 65°) in relation to the horizontal plane, heated from two opposite sides for rayleigh numbers ranging between 103 and 2.106
Steady and transient laminar two-dimensional natural convection of a Newtonian fluid in an inclined square enclosure was numerically investigated. The enclosure was heated on the opposite sides while it was cooled on the other two sides. The inclined angles were 25° and 65° to the horizontal plane. The effect of Rayleigh numbers ranging between 103 and 2.106 on the flow development and heat transfer was studied. It was found that Nusselt number increases with the increase of Rayleigh number. Under low Rayleigh numbers the numerical studies predict the onset of stationary bicellular flow. The study showed that when the Rayleigh number was increased, an overcritical Hopf bifurcation transformed the fixed point to a limit cycle and the steady-state flow becoming oscillatoryKEYWORDS: Natural Convection, Closed Enclosure, Bifurcations, Limit Point, Limit Cycle, Tilt Angle
Knowledge and practice of emergency contraception among female students of public university of Ouagadougou, Burkina Faso, West Africa
Background: Female students are exposed to unsafe sex, sources of unwanted pregnancy and abortions. It is recognized that emergency contraception can effectively prevent pregnancy. The purpose of this study was to evaluate the knowledge and practices of Ouagadougou public university students in relation to emergency contraception in order to propose solutions to reduce the proportion of unwanted pregnancies among female students.Methods: This was a cross-sectional study conducted between May 1st and October 31st, 2016 in the public universities of Ouagadougou. A questionnaire was administered to a sample of 732 students randomly selected.Results: The average age of female students was 22.7 years old. The age group 19 to 24 was the most represented (68.03%). Of the students surveyed, 87% knew or had heard of emergency contraception. The students only used the emergency contraceptive pill. The emergency contraceptive use rate was 44.42%. Approximately, 83% of users were aware of the delay in using emergency contraception. The reasons for using emergency contraception were condom breakage (25.10%) and unprotected sex (74.9%). Female students purchased the contraceptive directly in pharmacies (93.61%).Conclusions: Emergency contraception gives women a last chance to avoid an unwanted pregnancy after unprotected sex. Awareness and free availability of emergency contraception (EC) could improve the reproductive health of female students
Hernie diaphragmatique post-traumatique de l’enfant: à propos d’un cas au Centre Hospitalier Universitaire Pédiatrique Charles de Gaulle de Ouagadougou
La hernie diaphragmatique post-traumatique est une urgence chirurgicale rare chez l’enfant mais pouvant mettre rapidement en jeu le pronosticvital. Les auteurs rapportent le cas d’un garçon de 04 ans admis aux urgences pour douleur abdominale suite à une contusion thoraco-abdominale par accident de la voie publique. Le bilan radiologique initial a consisté en une échographie abdominale qui a révélé un hémopéritoine de petite abondance sans lésion focale. Douze heures après son admission, le patient a présenté une détresse respiratoire avec tableau clinique depneumothorax gauche qui a nécessité une exsufflation en urgence. Le diagnostic de hernie diaphragmatique gauche a été posé à la radiographiedu thorax réalisée après la ponction. L’enfant a bénéficié d’une cure chirurgicale. L’évolution a été favorable. La hernie diaphragmatique posttraumatique, bien que rare chez l’enfant, devrait être systématiquement recherchée par une radiographie thoracique ou un scanner thoracoabdominal devant tout traumatisme abdominal avec hyper pression. Son traitement est chirurgical
Diversité et structure des cordons ripicoles le long de la sirba (Nord-Est du Burkina Faso)
Les Cordons ripicoles sont des végétations bordant les rivières à   écoulement temporaire et qui possèdent des sols riches et une grande capacité en bois. Ces ressources sont anarchiquement utilisées par l’homme créant ainsi la fragmentation des berges. Cette étude s’inscrit dans le cadre d’une évaluation de la diversité et de la structure des cordons ripicoles en fonction de l’orientation de l’écoulement (amont, zoneintermédiaire, aval) et par rapport à la savane adjacente du cours d’eau temporaire la Sirba. L’analyse de 218 relevés dendrométriques ont montré que la richesse spécifique et la diversité sont plus élevées dans les savanes adjacentes. Il existe néanmoins un important potentiel en bois dans les cordons ripicoles révélé par une surface terrière moyenne forte (27,32 m²/ha) et une densité forte. La richesse spécifique, l’indice d’importance des espèces (IVI), celui d’importance des familles (FIV) et la diversité sont significativement différentes dans les trois positions d’écoulement. La prédominance des Rubiaceae dans la zone intermédiaire traduit une meilleure inondation de ce site. La structure des cordons ripicoles, des savanes adjacentes et des espèces écologiquement importantes est relativement stable. Cependant, la densité faible des individus juvéniles laisse voir un problème de régénération de ces écosystèmes.© 2013 International Formulae Group. All rights reserved.Mots clés: Etat, Phytodiversité, cours d’eau temporaire, écoulement, dégradation des berges, Sahel
Public-private partnership for inclusive sanitation in informal and peri-urban areas of Ouagadougou
21% of the total population of the capital city live in settlements in peri urban areas of Ouagadougou which are illegal and informal and hence, pose a challenge to the traditional way of delivering basic services in urban areas. Around 94% of this population lack access to improved latrines and nearly 19% practice open defecation. As a result, water borne diseases are the main cause of consultations in health centres. To improve access to sanitation, WaterAid has worked with the municipality of Ouagadougou and the water utility, to initiate a project allowing private operators to provide informal settlements with the same services as the formal sectors. The project helped move the household sanitation access rate from 6.1% to 9.4% in 3 years. The learning gathered provides insights into the institutionalization and sustainability of this approach as a means to achieve universal access to sanitation
HPLC ANALYSIS AND ANTI-INFLAMMATORY PROPERTIES STUDIES OF TRUNK BARKS OF ACACIA NILOTICA VAR ADANSONII (GUILL AND PERR) O KTZE (MIMOSACEAE)
Objective: The objective of this study was to evaluate the in vitro and in vivo anti-inflammatory properties of the aqueous extract and fractions of the trunk bark of Acacia nilotica.
Methods: A maceration of the powder of the trunks barks of the plant was realized. Then the aqueous macerate obtained was fractionated with dichloromethane, butanol and ethyl acetate successively. The phenolic compounds of the aqueous extract, butanol and ethyl acetate fractions were identified by HPLC/DAD. Lipoxygenase and phospholipase inhibition tests with the aqueous extract and the butanol and ethyl acetate fractions were carried out. The anti-inflammatory potential of the aqueous extract was assessed in vivo by the anti-edema test with carrageenan and the analgesic test with acetic acid at different doses (200 mg/ml; 400 mg/ml; 600 mg/ml). Aspirin (200 mg/ml) and paracetamol (200 mg/ml) were used as a reference.
Results: The HPLC/DAD analysis of the extracts revealed that gallic acid is the most abundant phenol acid in the extracts. The aqueous extract inhibited lipoxygenase (IC50 = 18.32±1.18 μg/ml), phospholipase (11.44±0.32% per 100 μg/ml) and cyclooxygenase (56.48±0.29% for 100 μg/ml) as well as its tested fractions. It also reduced edema and pain in the mice by more than 50% from the 400 mg/ml dose.
Conclusion: Aqueous extract of Acacia nilotica has anti-inflammatory properties. Hence its use in traditional medicine in the treatment of inflammation
Etude des stades préimaginaux de culicidés dans des gîtes de petites et grandes dimensions dans le Sud-Ouest de la Haute-Volta
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