Screening of UV-irradiated and S-2-aminoethyl-Lcysteine resistant mutants of Bacillus megaterium for improved lysine accumulation

The screening of UV irradiated and aminoethyl-l-cysteine resistant (AECR) mutants of Bacillus megaterium strains for improved lysine accumulation was conducted. The mutants, MR-10 and MR-25 derived form irradiated cultures of B. megaterium SP 76, and MS-3 and MS-5 derived form B.megaterium SP 86 produced higher lysine levels than the parent strains. In contrast, however, lysine accumulation by MV-2 and MV-18 mutants of B. megaterium SP 14, was of low yield. In aminoethyl-lcysteineresistant mutants, R-14 and R-76, derived from B. megaterium SP 14 and B. megaterium SP 76 respectively, lysine accumulation was enhanced

Effect of vitamins and bivalent metals on lysine yield in Bacillus megaterium

The effects of vitamins and bivalent metals on lysine accumulation in Bacillus strains were investigated. Biotin enhanced lysine production in all the Bacillus strains, while folic acid and riboflavin stimulated lysine yields in Bacillus megaterium SP 86 only. All bivalent metals stimulated lysineaccumulation in B. megaterium SP 86 and B. megaterium SP 14, while Co2+ and Zn2+ improved lysine levels in all the strains

United Nations Security Council Resolutions in Africa : the conundrum of state and human insecurity in Libya.

Thesis (M.A.)-University of KwaZulu-Natal, Pietermaritzburg, 2013.Both interventionist and anti-interventionist scholars have advanced the view that the 2011 Libyan conflict probes the need to establish an international organisation to settle disputes between nations with a view to maintaining international peace and security. Ironically, 67 years after the founding of the United Nations, post-colonial African states remain deeply troubled and affected by conflicts that are often exacerbated by United Nations Security Council (UNSC) Resolutions. The 2011 Libyan conflict was not a war for democracy; rather, it represented and demonstrated clearly the asymmetrical relations between Africa and Europe. This study therefore, is anchored on the thesis that the Western Countries—especially Britain and France—within the UNSC ignore the values that are embodied in the Treaty of Westphalia which established state sovereignty. Some Permanent five (P5) members of the UN were typically insensitive to Libya’s sovereignty and to the creed of democracy and this inevitably undermined the national security of the state in favour of the ‘Responsibility to Protect’ clause. The outsourcing of the UNSC’s mission, among other things, in Libya to ensure ‘international peace and security’ to the North Atlantic Treaty Organisation (NATO) was a critical reason for the loss of human lives and values in the 2011 Libyan pogrom. The introduction of a no-fly zone over Libya and the use of Responsibility to Protect (R2P) contained in UNSC Resolution 1973 clearly stoked the conflict in Libya in order to further the political and pecuniary interests of some of the P5 members. The involvement of NATO and the attendant bombing campaign in Libya served to undermine the militarily weak continent of Africa in its effort to broker peace under the umbrella of the African Union (AU). In order to secure these political and economic interests, the NATO jet bombers declared war against a sovereign UN member state and openly participated in the eventual overthrow and death of the Libyan leader, Muammar Gaddafi. In essence, this study underscores that the use of Responsibility to Protect in Libya was orchestrated at the highest level of international politics to justify external interference and ultimately, to secure regime change in Libya. The net effect of the outcome of the 2011 Libyan conflict is the post-war imperial control of Libya’s natural resources facilitated by the National Transition Committee established by these imperial forces. The extent of the damage caused by the UN-backed NATO intervention in Libya is also the result of the collective failure of the African Union to assert itself in the Libyan situation

The nexus between the United Nations Security Council reform and peacebuilding in Africa.

Doctor of Philosophy in Conflict Resolution and Peace Studies. University of KwaZulu-Natal, Pietermaritzburg 2015.The nexus between the United Nations Security Council reform and peacebuilding in Africa is underpinned by the recognition that the Security Council is the supreme organ of the UN; and its reform saga is a conundrum to Africa’s peacebuilding and security praxis. In assortment of ways, this study observes that the Council is created in atmospheres of major realpolitik and has unrepentantly deprived the African continent for 70 seventy years, of meaningful contribution. As the harbinger for global peace and security, the Council lacks geographic representativity and is bias towards Africa’s real peace which has fanned insecurity paradigm in the continent. The study recognises that African inclusion into the permanent chambers of the Council will entrench Africa’s role for global security and armistice. The African exclusion matrix is a clearly-thought-out strategy of the imperial forces in the Permanent Five (P5) which has processed economic deprivation - making the continent perpetually dependent on imperial powers, and politically marginalised - keeping the same at the periphery of the pot of global politics since 1945. In the current global community, peace in Africa is a call of worldwide significance due largely to the observation that, conflicts in Africa accounts for over calculated 70% of world conflicts. Conflicts destroy the pillars for peace and terminate Africa’s interest to succeed in containing insecurity regime in the region and elsewhere. Conversely, lack of Council’s restructuring has reinforced insecurity regime, and exacerbated the dependency syndrome in the thinking-faculty of African leaders. Actually, some African nations are with necessary capabilities to become permanent members of the Security Council, but US and allies are against African inclusion on the altar of maintaining the status quo and retaining the exclusive core for a realist outlook that, the League of Nations and United Nations are children of World Wars I and II respectively. However, the study among other things learnt that dependency on external actors and marginalisation of Africa may continue until Africa speaks one word with one voice. That is, to demand permanent seat with veto or simultaneously withdraws membership from the UN through the AU’s common front. The study, essentially, extended the frontiers of existing knowledge and expanded the horizons of facts on the Security Council reform, and peacebuilding in Africa

Studies on lysine production by Bacillus megaterium

A Lysine-producing strain recovered from soil was found to produce large amount of the amino acid. The bacterium identified as Bacillus megaterium SP 14 accumulated a lysine yield of 3.56 mg/ml in a broth culture in 96 h. Fermentation experiments show that 8.0% (w/v) glucose and 4.0% (w/v) ammonium chloride used as sources of carbon and nitrogen, respectively, in a medium/fermenter volume ratio of 25.0%, influenced accumulation of the amino acid. Amino acids other than the aspartate family at 0.01% (w/v) stimulated growth and improved lysine yield. Addition of 0.01 unit/ml penicillin to the fermentation medium, immediately after inoculation, stimulated growth and appreciably enhanced lysine accumulation.African Journal of Biotechnology Vol. 4 (7), pp. 633-638, 200

Investigations into the influence of temperature on the optical properties of NiO thin films

Nanocrystalline thin films of nickel oxide (NiO) have been deposited on glass substrates in polyvinylpyrrolidon (PVP) matrix solution by chemical bath deposition technique. The films have been annealed at 373 K–573 K and changes in their optical properties have been studied. Investigation reveals that the optical properties of the films have been irregularly influenced by heat treatment. They show varied transmittance for different annealing temperatures making them useful for applications in optoelectronic devices. The structural property of the films has been obtained by means of X-ray diffraction (XRD), while the elemental composition has been deduced from Rutherford back scattering spectroscopy (RBS). XRD analyses of the film annealed at 375 K show that the films are crystallized and have rhombohedral structure. The crystallite size of the film has been determined and found to be 89.90 nm. The films band gaps range from 2.30 eV – 2.95 eV, which are lower than that of their solid materials. This however makes them useful for antireflection coatings and other applications

Lysine Production of Microbacterium lacticum by Submerged Fermentation Using Various Hydrocarbon, Sugar and Nitrogen Sources

Abstract Bacterial isolation from oil-contaminated and uncontaminated soil was screened for hydrocarbon utilizer which was also capable of producing lysine. Microbial production of lysine by Microbacterium lacticum was investigated in submerged fermentations using various concentrations of hydrocarbon, sugar sources and nitrogen. Of the nine sugar and five nitrogen sources tested, glucose/ammonium sulphate proved optimum for lysine production. Effect of varying concentration of carbon and nitrogen sources on lysine accumulation showed that glucose (4%) ammonium sulphate (1%) respectively increased lysine production. A gram positive rod bacterium identified as Microbacterium lacticum was identified. Optimizing the cultural conditions of Microbacterium lacticum in submerged medium gave a methionine yield of 2.99 mg/ml lysine in the broth culture after 96 h

Study of the Effects of Thermal Annealing on the Optical Band Gap of Nanocrystalline CoO Thin Films Prepared by Chemical Bath Deposition.

Nanocrystalline films of cobalt oxide have been prepared on glass slides by chemical bath deposition process. For deposition of CoO thin films, cobaltous chloride [CoCl2.6H2O] was used as cationic and ammonia [NH3] as anionic precursor in aqueous medium. In this process NaOH was used as complexing agent. X-ray diffraction, scanning electron microscopic [SEM] analysis have been used to study the films’ crystal structures, optical and solid state properties. We hereby present the effects of thermal annealing on the optical band gap of CoO thin films. The optical transition in the films is direct one. For the as- deposited film, the band gap is 2.1eV. This later decreased to 2.08eV, so that increased thermal annealing reduces the optical band gap of CoO. However,the energy gap cannot be said to be dependent on the annealing temperatures. These films could be used as  photovoltaic cells, sensors light emitting diodes and also in biomedical imaging. Key Words: Nanocrystalline CoO, Chemical Bath Deposition, Band Gap and                               Thermal Annealing

Effects of p-type-metal-doping (Ba, Cs, and Y) of the compact-TiO2 electron transporting layer on the photovoltaic properties of n-i-p perovskite solar cells

Tailoring of charge transport properties of the electron transport layer (ETL) in solution-processible solar cells is continuously addressed not only for the performance enhancements in perovskite solar cells but also in various other applications in nanotechnology. In this work, three p-type dopants: barium, cesium (Cs), and yttrium (Y) with varying crystal radii and charges are doped in the titanium dioxide (TiO2) material so as to modify the electrical and optical properties of the ETL. The pure and doped TiO2 films were prepared by spin-coating a sol–gel precursor and their effects on the crystal structure, morphology, optical, electrical and photovoltaic properties of the perovskite solar cells were studied and reported. Among them, Y-doped TiO2 with similar crystal radii as that of the host titanium atom showed an enhanced photo-conversion efficiency mainly contributed by enhanced open circuit voltage and fill factor. The power conversion efficiency (PCE) for the perovskite absorber layer on Cs- and Y-doped TiO2 show the maximum PCE of 2.81 and 4.50% respectively. These are encouraging results for optimizing the yttrium doping level and fabrication conditions to further push the performance indicators of PSCs

Women and democratic leadership in Africa: An appraisal

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