Linear and nonlinear optical absorption characterization of natural laccaic acid dye

We report on the optical performances of laccaic acid dye in solution at different concentrations and dye–poly(methyl methacrylate) composite thin films. The linear spectral characteristics including optical constants, i.e. refractive index (n) and extinction coefficient (k), were carried out in a comprehensive way through absorbance, fluorescence and ellipsometric studies. The nonlinear optical parameters such as nonlinear absorption coefficient β eff (or β 2), the imaginary third-order susceptibility (Im[χ (3)]) and the imaginary part of second-order hyperpolarizability (γ) of the samples were evaluated using the open-aperture Z-scan technique with a laser pulse duration of 10 ns at 532 nm wavelength. The corresponding numerical values of these parameters were of 10−10, 10−11 and 10−32 order, respectively. Two-photon absorption was revealed to be the main driving physical mechanism in the nonlinear response. This suggests that laccaic acid dye can be a potential candidate for NLO materials application

Epilepsy and traditional medicine in Bobo-Dioulasso (Burkina Faso).

OBJECTIVES: To contribute to a better knowledge of how epilepsy is perceived by traditional healers in Burkina Faso; what means they use to treat it, and how they think about modern treatment. MATERIAL AND METHODS: Individual interviews with 65 traditional healers chosen at random from members of the Reelwende Association. RESULTS: All traditional practitioners were of male gender. Most of them were above 50 years of age, and 75% had more than 10 years' experience. Epilepsy was considered to be contagious by 44% of the traditional practitioners, and hereditary according to 40% of them. Roughly, 15% of the healers think that the problem is localized in the head of a person and 7.8% think that they have worms in their head. Thirty-one per cent of them diagnose epilepsy if there is a combination of 'convulsions, sudden fall, dribbling and amnesia'. Another 15% require a combination of 'convulsions, amnesia and dribbling', the remaining 54% make the diagnosis based on one symptom or various combinations of two symptoms of 'grand mal' (generalized tonic clonic) seizures and most claim they have a treatment for it. For a quarter of them, therapeutic-means include concoctions of herbs or roots, baths and infusions. During the fit, 31% of the traditional practitioners think that nothing should be performed. According to 75% of them, traditional and modern treatments are complementary. CONCLUSION: Notwithstanding important differences in culture and religions (Muslim, Christian and Original), there is great similarity between the knowledge and beliefs about epilepsy reported from other parts of Africa and those presented by our study-group, suggesting an ancient origin of the concepts. Further study is needed to find out how other facets of epilepsy (e.g. complex partial seizures, absences) are perceived and how these are being treated. Ways need to be found to raise awareness about epilepsy without interfering with religious and cultural beliefs

Different methodological approaches to the assessment of in vivo efficacy of three artemisinin-based combination antimalarial treatments for the treatment of uncomplicated falciparum malaria in African children.

BACKGROUND: Use of different methods for assessing the efficacy of artemisinin-based combination antimalarial treatments (ACTs) will result in different estimates being reported, with implications for changes in treatment policy. METHODS: Data from different in vivo studies of ACT treatment of uncomplicated falciparum malaria were combined in a single database. Efficacy at day 28 corrected by PCR genotyping was estimated using four methods. In the first two methods, failure rates were calculated as proportions with either (1a) reinfections excluded from the analysis (standard WHO per-protocol analysis) or (1b) reinfections considered as treatment successes. In the second two methods, failure rates were estimated using the Kaplan-Meier product limit formula using either (2a) WHO (2001) definitions of failure, or (2b) failure defined using parasitological criteria only. RESULTS: Data analysed represented 2926 patients from 17 studies in nine African countries. Three ACTs were studied: artesunate-amodiaquine (AS+AQ, N = 1702), artesunate-sulphadoxine-pyrimethamine (AS+SP, N = 706) and artemether-lumefantrine (AL, N = 518).Using method (1a), the day 28 failure rates ranged from 0% to 39.3% for AS+AQ treatment, from 1.0% to 33.3% for AS+SP treatment and from 0% to 3.3% for AL treatment. The median [range] difference in point estimates between method 1a (reference) and the others were: (i) method 1b = 1.3% [0 to 24.8], (ii) method 2a = 1.1% [0 to 21.5], and (iii) method 2b = 0% [-38 to 19.3].The standard per-protocol method (1a) tended to overestimate the risk of failure when compared to alternative methods using the same endpoint definitions (methods 1b and 2a). It either overestimated or underestimated the risk when endpoints based on parasitological rather than clinical criteria were applied. The standard method was also associated with a 34% reduction in the number of patients evaluated compared to the number of patients enrolled. Only 2% of the sample size was lost when failures were classified on the first day of parasite recurrence and survival analytical methods were used. CONCLUSION: The primary purpose of an in vivo study should be to provide a precise estimate of the risk of antimalarial treatment failure due to drug resistance. Use of survival analysis is the most appropriate way to estimate failure rates with parasitological recurrence classified as treatment failure on the day it occurs

L’effet des droits de propriété sur l’adoption des techniques de conservation des eaux et des sols par les producteurs de céréales au Burkina Faso

This article is an attempt to give an answer to the main research question entitled: what is the effect of property rights on the adoption of water and soil conservation techniques by cereal producers in Burkina Faso. The objective of this article is to evaluate the effect of property rights on the adoption of water and soil conservation techniques by cereal producers in Burkina Faso. A multivariate probit model is used on a sample of 4,813 plots from the survey carried out by the second National Land Management Program (PNGT2) in 2011 on households in Burkina Faso. The results show that formal property rights positively influence the probability of adoption of stone bunds, half-moons and hedgerows. The main conclusion of this research is that formal property rights positively influence the probability of adoption of stone bunds, half-moons and hedgerows. The article therefore recommends the use of water and soil conservation techniques by cereal producers with formal property rights over their plots.Cet article est une tentative de donner une réponse à la question principale de recherche intitulée : quel est l’effet des droits de propriété sur l’adoption des techniques de conservation des eaux et des sols par les producteurs de céréales au Burkina Faso. L’objectif de cet article est d’évaluer l’effet des droits de propriété sur l’adoption des techniques de conservation des eaux et des sols par les producteurs de céréales au Burkina Faso. Un modèle probit multivarié est utilisé sur un échantillon de 4 813 parcelles de l’enquête réalisée par le deuxième Programme National de Gestion des Terroirs (PNGT2) en 2011 sur les ménages au Burkina Faso. Les résultats montrent que les droits de propriété formels influencent positivement la probabilité d’adoption des diguettes en cordons pierreux, des demi-lunes et des haies vives. La principale conclusion de cette recherche est que les droits de propriétés formels influencent positivement la probabilité d’adoption des diguettes en cordons pierreux, des demi-lunes et des haies vives. L’article recommande par conséquent l’utilisation des techniques de conservation des eaux et des sols par les producteurs de céréales disposant de droits de propriété formels sur leurs parcelles

Caractérisation agromorphologique des accessions de riz adventices (Oryza sp) collectés dans les rizières de la zone interfluve du Tchad

Le riz est la céréale de base des populations des Régions administratives de la Tandjilé et du Mayo- Kebbi Est, dans le sud du Tchad. Le rendement du riz est cependant relativement très bas (moins de 1 t/ha). Ceci est lié à plusieurs facteurs parmi lesquels la forte infestation des rizières par les riz adventices et la faible utilisation des semences des variétés améliorées haut rendement. Parmi les mauvaises herbes, les plus fréquentes et nocives pour le riz cultivé, sont les espèces comme Oryza sativa L., Oryza barthii (A Chev) et Oryza longistaminata (A. Chev et Roehr). Celles-ci montrent une forte dynamique de l'infestation dans les rizières des plaines inondées des Régions administratives de la Tandjilé et du Mayo-Kebbi Est. La caractérisation agromorphologique de 24 échantillons riz adventices issus des opérations de prospectioncollecte d'octobre 2005 à Mars 2006 a été réalisée. A partir d’un dispositif de Ficher à trois répétitions, une expérimentation a permis de mettre en évidence, par une analyse de variance , une classification ascendante hiérarchique et l'analyse factorielle discriminante, l'existence de cinq groupes de riz adventices

Composition nutritionnelle de 10 fruits sauvages consommés dans trois départements du Tchad

Dans le sahel, les plantes sauvages font encore l’objet de cueillette par les populations rurales afin de les vendre pour subvenir à leurs besoins et de les intégrer dans leur alimentation. Les méthodes chimiques ont été utilisées pour la détermination de la valeur nutritive de ces fruits. Il ressort que les fruits secs ont les teneurs les plus élevées en sucres (les fruits de Hyphaene thebaïca Mart. : 59,78 ±0,14) et en protéine (les fruits de Parkia biglobosa (Jacq.) Benth. : 6,89%±0,15). Il n’y a pas une grande variation de la teneur en lipides entre les fruits secs et frais. L’analyse des vitamines et minéraux pour 100 g de matières sèches montrent que les fruits de Parkia biglobosa (Jacq) Benth. sont aussi les plus riches en vitamine C (208,71 mg±0,19) et en zinc (47,65 mg±0,16). Les fruits de Tamarindus indica L. ont les teneurs les plus élevées en calcium (183,25 mg±1,45) et les fruits de Balanites aegyptiaca (L.) Del. ont les teneurs les plus élevées en magnésium et en fer (respectivement 201,24 mg±1,91 et 271,98 mg±2,99). Ces résultats montrent que les fruits sauvages sont une bonne source de nutriments et par conséquent, ils peuvent faire l’objet de valorisation auprès des populations rurales.© 2015 International Formulae Group. All rights reserved.Mots clés: Fruits sauvages, cueillette, valeur nutritionnelle, TchadEnglish Title: Nutritional composition of 10 wild fruits consumed in three divisions in ChadEnglish AbstractIn the Sahel, wild fruits are still under collection by rural people in order to sell them, for their economic purpose, and integrate them in their diet. Chemical methods were used for the determination of the nutritional value of these fruits. It appears that dried fruits had the highest carbohydrate (the fruits of Hyphaene thebaica Mart.: 59.78% ±0.14) and protein (the fruits of Parkia biglobosa (Jacq.) Benth: 6.89%±0.15) contents. There was no significant variation in the fat content between dry and fresh fruits. The analysis of vitamins and minerals for 100 g of dry matter showed that the fruits of Parkia biglobosa (Jacq) Benth. are also the richest in vitamin C (208.71 mg±0.19) and zinc (47.65 mg±0.16). The fruits of Tamarindus indica L. had the highest level of calcium (183.25 mg±1.45) and the fruits of Balanites aegyptiaca (L) Del. had the highest magnesium and iron levels (respectively 201.24 mg±1.91 and 271.98 mg±2.99). These results show that wild fruits are a good source of nutrients, and therefore they are subject to valuation with rural populations.© 2015 International Formulae Group. All rights reserved.Keywords: Wild fruit, gathering, nutritional value, Cha

Globally prevalent PfMDR1 mutations modulate Plasmodium falciparum susceptibility to artemisinin-based combination therapies

Antimalarial chemotherapy, globally reliant on artemisinin-based combination therapies (ACTs), is threatened by the spread of drug resistance in Plasmodium falciparum parasites. Here we use zinc-finger nucleases to genetically modify the multidrug resistance-1 transporter PfMDR1 at amino acids 86 and 184, and demonstrate that the widely prevalent N86Y mutation augments resistance to the ACT partner drug amodiaquine and the former first-line agent chloroquine. In contrast, N86Y increases parasite susceptibility to the partner drugs lumefantrine and mefloquine, and the active artemisinin metabolite dihydroartemisinin. The PfMDR1 N86 plus Y184F isoform moderately reduces piperaquine potency in strains expressing an Asian/African variant of the chloroquine resistance transporter PfCRT. Mutations in both digestive vacuole-resident transporters are thought to differentially regulate ACT drug interactions with host haem, a product of parasite-mediated haemoglobin degradation. Global mapping of these mutations illustrates where the different ACTs could be selectively deployed to optimize treatment based on regional differences in PfMDR1 haplotypes.This work was funded in part by the National Institutes of Health (R01 AI50234, AI124678 and AI109023) and a Burroughs Wellcome Fund Investigator in Pathogenesis of Infectious Diseases award to D.A.F. This research also received funding from the Portuguese Fundacao para a Ciencia e Tecnologia (FCT), cofunded by Programa Operacional Regional do Norte (ON.2-O Novo Norte); from the Quadro de Referencia Estrategico Nacional (QREN) through the Fundo Europeu de Desenvolvimento Regional (FEDER) and from the Projeto Estrategico - LA 26 - 2013-2014 (PEst-C/SAU/LA0026/2013). M.I.V. is the recipient of a postdoctoral fellowship from FCT/Ministerio da Ciencia e Ensino Superior, Portugal-MCES (SFRH/BPD/76614/2011). A.M.L. was supported by an Australian National Health and Medical Research Council (NHMRC) Overseas Biomedical Fellowship (585519). R.E.M. was supported by an NHMRC RD Wright Biomedical Fellowship (1053082). A.C.U. was supported by an Irving scholarship from Columbia University. We thank Dr Andrea Ecker for her help with plasmid design and Pedro Ferreira for his expert help with Fig. 6.info:eu-repo/semantics/publishedVersio

In vitro evaluation of the antimicrobial and antioxidant properties of extracts from whole plant of Alternanthera pungens H.B. & K. and leaves of Combretum sericeum G. Don

Resistance to current antimicrobial agents continues to increase and render difficult the fight against microbial diseases. There is an urgent need to find new disposable and affordable remedies to face this problem. Plants have been used for centuries for health cure and constitute an important source of drugs. In this study, the aqueous, water-ethanol, and water-acetone extracts of Alternanthera pungens H. B. & K. and Combretum sericeum G. Don were evaluated for antimicrobial and antioxidant activities. The antimicrobial activity was evaluated by disc diffusion and microdilution assays. Antioxidant Activity Index (AAI) was determined for antioxidant activity evaluation. The extracts from the leaves of C. sericeum exhibited potent antimicrobial activity. The highest inhibition zone diameters (IZD) were obtained with these extracts. The lowest minimum inhibitory concentration (MIC) (0.625 mg/ml) was recorded against Enterococcus faecalis for all the extracts from this plant and against Lysteria Monocytogenes for the water-acetone extract only. C. Sericeum showed also strong antioxidant activity with AAI comparable to standard antioxidant compounds such as Vitamin C and BHA. A. Pungens showed weak antimicrobial and antioxidant activities, comparatively to C. Sericeum. Phytochemical analyses showed also high total phenolic and total flavonoid contents in C. Sericeum extracts than in A. pungens. The use of these plants in traditional medicine is justified and they constitute a source for further investigations for traditional enhanced drug and active molecules discovery

Les peptides antimicrobiens d’origine microbienne: cas des bactériocines

Les bactéries à Gram positif et à Gram négatif et les archées produisent respectivement des bactériocines et des archéocines. Les bactériocines et les archéocines sont des peptides antimicrobiens. Au fil des ans leur rôle dans la sûreté des produits alimentaires n’a cessé d’être démontré, faisant de ces peptides naturels un centre d’intérêt pour la recherche scientifique. Cette revue tente de faire l’état des connaissances sur les bactériocines produites par les bactéries Gram positif, bactéries Gram négatif et les archées en faisant ressortir leurs organisations génétiques particulières, leurs modes d’action qui diffèrent de celui des antibiotiques et surtout leurs larges spectres d’action. La collecte des données a consisté à consulter les articles scientifiques publiés et les mémoires de thèses sur les différents travaux menés sur les bactériocines et disponible en ligne via les journaux de publication et les sites dédiés aux collectes de thèses en ligne. Ces peptides antimicrobiens pourraient constituer une alternative pour la conservation des denrées alimentaires surtout en milieu rural dans les pays en voie de développement.© 2016 International Formulae Group. All rights reserved.Mots clés: bactériocines, bactéries, archéocines, archées, antimicrobiens, agro alimentaireEnglish Title: Antimicrobial peptides from microbes: case of bacteriocinsEnglish AbstractGram-positive and Gram-negative bacteria and Archaea respectively produce bacteriocins and archeocins. Over the years, their role in the food safety has continued rising because of the report of many works. This review focuses on bacteriocins know up to date by highlighting on their particular genetic organization, their mode of action that differs from antibiotics and especially their broad spectrum of action. Data were collected by consulting online available published scientific articles and thesis on bacteriocins and archeocins. These antimicrobial peptides could provide an alternative for preserving foodstuffs especially in rural areas in developing countries.© 2016 International Formulae Group. All rights reserved.Keywords: Bacteriocins; bacteria; archeocins, archea, antimicrobial activity, agribusines

Economic Valuation of Ecosystem Services in Sahel's Wetlands: Case of Bourgou (Echinochloa stagnina) in the Inner Niger Delta

The Inner Niger Delta (IND) located in Mali provides several ecosystem services to Sahelian people. Among these services, the bourgou fields (Echinochloa stagnina) have a very high value for inhabitants' livelihood and biodiversity. The main objective of this study is to assess the economic value of bourgou ecosystem services in the IND. Specific objectives are to analyze ecosystem services from Echinochloa stagnina and the benefit-cost of its regeneration (plantation) in the IND. The adopted methodology is based on market price and benefit-cost approaches through analysis of collected data from conducted inhabitants' surveys in the circle of Youwarou located in Mali center. The findings show that each Bourgou producer farms on average 7 hectares that provide fish, pasture, livelihoods, and habitats for biodiversity as ecosystem services. The revenue received by bourgou producers with payment for access to pasture for 89,347 cattle is estimated at USD 150,674.78 (47,085,869 FCFA). The benefit of ecosystem services from bourgou is USD/ha 999.22 (312,257 FCFA/ha). To restore bourgou fields, 98.5% of producers are willing to pay USD 192.07 (60,023 FCFA) for it to improve seeds of 1 hectare cultivation. The bourgou culture is a green financing opportunity for income generation, ecosystem services restoration, and biodiversity conservation. Keywords: Bourgou, Biodiversity, Ecosystem services, Income, Inner Niger Delta DOI: 10.7176/JESD/14-17-03 Publication date: November 30th 202