Real Space Observations of Magnesium Hydride Formation and Decomposition

The mechanisms of magnesium hydride formation and thermal decomposition are directly examined using in-situ imaging.Comment: 3 pages, 4 figure

Maladies et plantes vasculaires du Karité (Vitellaria paradoxa Gaertn) au Bénin

La présente étude vise à évaluer les maladies et les plantes vasculaires du karité (Vitellaria paradoxa C. F. Gaertn) dans les savanes Soudanienne (SS) et Nord guinéenne (SNG) du Bénin. Pour ce faire, quarante sites au total ont été prospectés au cours du mois de juillet 2018. Sur chaque site, l’incidence et la sévérité des symptômes de maladies, la densité et la distribution des plantes vasculaires ont été étudiées. Des échantillons de feuilles malades, des plantes vasculaires du karité ont été prélevés pour lʼidentification au laboratoire. Lasiodiplodia theobromae, Colletotrichum gloeosporioides, Pestalotiopsis sp, Xanthomonas sp ont été les agents pathogènes identifiés. Les valeurs d’incidence étaient élevées dans la SS (59,6% L. theobromae, et de 42,2% Xanthomonas sp) et dans la SNG (67,5% Pestalotiopsis sp et de 55% L. theobromae). Les valeurs de sévérité étaient élevées dans la SS (39% L. theobromae et de 30,6% Xanthomonas sp) et dans la SNG (54,7% Pestalotiopsis sp et 43% L. theobromae). Les données collectées sur la densité des plantes vasculaires ont montré une Orchidiaceae holo-épiphyte (Calyptrochilum christyanum), une Moraceae hémi-épiphyte (Ficus thonningii), une Renonculaceae (Alafia barteri) et deux Loranthaceae (Tapinanthus dodoneifolius, Tapinanthus globiferus). T. dodoneifolius et T. globiferus sont plus répandus avec des taux d’infestation moyens respectifs de 68,67% et de 66,58% et des densités moyennes par plant respectives de 5,64 touffes et de 2,52 touffes. Ainsi, les efforts d’amélioration de la production de karité doivent prendre en compte les stratégies de lutte contre ces agents pathogènes et plantes vasculaires.   The present study aims to assess diseases and vascular plants of the shea-butter tree (Vitellaria paradoxa C. F. Gaertn) in Sudan Savanna (SS) and Northern Guinea Savanna (NGS) of Benin. Thus, forty (40) sites in total were surveyed in July 2018. On each site, incidence and severity of the disease symptoms, and density and distribution of vascular plants of the shea-butter tree were studied. Samples of diseased leaves and vascular plants of the sheabutter tree were collected for laboratory identification. The pathogens Lasiodiplodia theobromae, Colletotrichum gloeosporioides, Pestalotiopsis sp) and Xanthomonas sp were identified. The incidence values were high in SS (59.6% L. theobromae and 42.2% Xanthomonas sp) and in NGS (67.5% Pestalotiopsis sp and 55% L. theobromae). The severity values were high in SS (39% L. theobromae and 30.6% Xanthomonas sp) and in NGS (54.7% Pestalotiopsis sp and 43% L. theobromae). Data collected on the density of vascular plants of the shea-butter tree showed one holo-epiphytic Orchidiaceae (Calyptrochilum christyanum), one Moraceae (Ficus thonningii), one Renonculaceae (Alafia barteri) and two Loranthaceae (Tapinanthus dodoneifolius, Tapinanthus globiferus). T. dodoneifolius and T. globiferus were more widespread with respectively infestation rate of 68.67% and 66.58%, and respectively average densities per shea plant of 5.64 tufts and 2.52 tufts. Thus, efforts to improve shea-butter production must take into account strategies for disease pathogens and vacular plants control in the sheabutter parklands in Benin

A comparison of Mini-FLOTAC and McMaster techniques in detecting gastrointestinal parasites in West Africa Dwarf sheep and goats and crossbreed rabbits

McMaster (McM) method is one of the most widely used techniques for the assessment of faecal parasites shedding in veterinary practices because of its simplicity. However, due to its light sensitivity, recently, the Mini-FLOTAC (MF) has been introduced as a possible alternative for faecal worm egg counts. This study aims to compare the diagnosis performance of MF to McM technique. Faecal samples from 40 animals randomly selected in sheep, goats and rabbits' farms were collected and examined individually using MF and McM techniques. A statistical difference (p 0.05). MF showed better diagnostic performance in term of the prevalence (MF: 32.5-100% vs McM: 7.5-70%) and the precision values (MF: 85.52-90.44% vs McM: 49.52-63.07%). This study demonstrated that MF appears to be the more reliable alternative technique for veterinary practices

Synergistic ultraviolet and visible light photo-activation enables intensified low-temperature methanol synthesis over copper/zinc oxide/alumina

Although photoexcitation has been employed to unlock the low-temperature equilibrium regimes of thermal catalysis, mechanism underlining potential interplay between electron excitations and surface chemical processes remains elusive. Here, we report an associative zinc oxide band-gap excitation and copper plasmonic excitation that can cooperatively promote methanol-production at the copper-zinc oxide interfacial perimeter of copper/zinc oxide/alumina (CZA) catalyst. Conversely, selective excitation of individual components only leads to the promotion of carbon monoxide production. Accompanied by the variation in surface copper oxidation state and local electronic structure of zinc, electrons originating from the zinc oxide excitation and copper plasmonic excitation serve to activate surface adsorbates, catalysing key elementary processes (namely formate conversion and hydrogen molecule activation), thus providing one explanation for the observed photothermal activity. These observations give valuable insights into the key elementary processes occurring on the surface of the CZA catalyst under light-heat dual activation

La diversité génétique des bananiers plantains cultivés dans la zone Ouest de la Région des Plateaux au Togo

Le bananier représente l’une des cultures les plus importantes dans le monde. Au Togo, la culture de bananiers plantains se fait surtout dans la Région des Plateaux à l’Ouest dans de petites exploitations agricoles ; ce qui a entrainé une faible productivité. Cependant, les variétés de bananiers plantains cultivées ne sont pas bien connues. Un inventaire a été entrepris dans le but de dénombrer les variétés de bananiers plantains cultivés grâce à des paramètres agromorphologiques et aussi de montrer l’intérêt que suscite la valorisation de la culture de cette plante. Au terme de cette étude, cinq (5) variétés de bananiers plantains ont été recensées. La variété ‘Apim’ est la plus productive suivie de la variété ‘Abladzo’. Contrairement aux autres, la variété ‘Taévé’ produit 2 régimes par pied au lieu d’un régime. Le cycle végétatif des bananiers plantains varie de 11 à 15 mois sauf pour la variété ‘Apim’ qui est de 18 mois. Des études de propagation rapide doivent être envisagées pour la sélection des variétés hautement performantes et la production massive du plantain pour les populations locales.© 2013 International Formulae Group. All rights reserved.Mots clés : Togo, bananier plantain, diversité génétique

Intramuscular Artesunate for Severe Malaria in African Children: A Multicenter Randomized Controlled Trial.

BACKGROUND: Current artesunate (ARS) regimens for severe malaria are complex. Once daily intramuscular (i.m.) injection for 3 d would be simpler and more appropriate for remote health facilities than the current WHO-recommended regimen of five intravenous (i.v.) or i.m. injections over 4 d. We compared both a three-dose i.m. and a three-dose i.v. parenteral ARS regimen with the standard five-dose regimen using a non-inferiority design (with non-inferiority margins of 10%). METHODS AND FINDINGS: This randomized controlled trial included children (0.5-10 y) with severe malaria at seven sites in five African countries to assess whether the efficacy of simplified three-dose regimens is non-inferior to a five-dose regimen. We randomly allocated 1,047 children to receive a total dose of 12 mg/kg ARS as either a control regimen of five i.m. injections of 2.4 mg/kg (at 0, 12, 24, 48, and 72 h) (n = 348) or three injections of 4 mg/kg (at 0, 24, and 48 h) either i.m. (n = 348) or i.v. (n = 351), both of which were the intervention arms. The primary endpoint was the proportion of children with ≥ 99% reduction in parasitemia at 24 h from admission values, measured by microscopists who were blinded to the group allocations. Primary analysis was performed on the per-protocol population, which was 96% of the intention-to-treat population. Secondary analyses included an analysis of host and parasite genotypes as risks for prolongation of parasite clearance kinetics, measured every 6 h, and a Kaplan-Meier analysis to compare parasite clearance kinetics between treatment groups. A post hoc analysis was performed for delayed anemia, defined as hemoglobin ≤ 7 g/dl 7 d or more after admission. The per-protocol population was 1,002 children (five-dose i.m.: n = 331; three-dose i.m.: n = 338; three-dose i.v.: n = 333); 139 participants were lost to follow-up. In the three-dose i.m. arm, 265/338 (78%) children had a ≥ 99% reduction in parasitemia at 24 h compared to 263/331 (79%) receiving the five-dose i.m. regimen, showing non-inferiority of the simplified three-dose regimen to the conventional five-dose regimen (95% CI -7, 5; p = 0.02). In the three-dose i.v. arm, 246/333 (74%) children had ≥ 99% reduction in parasitemia at 24 h; hence, non-inferiority of this regimen to the five-dose control regimen was not shown (95% CI -12, 1; p = 0.24). Delayed parasite clearance was associated with the N86YPfmdr1 genotype. In a post hoc analysis, 192/885 (22%) children developed delayed anemia, an adverse event associated with increased leukocyte counts. There was no observed difference in delayed anemia between treatment arms. A potential limitation of the study is its open-label design, although the primary outcome measures were assessed in a blinded manner. CONCLUSIONS: A simplified three-dose i.m. regimen for severe malaria in African children is non-inferior to the more complex WHO-recommended regimen. Parenteral ARS is associated with a risk of delayed anemia in African children. TRIAL REGISTRATION: Pan African Clinical Trials Registry PACTR201102000277177

Monitoring fever treatment behaviour and equitable access to effective medicines in the context of initiatives to improve ACT access: baseline results and implications for programming in six African countries

BACKGROUND: Access to artemisinin-based combination therapy (ACT) remains limited in high malaria-burden countries, and there are concerns that the poorest people are particularly disadvantaged. This paper presents new evidence on household treatment-seeking behaviour in six African countries. These data provide a baseline for monitoring interventions to increase ACT coverage, such as the Affordable Medicines Facility for malaria (AMFm). METHODS: Nationally representative household surveys were conducted in Benin, the Democratic Republic of Congo (DRC), Madagascar, Nigeria, Uganda and Zambia between 2008 and 2010. Caregivers responded to questions about management of recent fevers in children under five. Treatment indicators were tabulated across countries, and differences in case management provided by the public versus private sector were examined using chi-square tests. Logistic regression was used to test for association between socioeconomic status and 1) malaria blood testing, and 2) ACT treatment. RESULTS: Fever treatment with an ACT is low in Benin (10%), the DRC (5%), Madagascar (3%) and Nigeria (5%), but higher in Uganda (21%) and Zambia (21%). The wealthiest children are significantly more likely to receive ACT compared to the poorest children in Benin (OR = 2.68, 95% CI = 1.12-6.42); the DRC (OR = 2.18, 95% CI = 1.12-4.24); Madagascar (OR = 5.37, 95% CI = 1.58-18.24); and Nigeria (OR = 6.59, 95% CI = 2.73-15.89). Most caregivers seek treatment outside of the home, and private sector outlets are commonly the sole external source of treatment (except in Zambia). However, children treated in the public sector are significantly more likely to receive ACT treatment than those treated in the private sector (except in Madagascar). Nonetheless, levels of testing and ACT treatment in the public sector are low. Few caregivers name the national first-line drug as most effective for treating malaria in Madagascar (2%), the DRC (2%), Nigeria (4%) and Benin (10%). Awareness is higher in Zambia (49%) and Uganda (33%). CONCLUSIONS: Levels of effective fever treatment are low and inequitable in many contexts. The private sector is frequently accessed however case management practices are relatively poor in comparison with the public sector. Supporting interventions to inform caregiver demand for ACT and to improve provider behaviour in both the public and private sectors are needed to achieve maximum gains in the context of improved access to effective treatment