Proceedings of the Nigerian Academy of Science (Journal)
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Africa And Cancer: Preparing For The Next Epidemic
Full text linkIt is my singular honour to deliver this guest lecture to a distinguished audience under the auspices of the Nigerian Academy of Science (NAS). Essentially tagged first quarter lecture in 2012, it can be likened to a state of the Union Address to the nation through NAS. I am proud to be a fellow of the Nigerian Academy of Science (NAS), the foremost scientific organization in Nigeria with the aim of promoting the growth, acquisition, and dissemination of scientific knowledge and to facilitate its use in solving of major problems of national interest. I am also aware that our President is likely, Dr. Goodluck Jonathan, GCFR, to assume office as the next Chair of the African Union and have taken the liberty as President of the African Organisation for Research and Training in Cancer (AORTIC) to deliver a sermon on Cancer to Africa on this occasion. I thank the President, Prof Oye Ibidapo-Obe FAS,and the entire fellows of the Academy for the honour bestowed on me. I also thank my Chairman, Chief Wole Olanipekun SAN, who graciously accepted to chair this occasion at such notice despite his busy schedule.Africa is the world’s second largest and second most populous continent, after Asia. Africa with a landmass of about 30.2 million km2 (11.7 million sq mi) including adjacent islands, covers 6% of the Earth’s total surface area and 20.4% of the total land area.With 1.0 billion people in 65 territories (including 54 recognized states), it accounts for about 14.72% of the world’s human population. The continent is surrounded by the Mediterranean to the north, both the Suez Canal and the Red Sea along the Sinai Peninsula to the northeast, the Indian Ocean to the southeast, and the Atlantic Ocean to the west.Africa straddles the equator and encompasses numerous climate areas; it is the only continent to stretch from the northern temperate to southern temperate zone.Africa’s population is relatively young but has rapidly increased over the last 40 years. In some African states, half or more of the population is under 25 years of age. The total number of people in Africa grew from 221 million in 1950 to 1 billion in 2009
Modelling Transition From Normal To Epileptic Eeg Signals: A Neuron-Astrocyte Mass Action Approach
Full text linkEpileptic seizures occur intermittently as a result of complex dynamical interactions among many regions of the brain. The sudden and apparently unpredictable nature of refractory seizures is one of the most disabling aspects of the disease. Therefore, there is need for interdisciplinary research efforts directed at better understanding of the mechanisms involved in the emergence of epileptic seizures. Our research objective in this field is the use of applied methods from deterministic and nondeterministic dynamical systems modeling to study epilepsy. Dynamical systems refer to systems whose state variables evolve in time. By the assumption of deterministic system,the physiological system (the brain) can be treated as low dimensional without any random components. Nondeterministic assumption on the other hand allows randomness in some input components. We developed at the macroscopic level physiologically based mathematical models of parts of the brain believed to be eliciting the abnormal signals observed during Generalized Absence Epilepsy (GAE) and Temporal Lobe Epilepsy (TLE). In developing our models, we considered the activities of nerve cells, the surrounding astrocyte cells and the dynamics of extracellular neurotransmitters and conducted parameter sensitivity studies on our models. The models were then validated using Electroencephalogram (EEG) data of epileptic patients.The important conclusion from our findings is that the transition from normal to epileptic brain activity is critically dependent on small variations in few system parameters and/or the balance between a small number of system parameters, be it neural or astrocytes activity dependent
Precision Die Design by The Die Expansion Method
Full text linkA new method for the design of precision dies used in cold forging, extrusion and drawing processes is presented. It is based on die expansion. It attempts to provide a clear-cut theoretical basis for the selection of critical die dimensions for this group of precision dies when the tolerance on product diameter (or thickness) is specified. It also presents a procedure for selecting the minimum-production-cost die from a set of design alternatives. The results show that as external die diameter increases, die expansion decreases while die strength increases. Also, as the degree of die compounding increases, die expansion decreases and die strength increases. Comparison of theoretical and experimental results shows good agreement especially at full die cavity filling stage. Die selection from a set of multi-layer dies is based on the die that has minimum Design Effectiveness Index (DEI) which gives the minimum-production-cost die. It is hoped that the design method, apart from providing solutions to simple design problems, can be applied as a first approximation to the solution of more complex problems, based on a clear-cut theory rather than the usual rule-of-thumb method. Thereafter, more sophisticated computer-based methods may be applied for refinement
Space Technology As Binoculars For Life On Earth In The 21st Century
Full text linkMan’s romance with Space remains one of the wonders of all ages. In material terms, it has inspired quantum leaps in the technology of flight and transportation; on the metaphysical or spiritual plane our imagery of heaven and hell are both conjured and inspired by space and the myriad balls of fire and dark holes that define and decorate its spacescape. Biblical account of the divine act of creation merely confirms its pre-eminence in man’s thoughts when it says:"And God said, Let there be light in the firmament of the heaven to divide the day from the night: and let them be for signs, and for seasons, and for days, and years;And let them be for lights in the firmament of the heaven to give light upon the earth: and it was so.And God made two great lights; the greater light to rule the day; and the lesser light to rule the night: he made the stars also.And God set them in the firmament of the heaven to give light upon the earth,And to rule over the day and over the night, and to divide the light from the darkness: and God saw that it was good".(Genesis 1:14-18)For it was against the forboding vastness of space and the warmth, and mystery of the beckoning stars that man discovered both his identity and consciousness. Homo Sapien’s early confrontation with nature must, most probably, have been so traumatic and intimidating as to make him seek refuge in the caves to contemplate his frailty and helplessness and in the process fashion out a survival kit. Such a survival kit evolved over just a few millions of years to transform him, not only into a master of his planet, but also in recent times, into a space adventurer. His survival kit was built around two central themes viz:-(a) the need to know himself and everything about anything around him .(b) the use of what he knows to improve and manage his present condition of life on the one hand and predict and plan for the future on the other.After all, physical and scientific or metaphysical explorations and discoveries are predicated in the need to know, whereas innovation and technology merely reflect the ends and use to which man has put what he knows
An Interventional Strategy for addressing The Social Development and Reproductive Health Needs of The Youth in Nigeria; Lessons Learnt
Full text linkThe youth constitute a critical age group especially in a populous nation like Nigeria. Therefore, a lot more needs to be done to address the needs (social development and reproductive health) of the youth. The Nigerian Academy of Science set up a project to address the needs of youth by working with the youth and various stakeholders, including two state governments, to identify and develop evidence-based policy to respond to the needs. The needs assessment involved data collection from the youth and other stakeholders and the collective review of the findings. Consequently, strategic plans were developed for each state. Diverse strategies were employed which promoted partnership among the stakeholders and led to ownership of the policy documents (strategic plans) developed.
Amplitude Spectrum and Edge Detection Attributes for Channels Discrimination and Geometry in Otumara Field, Niger Delta, Nigeria.
Full text linkGeological interpretation of seismic data traditionally fulfill two main objectives: solving geometry of structures with possible hydrocarbon accumulations and correlation of recorded seismic amplitudes with lithology, with the latter based on factors largely depending on interpreters’ previous experiences. Upon the transformation of seismic data into frequency domain using the Fast Fourier Transform, the phase spectra indicate lateral geologic discontinuities while the amplitude spectra delineates temporal bed thickness variability, thus making the spectral decomposition technique an effective tool in discriminating geobody within a 3D seismic data such as channel fills and associated lithofacies. From its inception, spectral decomposition has been used in highlighting channels. In many tertiary basins such as the Niger Delta, there is a direct correlation between strong amplitude, greater porosity and the presence of hydrocarbons. We have employed such frequency attribute complimented with similarity, illustrating real possibilities in identifying stratigraphic features of interest