Wear behaviour of cast aluminium silicon (Al-Si) alloy in dot 4 brake fluid

Abstract : The frictional sliding behaviour of cast Al-Si alloy was investigated with and without DOT 4 hydraulic brake fluid lubrication/environments. Cast Al-Si specimen was produced from wrought alloy and the specimen surface was metallurgically prepared. The as- cast product was characterized with aid of micro-hardness tester, the chemical composition was analysed by X-ray fluorescence (XRF), while X-ray diffraction (XRD) was used to identify phases present, microstructures and surface examinations were done on a high resolution metallurgical Optical Microscope. The properties of the polished and worn sample surfaces were examined by Scanning electron microscope (SEM) equipped with Energy dispersive X- ray (EDS) facilities. A 6mm diameter alumina ball under varying normal loads (3-10 N) was rubbed against the surface of the cast Al-Si coupon specimen. The dry and wet sliding wear behaviour was assessed based on the CoF-sliding time behaviour. From the results, the average CoF values of 0.9064 for dry and 0.2038 for wet contacts were obtained. Comparatively, 1.03E-06 and 4.21E-07 minimum wear intensities; and 467290 and 132170 wear resistances were obtained for dry and wet contacts respectively. Behaviour of cast Al-Si in DOT4 were compared with its performance in DOT3 regarding the hydraulic brake system application

REVIEW OF ACADEMIC LIBRARY INFORMATION AND HUMAN RESOURCES: EVIDENCE FROM OSUN STATE UNIVERSITY, NIGERIA

Generally, the library is referred to as the knowledge hub of higher education institutions, saddled with the responsibility of supporting the teaching, research, and community engagement function in the university. These libraries are conceived to enable them genuinely handle the information needs of library clientele. In the wake of the COVID-19 pandemic, the human traffic to the physical library shrinks which brings more responsibility to the library personnel who works from home to make the library resources available to users at their various locations. The emerging responsibility motivated this study which investigated the appraisal of academic library information resources and human resources in Sola Akinrinade Central Library of Osun State University in Nigeria. A structured questionnaire was used for data collection. A sample of three hundred and forty-five respondents were selected using a simple random sampling technique. Two hundred and seventy-five copies were returned. Findings from the study revealed that available information resources and human resources in the academic library do not meet the accredited academic library standards. Similarly, the academic library is not sufficiently and adequately funded which has grossly affected the provision of the available information and human resources. The researchers recommend that recruitment of professional librarians and other library support staff; provision of quantity and quality information resources, and integration of academic library in the plan of higher institutions among other measures would improve the relevance of library and human resources in higher institutions of learning

Renegotiation of public private partnership road contracts: Issues and outcomes

The renegotiation of road projects has been an important issue that has generated concerns in PPP procurement over the last decade. This has had serious policy implications for public procurement policy across countries because of its implications for the achievement of the objectives defined at the inception of PPP road contracts. This paper assesses the renegotiation of Public-Private Partnership (PPP) infrastructure projects in order to identify the issues involved in renegotiation and its outcomes. Data were collected through a literature review of selected studies on PPP infrastructure projects on a sectoral basis with particular emphasis on Latin America, Portugal and Spain. It was revealed that a high proportion of PPP contracts in the transport sector are renegotiated: Indeed, in the transport sector, more PPP road projects are renegotiated than other forms of transport projects. The main factors surrounding the renegotiation of road contracts are: lack of an adequate contract design, frequent opportunistic behaviour on the part of both public and private partners during the implementation of PPP road projects, changes in the conditions affecting revenue and costs beyond the reasonable assumptions accounted for in the original contract, corruption, and political and economic instability, all of which in most instances reduce the chance of the public partner achieving its objective of value for money (VfM). The paper concludes with a discussion of the need to develop a framework for integrating considerations of value for money into the renegotiation process of PPP road contracts

Groundwater Quality Assessment in a University Sub-Urban Community in Delta State, Nigeria: Part A-Physicochemical Analysis

This study provides detailed scientific information on the physicochemical  properties of drinking water from groundwater in a Nigerian university sub-urban community. Water samples from boreholes (BHs) and handdrawn wells (HDWs) in the community were collected and analyzed for their  biological and physicochemical parameters, and the metals from July 2016 to January 2017 for wet and dry seasons. Results obtained, showed that the physicochemical factors complied with the World Health Organization  (WHO) guidelines, except for pH being lower in some locations. In the wet and dry seasons, pH varied from 4.4 to 6.2 and from 4.8 to 6.7  respectively. While the mean value for wet season was 5.7, dry season was 5.9; to give a seasonal mean difference of 0.2.Cd and Pb, in both wells, for many locations, were slightly higher than the prescribed limits. The slight elevated concentrations of Pb and Cd could be attributed to oil exploration activities in the study area. The study recommends the provision of improved drinking water in the community.Keywords: Groundwater, quality monitoring, contamination, Niger-Delt

Comparative Characteristics of Integrin αDβ2 Binding to Native Fibrinogen and Fibrinogen Modified by DHA Oxidation During Inflammation

2-ω-carboxyethylpyrrole (CEP) is a product of docosahexaenoic acid (DHA) oxidation, which forms covalent adducts with different proteins. CEP-modified proteins can interact with macrophage receptor, integrin αDβ2. This study aims to compare αDβ2 binding to its physiological ligand, fibrinogen, and CEP-modified fibrinogen, which is formed during inflammation. We hypothesize that modification of fibrinogen changes its ligand-binding properties to integrin αDβ2 which can affect macrophage migration and retention. Recombinant αD I-domain and αDβ2-transfected HEK293 cells were used for the experiments. Using biolayer interferometry, we found that the affinity of αD I-domain binding to fibrinogen-CEP was higher than fibrinogen and inhibited by the anti-CEP antibody. In agreement, αDβ2-transfected cells demonstrated stronger adhesion to fibrinogen-CEP and this adhesion was significantly inhibited by polyglutamic acid that mimics CEP-mediated binding. These findings suggest that αDβ2\u27s interaction with DHA-modified extracellular matrix (ECM) proteins significantly increases macrophage adhesion and may serve for macrophage retention during chronic inflammation

The experience of African American parents with the special education system : a review of literature

textThis study is a review of literature on the experiences of African American parents of children with disabilities in the special education system. The reviewed works span between 1990 and 2014, and the purpose of the review is to understand (a) the experiences of African American parents of children with disabilities with the special education process, (b) the factors impacting these parents participation in their children’s education, (c) their experiences with special education professionals, and (d) their perspectives on the factors that hinders or facilitate their relationship with special education professionals. Thirteen studies met the inclusion criteria of being published in peer-reviewed journals or dissertations and investigating the experiences of African American parents of children who receive special education services. The findings suggest that parents' participation in special education processes and parent-professional relationships are influenced by factors such as communication issues, cultural difference, support from the system, knowledge of special education law and procedures. I conclude this study by proposing recommendations for improving the experiences of African American parents in special education process.Special Educatio

The Impact of Military Rule on Nigeria’s Nation Building, 1966-1979

For a significant part of its post independence existence, Nigeria was under military rule. The military rule that firstly brought new hopes however did little to salvage the precarious situations that collapsed the first republic. It has to be stated that the army was already contaminated by one of the viruses that brought down the civilian government---regionalism. Therefore it could be said that the ‘doctor’ himself was ill, and who could cure him but himself. Consequently, there was a ‘self surgery’ which resulted in the thirty month civil war. This paper assesses the first phase of military rule in Nigeria (1966-1979) in relation to the country’s nation building. The paper examines problems and prospects of nation building during this phase of military rule. The paper however concludes that the military rule, 1966-79 contributed both positively and negatively to the building a viable and united Nigerian nationhoo

A Theological Analysis of Confessional-Centric Curriculum of Christian Religious Education: Towards an Inclusive Religious Pluralistic Centered Curriculum for Nigeria Colleges of Education

Desire to live in peace and unity despite the multi ethnic and multi religious composition of Nigeria, remain ideals that are constant in the nation’s Constitution. However, accruable benefits of a culturally and religiously pluralistic society have continued to elude Nigeria due to incessant religious violence arising from the mutual suspicion of Christians and Muslims in the country. Nevertheless, the nation’s National Policy on Education proposes the education sector as one of the platforms to inculcate a sense of unity and religious tolerance in the country. The policy considers the nation’s learning centers and religious courses offered in such institutions as media to attain the goals of peaceful co-existence and unity of all citizens. Unfortunately, this goal has remained unrealized. It is from this background that this dissertation conducts a theological analysis of the curriculum of Christian Religious Studies operative in Nigeria Colleges of Education and finds it defective by default for the purpose of facilitating religious harmony in the country. For one, the curriculum is mostly catechetical in content, and transmits a confessional orientation of religious studies across board from the training of CRS teachers, to their engagement in teaching at primary and secondary school levels. The project deploys Jacque Dupuis’ ‘inclusive religious pluralism’ in drafting a Christian religious studies curriculum for Nigeria Colleges of Education. The submission is made on the assumption that a robust community of religiously pluralistic society operates on respect for each other’s’ religious views, and avoidance of attempt at relegating adherents of other religions and their religious views to an inferior status

When it no longer matters whom you love: the politics of love and identity in Nigerian migrant fiction

experiences of love, intimacy and connected identity politics in the diaspora. However, there is a paucity of scholarly engagements with Nigerian migrant writers’ representation of the complexities that attend the formation and reconfiguration of migrant characters’ identity and love relationships outside the motherland. This study, therefore, examines the intersection of love, place and identity in three purposively selected texts – Segun Afolabi’s Goodbye Lucille, Chimamanda Adichie’s Americanah and Unoma Azuah’s Edible Bones. The three novels are closely read and analysed using the Postcolonial theory’s conceptions of Othering and  unhomeliness, in order to foreground the impact of the ‘condition of the diaspora’ on migrant characters’ relationships and identity negotiations. The study reveals that all three novels feature characters that struggle to align their multiple identities and at the same time maintain meaningful love relationships outside the motherland. There is also the representation of same-sex marriages, green marriages, dysfunctional inter-national, inter-racial and transnational relationships, and the negative effects of distance on love relationships. Time and chance then determine the politics of love and identity in diasporic spaces. Nigerian migrant writers represent the pervasively unpleasant experiences of migrant characters belied in the construction of love with identity politics as coordinate relationships in the Nigerian diaspora, through a rhetoric pain and suffering, in order to underscore the unpleasant second side that there is to the migration narrative of bliss and fulfilment. Thus, they destabilise the hegemonic discourses around West-ward emigration as the panacea to African subjects’ experience of postcolonial disillusionment, in an effort to write back, write right and write committedly

Development Agenda in Nigeria: The Imperatives of New Approach to National Security

The changing perception of threats to national security has called for a broad understanding of the nature and drivers of security threats to the nation as well as raised the need to rejig our approach to addressing the threats taking into account that modern day security is no longer only the concern of defense but steering the society towards achieving sustainable development. The perceived deep-seated animosity and disillusionment in Nigeria are giving rising to virtual epidemic of threats to national security raising the need for Nigerian policy-makers to pay attention on the softer side of threats to national security as well as adopting new approach to stemming the rising waves of security challenges across the land different from the usual conventional measures. The paper examines the changing nature of security threats to the nation and the imperatives for new designs, programs and strategies to deal with these threats in order to rekindle public confidence. Keywords: Development Agenda, Expanding Threats and National Securit