Characterization of strains of Aspergillus flavus and A. parasiticus isolated from groundnut (Arachis hypogea), rice (Oryza sativa) and maize (Zea mays) in Senegal

The contamination of certain food crop with aflatoxin poses a real public health problem for consumers and causes many market losses for exporters. Thus, several research works are oriented in the direction of developing methods to combat aflatoxinogenic fungus. This study aimed at identifying and characterizing strains of Aspergillus flavus and A. parasiticus on groundnut, maize and rice seeds grown or imported into Senegal. Four species (A. niger, A. tamarii, A. flavus and A. parasiticus) were isolated from the seeds with incidences ranging from 0 to 100% depending on the samples and their provenance. Six strains of A. flavus and 3 strains of A. parasiticus have been identified and characterized on CYA and G25N culture media. The characterization focused on the morphological characteristics (color and appearance, mycelial growth) of the colonies on the different culture media, and on some microscopic characteristics such as the density of sporulation (production of conidia) and the appearance of the conidiophore. Strains of A. flavus were more frequent on groundnuts and isolates with the same traits were also identified from rice and maize samples, hence the 3 strains of A. parasiticus were isolated

Enhanced Modelling of Authenticated Key Exchange Security

The security models for Authenticated Key Exchange do not consider leakages on pre–computed ephemeral data before their use in sessions. We investigate the consequences of such leakages and point out damaging consequences. As an illustration, we show the HMQV–C protocol vulnerable to a Bilateral Unknown Key Share (BUKS) and an Unilateral Unknown Key Share (UUKS) Attack, when precomputed ephemeral public keys are leaked. We point out some shades in the seCK model in multi–certification authorities setting. We propose an enhancement of the seCK model, which uses a liberal instantiation of the certification systems model from the ASICS framework, and allows reveal queries on precomputed ephemeral (public and private) keys. We propose a new protocol, termed eFHMQV, which in addition to provide the same efficiency as MQV, is particularly suited for implementations wherein a trusted device is used together with untrusted host machine. In such settings, the non–idle time computational effort of the device safely reduces to one digest computation, one integer multiplication, and one integer addition. The eFHMQV protocol meets our security definition, under the Random Oracle Model and the Gap Diffie–Hellman assumption

N,N′-Dimethyl­ethylenediammonium dioxalatocuprate(II)

The asymmetric unit of the title salt, (C4H14N2)[Cu(C2O4)2], consists of one complex anion and two cationic half-mol­ecules, the other halves being generated by inversion symmetry. The CuII atom in the anion is coordinated by two bidentate oxalate ligands in a distorted square-planar geometry. Inter­molecular hydrogen bonds, involving the NH groups as donors and O atoms as acceptors, are observed, which lead to the formation of a three-dimensional network structure

Biochemical composition and nutritional value of Balanites aegyptiaca (L.) Del fruit pulps from Northern Ferlo in Senegal

Balanites aegyptiaca, a forest species of socio-economic interest for rural people, was chosen to be planted in the frame-work of the Great Green Wall project in Senegal. Although in vastly demand during food scarcity period before crops harvest, the species’ fruit is poorly valued despite its important production. In this study, the fruit pulps were harvested at maturity and the biochemical characteristics were accessed in order to better understand the fruit’s nutritional value. The moisture, sugars, proteins, amino acids, ash, fat, minerals and some vitamins were determined by standard methods of analysis. The results indicated that the fruits are a good alimentary source of sugar, minerals (mainly potassium) and ascorbic acid. The pulp proteins were qualitatively balanced, but were present only in weak quantities. Its caloric value is high due to the high concentration of sugars. Low humidity should allow a fairly good postharvest fruit conservation. The dietary intake of this fruit for local people is very valuable especially in terms of nutrition.Keywords: Balanites aegyptiaca, pulp, biochemical, nutritional valueAfrican Journal of Biotechnology, Vol. 13(2), pp. 336-342, 8 January, 201

Diversity and dynamics of rhizobial populations in acidic soils with aluminum and manganese toxicities in forest zones

Soil acidity in the humid forest zones of Cameroon is one of the major constraints to agricultural productivity. This study was carried out to assess the rhizobial communities of two acidic soils; with aluminum toxicity (Nkoemvone) and manganese toxicity (Nkolbisson) for their potential to improve soil fertility in Cameroon. These two soils were used to inoculate to the host plants cowpea and siratro. At harvest, 120 rhizobacterial isolates were extracted from the nodules of these two hosts and subjected to morphological characterization. Twenty isolates per site were selected and analyzed for their 16S rDNA genetic profile following restrictions with endonucleases of PCR products and electrophoresis. The restriction patterns of the 16S rDNA of the 40 isolates showed 12 different profiles. Eight occurred in both types of soils, where as 4 were specific to the manganese-toxic-acidic soil. While the Al toxicity reduced the nodulation and growth of both plants, the Mn toxicity mostly affect the cowpea. This study ascertained the distribution of rhizobia based on soil characteristics. Further molecular analyses would allow the identification of the isolates recovered as well as their phylogenetical relationships.Int. J. Agril. Res. Innov. & Tech. 6 (2): 12-23, December, 201

Characterization of element and mineral content in Artemisia annua and Camellia sinensis leaves by handheld X-ray fluorescence

Tea infusion is the most frequently worldwide consumed beverage next to water, with about 20 billion cups consumed daily. Artemisia annua leaves contain comparable levels of nutrients and mineral elements (dry matter basis) to many marketed tea (Camellia sinensis) leading us to suspect that this crop could also serve as an alternative source of nutrients for humans. Analyzer moveable X-ray fluorescence is used to evaluate the content of major, minor and toxic elements in A. annua from two different countries compared to six marketed tea in Senegal. To ensure qualified results, certified reference materials were used to perform the calibration. The very low and often negligible levels of inherent elements in the leaves, which are far below recommended toxic levels, establishes A. annua and selected marketed tea as a good reservoir of elements that might favour its use as a potential herbal tonic by humans. The mineral elements are present in different kinds of herbal leaves in various proportions depending on soil composition and the climate in which the plant grows.Keywords: X-ray fluorescence (XRF), Artemisia annua, Camellia sinensis, elements, leaves, medicinal plantAfrican Journal of Biotechnology Vol. 12(26), pp. 4179-418

Evaluation Of Machine Learning Classification Methods For Rice Detection Using Earth Observation Data: Case Of Senegal

Agriculture is considered one of the most vulnerable sectors to climate change. In addition to rainfed agriculture, irrigated crops such as rice have been developed in recent decades along the Senegal River. This new crop requires reliable information and monitoring systems. Remote sensing data have proven to be very useful for mapping and monitoring rice fields. In this study, a rice classification system based on machine learning to recognize and categorize rice is proposed. Physical interpretations of rice with other land cover classes in relation to the spectral signature should identify the optimal periods for mapping rice plots using three machine learning methods including Support Vector Machine (SVM), Random Forest (RF), and Classification and Regression Trees (CART). The database is composed of field data collected by GPS and high spatial resolution (10 to 30 m) satellite data acquired between January and May 2018. The analysis of the spectral signature of different land cover show that the ability to differentiate rice from other classes depends on the level of rice development. The results show the efficiency of the three classification algorithms with overall accuracies and Kappa coefficients for SVM (96.2%, 94.5%), for CART (97.6%, 96.5%) and for RF (98% 97.1%) respectively. Unmixing analysis was made to verify the classification and compare the accuracy of these three algorithms according to their performance

4,6-Dimethyl-2-thioxo-1,2-dihydro­pyrimidin-3-ium chloride–thio­urea (1/1)

In the title compound, C6H9N2S+·Cl−·CH4N2S, the 4,6-di­methyl-2-thioxo-1,2-dihydro­pyrimidin-3-ium cation is proton­ated at one of the pyrimidine N atoms. The cations are bridged by the chloride anions through a pair of N—H⋯Cl hydrogen bonds. The amino groups of each thio­urea adduct inter­act with the chloride anions through a pair of N—H⋯Cl hydrogen bonds and the S atom of another thio­urea adduct through a pair of N—H⋯S hydrogen bonds. These inter­actions result in a layered hydrogen-bonded network propagating parallel to the bc plane. Except for two H atoms, all atoms are on special positions

Evaluation of determinants of the use of health mutuals by the population of the Ziguinchor region in Senegal

Access to health services is a concern around the world. Different strategies were developed, but Africa’s rate remains the lowest. This article aims to contribute to the population's access to healthcare, and to assess the determinants of the use of mutual health insurance by the population of the Ziguinchor region in Senegal.    Methods: The study is transversal and descriptive, carried out from July to August 2018. Through the quota method we defined the number of patients to be interviewed. Thus, by a geographic stratification according to the departments and a second-degree stratification taking into account the staff of the different hospital departments, 392 patients were selected.   Results: 73% at the Regional Hospital Center and 27% at the Regional Peace Hospital. Response rate: 97%, women 60% and men 40%. The enrollment for women (24%) is slightly higher than that for men (21%). Socio-economic factors. The rate of adherence is the highest of for patients with university level, followed by high school; income:  the highest rate for patients with a monthly income between 200,000 and 500,000 FCFA, followed by patients with an income monthly between 100,000 and 200,000 FCFA. Factors linked to the provision of care: the rate of Mutual Health Insurance adherence follows distances from patients' homes. Concerning the relation to satisfaction, education, distance and information are more determining than adherence rate.    Recommendations: 1) State: actions on education and distance; 2) Sensitizing the population on mutual health insurance; 3) Urging healthcare providers to reduce waiting times and respect schedules as well as appointments.&nbsp