Variations in agronomic and grain quality traits of rice grown under irrigated lowland conditions in West Africa

Rice breeding in West Africa has been largely skewed toward yield enhancement and stress tolerance. This has led to the variable grain quality of locally produced rice in the region. This study sought to assess variations in the agronomic and grain quality traits of some rice varieties grown in this region, with a view to identifying sources of high grain yield and quality that could serve as potential donors in their breeding programs. Forty‐five varieties were grown under irrigated conditions in Benin and Senegal with two trials in each country. There were wide variations in agronomic and grain quality traits among the varieties across the trials. Cluster analysis using paddy yield, head rice yield, and chalkiness revealed that 68% of the total variation could be explained by five varietal groupings. One group comprising seven varieties (Afrihikari, BG90‐2, IR64, Sahel 108, WAT311‐WAS‐B‐B‐23‐7‐1, WAT339‐TGR‐5‐2, and WITA 10) had high head rice yield and low chalkiness. Of the varieties in this group, Sahel 108 had the highest paddy yield in three of the four trials. IR64 and Afrihikari had intermediate and low amylose content, respectively, with the rest being high‐amylose varieties. Another group of varieties consisting of B6144F‐MR‐6‐0‐0, C74, IR31851‐96‐2‐3‐2‐1, ITA222, Jaya, Sahel 305, WITA 1, and WITA 2 had high paddy yield but poor head rice yield and chalkiness. The use of materials from these two groups of varieties could accelerate breeding for high yielding rice varieties with better grain quality for local production in West Africa

Positive zeta potential of nanodiamonds

In this paper, the origin of positive zeta potential exhibited by nanodiamond particles is explained. Positive zeta potentials in nano-structured carbons can be explained by the presence of graphitic planes at the surface, which leave oxygen-free Lewis sites and so promotes the suppression of acidic functional groups. Electron Microscopy and Raman Spectroscopy have been used to show that positive zeta potential of nanodiamond is only exhibited in the presence of sp2 carbon at the surface

Coexisting Fermi Liquid and Strange Metal Phenomena in Sr2_2RuO4_4

The strange metal is an enigmatic phase whose properties are irreconcilable with the established Fermi liquid theory of conductors. A fundamental question is whether a strange metal and a Fermi liquid are distinct phases of matter, or whether a material can be intermediate between or in a superposition of the two. We studied the collective density response of the correlated metal Sr$_2$RuO$_4$ by momentum-resolved electron energy-loss spectroscopy (M-EELS). We discovered that a broad continuum of non-propagating charge fluctuations (a characteristic of strange metals) and also a dispersing Fermi liquid-like collective mode at low energies and long wavelengths coexist in the same material at the same temperature. These features exhibit a spectral weight redistribution and velocity renormalization when we cool the material through the quasiparticle coherence temperature. Our results show not only that strange metal and Fermi liquid phenomena can coexist but also that Sr$_2$RuO$_4$ serves as an ideal test case for studying the interaction between the two.Comment: 12 pages, 4 figure

Incidence et regulation naturelle de la chenille mineuse de l’epi de mil, Heliocheilus albipunctella de joannis (Lepidoptera, Noctuidae) a bambey dans le bassin arachidier au Senegal

Au Sénégal, la mineuse de l’épi, Heliocheilus albipunctella (Lepidoptera, Noctuidae) a commencé à causer des dégâts dans les cultures de mil suite à une longue période de sécheresse au début des années 70. Le suivi d’un réseau de 45 parcelles de producteurs à Bambey en 2013, a permis d’évaluer la situation du ravageur : abondance relative (oeuf et larve), parasitisme associé, potentiel de régulation naturelle et pertes de rendement liées aux dégâts. Les résultats ont montré une distribution très hétérogène du ravageur dans la zone avec des moyennes d’infestation des épis en oeufs de 40 % et en larves 76 %. Un taux moyen de parasitisme des oeufs par Trichogrammatoïdea sp estimé à 2 % est noté (n = 2281 oeufs). Le parasitisme larvaire est dominé par des cocons d’endoparasitoïdes de la famille des Ichneumonidae (8,6 %), des larves de Tachinidae (5,2 %) et des morphotypes non encore identifiés (4,6 %). Une faible mortalité larvaire due au Bracon sp. (1,5 %, n = 1567 larves) est observée. Ce faible taux de parasitisme, comparé au potentiel réel de la régulation naturelle observée (59 %, n = 45 parcelles) montre l’importance probable des ennemis naturels dans le contrôle du ravageur. Les pertes en grains sont estimées à 10 %.Mots clés : Heliocheilus albipunctella, mil, régulation écologique, ennemis naturels, dégât

Investigation of Factors Affecting Medication Adherence Among People Living with HIV/AIDS under Non - Governmental Organizations in Senegal

Abstract A ims:This prospective cross-sectional study was carried out to determine factors such as clinical and demographic variab les that may affect medication adherence among people living with HIV/AIDS (PLWHA) receiving treatment at the Institute of health and hygiene of Dakar, but are affiliated to Non-Govern mental Organizations which are HIV/AIDS support group based in Dakar..All consenting subjects from these two support groups were enrolled into study but 305 PLWHA volunteered to participate throughout the three months period of the study. Methods: The study was conducted with the aid of structured interview assisted questionnaires to obtain informat ion on demographic characteristics such as age, sex, occupation, marital status, educational backgrounds, and source of support. Information on availability and side effects of antiretroviral drugs were also obtained. Results:This study indicated that majority of people liv ing with HIV/AIDS interviewed were females (80.3%) while (19.7%) were males. Male respondents show better adherence (91.7%) to ARV med ications than female counterparts (83.7%). Subjects in age the age groups 24-35 years wh ich is the most sexually active groups are mo re vulnerab le (59.1%) when co mpared to other age groups. A large nu mber, (67.2%) were married and there was a significant difference between marital status of PHWHA (P<0.05) and level of adherence to antiretroviral med ications. Descriptive and Chi-square statistical tests were used respectively to evaluate the distribution of respondent's opinion and investigate the level of association between the variables being consideredand respondent'sadherence to antiretroviral med ications. Conclusion: We conclude that there is need to carry out further study in order to fully exp lore the extent to which marital status and other factors can affect medication adherence of people living with HIV/AIDS

Investigation on the risk of brucellosis linked to the production and consumption of milk in rural Cinzana, Mali

Background: The objective of this study was to assess the risk of brucellosis associated with different hygiene practices in the informal dairy production sector in rural Mali and local milk consumption habits. Methods: A cross-sectional study was conducted in 12 villages in the rural commune of Cinzana in Mali, and consisted of two complementary surveys. The first used a participatory approach, based on focus group discussion coupled with open question interviews during general meetings in villages. Its objective was to describe attitudes and practices related to milk production and consumption. The second was a prevalence survey conducted in parallel on humans and dairy herds. In each selected household, serum was collected from people consuming milk or in contact with livestock, after written consent was given. A questionnaire on livestock management practices and milk consumption habits was also administered to households included in the study. Two types of biological samples were collected from dairy cows and goat: raw milk and serum. Screening agglutination Ring test was carried out on milk samples. Rose Bengal test was performed on all human and animal sera. Positive Rose Bengal samples were tested by ELISA for confirmation. Human sera positive to ELISA were re-submitted to a Rose Bengal test by dilution. This confirmatory test allows differentiating between actual infection and exposure to the pathogen. Results: Positive results to the ring test were obtained for 5.9% (2/34) of milk samples from cows and 1.3% (1/75) of milk samples from goat. Only 1.0% (2/204) of sera from cows and 0.7% (3/404) of sera from goat were positive to the Rose Bengal test. The same test gave positive results in 0.9% (2/213) of human sera. All animal positive with Rose Bengal yielded negative results with ELISA, while one serological human case was found. This case was recorded in the village where the 2 positive cow milk samples came from, and where cattle herds are managed individually rather than by the community. The results indicated that 100% and 98.1% of respondents consume milk from cow or goat respectively without prior heating. Handling of abortion material was also common amongst respondents: 72.7% reported it with goats, 6.1% with cows and 11.3% with both species. Summary: This study confirms the presence of human and animal brucellosis in the rural area of Cinzana, Mali. The prevalence found in this study was very low despite widespread risky production and consumption practices. Further investigations on risk factors and preventive practices would be valuable