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Abdulsalam M.,University of Witwatersrand | Abdulsalam M.,Umaru Musa YarAdua University | Joubert D.P.,University of Witwatersrand
Physica Status Solidi (B) Basic Research | Year: 2016

We present first principles calculations of the electronic and optical properties of bulk and monolayer structures for four transition metal chalcogenides, MX2 (M=Zr and Hf; X=S, Se), using a post density functional many-body perturbation GW approximation in conjunction with the Bethe-Selpeter approximation (GW-BSE). Optical absorption spectra predict the presence of a strongly bound exciton that lies below the direct band gap in two bulk (HfS2 and ZrSe2) and in all the monolayer structures. The binding energy of the excitons are predicted to lie between 0.11 and 0.96eV. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

Saulawa L.A.,Katsina University | Yaradua A.I.,Umaru Musa YarAdua University
Pakistan Journal of Nutrition | Year: 2014

Effect of different processing methods on chemical profile of Baobab (Adansonia digitata) seed meal was investigated. Raw Baobab seeds were collected for the study. Five different processing methods (Boiling, toasting, soaking, soak and boiling and sprouting) were used. All the processed seeds with the exception of toasted seeds were oven dried before milling for chemical analysis. Result of the study shows that raw baobab seed contains 28.85% CP with a reasonable amount of mineral and energy, it also contain some anti-nutritional factors. Processing significantly reduced crude protein, mineral and anti nutrition factors content but improved energy content. Boiling gave the least percentage reduction of crude protein and highest percentage reduction of anti nutritional factor. Boiling processing is recommended for baobab seed. © Asian Network for Scientific Information, 2014. Source

Ibrahim M.A.,Ahmadu Bello University | Mohammed A.,Ahmadu Bello University | Isah M.B.,Umaru Musa YarAdua University | Aliyu A.B.,Ahmadu Bello University
Journal of Ethnopharmacology | Year: 2014

Ethnopharmacological relevance African trypanosomiasis is one of the neglected tropical diseases caused by different species of trypanosomes that affect both human and livestock with devastating consequences in the continent. Most of the affected populations commonly use traditional medicinal plants for the treatment of the disease. Consequently, this prompted ethnopharmacological research activities on the anti-trypanosomal activity of a number of these African medicinal plants in order to validate their ethnomedicinal use. Furthermore, such studies could lead to the identification of chemical leads for the development of newer anti-trypanosomal agents from those plants. This review aims to provide updated information on the ethnopharmacological evidence of African medicinal plants with anti-trypanosomal activity. Methods Literature was collected via electronic search (PubMed, Sciencedirect, Medline and Google Scholar) from published articles that report on the in vitro or in vivo anti-trypanosomal activity of plants that were collected from different parts of Africa. Results African medicinal plants investigated for in vitro and in vivo anti-trypanosomal activity from January 1993 to October 2013 are systematically compiled and all the in vivo studies are critically discussed. A total of 264 plant species belonging to 79 families were investigated for anti-trypanosomal activity. However, only 48 bioactive anti-trypanosomal compounds were successfully isolated in pure forms. Furthermore, some of the plants were investigated for possible ameliorative effects on the trypanosome-induced pathological changes out of which 18 plants were reported to be effective while a few others were not. In spite of interesting preclinical ethnopharmacological evidence for anti-trypanosomal activity, not a single African medicinal plant was investigated in a clinical study. Conclusion Several African medicinal plants have demonstrated promising anti-trypanosomal effects but the studies on the anti-trypanosomal potentials of these plants are not taken beyond proof of concept stage. It is hoped that the article would stimulate future clinical studies because of the paucity of knowledge in this area. © 2014 Elsevier Ireland Ltd. Source

Idris I.M.,University Putra Malaysia | Idris I.M.,Umaru Musa YarAdua University | Abu Bakar M.R.,University Putra Malaysia
Physica A: Statistical Mechanics and its Applications | Year: 2016

The effect of non-immunogenic tumor microenvironmental factors on tumor growth dynamics modeled by correlated additive and multiplicative colored noises is investigated. Using the Novikov theorem, Fox approach and Ansatz of Hanggi, an approximate Fokker-Planck equation for the system is obtained and analytic expression for the steady state distribution Pst(x) is derived. Based on the numerical results, we find that fluctuations of microenvironmental factors within the tumor site with parameter θ have a diffusive effect on the tumor growth dynamics, and the tumor response to the microenvironmental factors with parameter α inhibits growth at weak correlation time τ. Moreover, at increasing correlation time τ the inhibitive effect of tumor response α is suppressed and instead a systematic growth promotion is noticed. The result also reveals that the strength of the correlation time τ has a strong influence on the growth effects exerted by the non-immunogenic component of tumor microenvironment on tumor growth. © 2016 Elsevier B.V. All rights reserved. Source

Abdulsalam M.,University of Witwatersrand | Abdulsalam M.,Umaru Musa YarAdua University | Joubert D.P.,University of Witwatersrand
Physica Status Solidi (B) Basic Research | Year: 2016

Abstractauthoren Abstractauthoren The electronic and optical properties of semiconducting TiS3, HfS3, HfSe3, ZrS3, and ZrSe3 with structure P21/m have been investigated for the first time at the G0W0 and BSE level of approximations, respectively. The structures were relaxed using PBE with the inclusion of van der Waal's correction terms to account for long-range dispersion forces, which is a necessary ingredient in predicting an accurate description of structural properties of layered systems. In order to predict reasonable estimates of the electronic properties, MBJ, HSE06, and G0W0 were used to calculate the fundamental band gaps of the structures and the Bethe-Salpeter equation (BSE) was solved to obtain an accurate description of the optical properties of the compounds. It is found that the compounds have G0W0 band gaps between 0.58 to 2.17eV. Their optical absorption spectra revealed that they start to absorb light in the range of 0.9-1.63eV making them potential materials for third-generation solar photovoltaic applications and possible photo-catalysis applications. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

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