395 research outputs found
Equal Channel Angular Extrusion Characteristics on Mechanical Behavior of Aluminum Alloy
Materials strengthened by conventional methods such as strain hardening, solute additions, precipitation and grain size refinement are often adopted in industrial processes.
But there is limitation to the amount of deformation that these conventional methods can impact to a material. This study focused on the review of major mechanical properties
of aluminum alloys in the presence of an ultrafine grain size into polycrystalline materials by subjecting the metal to an intense plastic straining through simple shear without
any corresponding change in the cross-sectional dimensions of the sample. The effect of the heavy strain rate on the microstructure of aluminum alloys was in refinement of the
coarse grains into ultrafine grain size by introducing a high density of dislocations and subsequently re-arranging the dislocations to form an array of grain boundaries. Hence, this investigation is aimed at gathering contributions on the influence of equal channel
angular extrusion toward improving the mechanical properties of the aluminum alloys through intense plastic strain
Return for postnatal check: current situation in a Nigerian tertiary health institution
Objective: This study aims to determine the current prevalence of postnatal clinic attendance among parturients who delivered in a Nigerian teaching hospital.Methods: A two year review of obstetric record of women who delivered in the hospital from July 2010 to June 2012 and were scheduled to attend Postnatal Clinic was done. The list was cross checked with the postnatal clinic record to know patients who kept their appointment by attending the clinic. A frequency table was generated and data were analyzed.Results: In the first year, out of 1267 women 264 (20.8%) returned for postnatal clinic. During the second year, 1651 women delivered in the hospital while 759 (46.0%) came back for postnatal clinic. Aggregate prevalence of postnatal clinic attendance among the parturients was 35.1%.Conclusion: Most parturients who had hospital delivery do not return for postnatal clinic in our environment.Keywords: delivery, postnatal, clinic, attendanceTrop J Obstet Gynaecol, 30 (1), April 201
Public Participation in Local Government Planning and Development: Evidence from Lagos State, Nigeria
When members of the public are given the opportunity to participate in local governance, the benefits are immeasurable. Unfortunately, the structure and mechanisms for promoting public participation, especially in the context of a developing country, is underexplored. In this paper, we examine the structure and mechanisms for public participation in two randomly selected communities within Lagos Mainland Area of Lagos State, Nigeria. Specifically, we measure public participation in terms of the quality of interaction among the members of the community, as well as the interaction between the community and the Local Government Council. Selected Heads of Traditional Councils in these communities were interviewed using semi-structured interviews. The findings show that “face-toface” relationship is a dominant strategy for promoting public participation within t he Makoko/Iwaya communities. Consequently, we established that the potential of ICT in the promoting of public participation is far from being explored in these communities. The corresponding policy implications are discussed and recommendations to enhancethe use of ICT for promoting public participation are suggested
Diagnosis and clinical management of teeth with vertical root fractures: a literature review
The diagnosis of vertical root fracture (VRF) is at times complicated for lack of specific signs, symptoms and/or radiographic features. It constitutes an important threat to the tooth’s prognosis during and after root canal therapy and may result in root or tooth extraction. Early detection and management of VRF remain a vexing issue that has caused needless stress for both the dentist and the patient. This paper presents an overview of the prevalence and multifactorial aetiology of VRF, the clinical and radiographic features of this disorder, the importance of correct diagnosis and treatment options available for both anterior and posterior teeth. An exhaustive review of literature was done using Medline to bring out various etiologic factors, clinical presentations, radiographic features and treatment alternatives available for VRF. There are, however, many specific clinical and radiological signs which when present, can alert clinicians to the existence of a fracture. Even though VRF are commoner in endodontically treated teeth, its occurrence in non-restored teeth has been described. Clinical signs and symptoms vary according to the position of the fracture, tooth type, duration after fracture, periodontal condition of the tooth and architecture of the bone adjacent to the fracture. The radiographic appearance of teeth with VRF is variable depending on the angulation of X-ray beam in relation to the plane of the fracture, the time after fracture and the degree of separation of the root fragments. It is important to recognize the sometimes subtle findings in VRF so that patient can be properly informed about the prognosis and the potential for successful treatment in affected tooth\teeth
Effect of protein deficient diets on the growth and carcass protein ash ratio of African catfish Clarias gariepinus (Burchell 1822)
As the prices of fish feed ingredients continue to soar due to economic and environmental challenges, many fish farmers now produce practical fish diets deficient in protein, to minimize costs and maximize profits. This study evaluated the effects of such diets on the growth performance and carcass quality of African catfish, Clarias gariepinus. Five dietary treatments used contained 25%, 30%, 35%, 40% and 45% protein, respectively. Fish were fed for 70 days and the results showed high and improved growth performance in relation to the increasing dietary protein levels. Carcass protein, ash and minerals correlated positively with increasing dietary protein levels while the lipids had inverse relationship. Generally, fish fed diets of 25-35% protein had lower performance than those fed the control diets of 40 or 45% protein reported as the requirements for the fish. However, and in all cases, there were no differences in the performance of fish fed 40 or 45% protein diet, indicating no significant additional benefits from feeding the fish with 45% protein diet. The results also suggested the protein requirement of the fish to be above 35% and about 40%. The carcass protein-ash ratio was observed to be constant and ranged between 4.08 and 4.82. © JASE
Evaluation of Energy Use in Public Housing in Lagos, Nigeria: Prospects for Renewable Energy Sources
Even though domestic energy can be from either renewable or non-renewable sources, the former is preferred because of its role in reducing both the operational energy intensity and carbon footprint. Given the positive role renewable energy plays in the energy mix, this paper examined the pattern of operational energy use with particular reference to the renewable and non-renewable energy content in medium and high density public residential buildings in Lagos, Nigeria. A survey research method was adopted for primary data collection while data analysis was by descriptive statistics. The study found that renewable energy use in the residential units is very low. In contrast, there was high dependence of the occupants on non-renewable direct fuel combustion through the use of fossil fuel-driven privately-owned electricity generators for electricity supply as a result of the inadequate supply from the national grid. In addition to the relatively high operational energy intensity observed in the studied buildings, the findings have implications for the safety, health and wellbeing of the building occupants as well as for carbon emissions from the buildings and for overall environmental sustainability. Recommendations to increase renewable energy use in new buildings and as retrofits in existing buildings were made. Article History: Received Oct 18, 2015; Received in revised form January 14, 2016; Accepted January 30, 2016; Available online How to Cite This Article: Ezema, I.C., Olotuah, A.O., and Fagbenle, O.I, S. (2016) Evaluation of Energy Use in Public Housing in Lagos, Nigeria: Prospects for Renewable Energy Sources. Int. Journal of Renewable Energy Development, 5(1),15-24. http://dx.doi.org/10.14710/ijred.5.1.15-2
Characterization of potential ethylene-producing rhizosphere bacteria of Striga-infested maize and sorghum
Three rhizosphere bacteria, Pseudomonas sp., Enterobacter sakazakii and Klebsiella oxytoca, were analyzed for genetic variation. DNA fingerprint patterns of the three bacteria were markedly different when amplified with different primers. In total, 68 bands were produced by the three primers, 62 of which where variable. The number of polymorphic RAPD loci per isolate ranged from one to 13. Cluster analysis indicated that E. sakazakii and K. oxytoca are the most closely related of the three.
(African Journal of Biotechnology: 2002 1(2): 67-69
The Role of State and Professional Bodies in Developing Code for Structural Concrete – Learning from other Nations
In order to arrest the rampant structural failures of buildings, there have been call for the development and adoption of structural design codes that will capture all relevant environmental issues that are peculiar to Nigeria. This paper presents the results of analysis of data collected from the public domain (libraries and internet sources) on Nations with acceptable structural design codes in concrete and allied materials. Some of the findings are that: (i) Code or Standard does not necessarily need to be a legal document or backed by the state to enjoy wider acceptance or be recognized, (ii) it is possible for people in the same professions to form professional association and regulate the operation of the profession by setting standard of practice which can be recognized, not only by people, but also acceptable to the State and (iii) whether a standard developed as a legal document or recommendations of professional association, openness and consideration for the inputs for all are necessary. This is to ensure that the operation of the standard will not run contrary to the public good, or in violation of the common law, or infringe the rights of a subject/citizen. Keywords — Building failures, Codes, Concrete, Legal document, Professional bodies, Structures
Phytochemical screening and in-vitro antibacterial activity of leaf extracts of Justicia secunda Vahl on selected clinical pathogens
The phytochemical constituents and antibacterial activity of leaf extracts of Justicia secunda against five selected clinical pathogens were investigated. Leaves of Justicia secunda were obtained and authenticated, and subjected to drying at room temperature for thirty days. The dried leaves were blended into powder for solvent extraction. Aqueous, ethanol and methanol, extracts of the leaves were prepared and concentrated using a rotary evaporator. The phytochemical analysis was carried out using standard methods while the antibacterial activity of the extracts against the clinical isolates was determined using the agar well diffusion method. Saponins, tannins, flavonoids, cardiac glycosides, terpenoids, steroids, anthraquinones and alkaloids were all present in the methanol, ethanol and aqueous extracts, while cardiac glycosides and alkaloids were absent in the aqueous extract. All the extracts had antibacterial activity against the test bacteria at 150 mg/mL, with the exception of the aqueous and methanol extracts that had no activity against E. coli. The MIC of the aqueous extract for both B. cereus and L. monocytogenes was 37.5 mg/mL, 150 mg/mL for S. aureus, 18.75 mg/mL for P. aeruginosa, with no activity against E. coli. The methanol extract of had a minimum inhibitory concentration (MIC) of 18.75 mg/mL on all the tested bacteria, with the exception of E. coli with no activity, while the MIC of the ethanol extract on P. aeruginosa was 75 mg/mL, and 18.75 mg/mL for the other bacteria. J. secunda could be promising in the future design of antibacterial drugs due to its antibacterial properties as observed in this study.
DOI: http://dx.doi.org/10.5281/zenodo.398513
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