Development and Evaluation of Mild Steel Permanent Mould for Al-Alloys Pulley Production

The development and evaluation of a mild steel permanent mould were conducted with considerations based on materials availability, cost efficiency, and national economic development. The design, material selection, and fabrication strategy were all carefully chosen to meet these objectives. Geometric modelling of the mould design was carried out using Pro/Engineer® software, generating various views and parameters of the mould with and without components. Mild steel was chosen for mould production due to its strength, rigidity, availability, high melting temperature, surface finish, and machinability. Fabrication of the mould utilized basic machine tools such as a lathe machine and drilling machine. To evaluate the performance of the developed mould, an aluminium alloy pulley was produced using the mould and aluminium scraps. Microstructural analysis and hardness tests were performed on mould samples before and after casting. The results indicate that the heated mould sample, after casting, exhibits a fine-induced dendritic structure comprised of smaller grains, whereas the microstructure of the unheated mould displayed larger grain sizes. The maximum hardness number recorded was 204 HV for the mould sample after casting, indicating the ability of the mould material to withstand fatigue stresses and wear generated during casting

PRESERVING FEDERALISM, LOCAL AUTONOMY IN A RESOURCE DEPENDENT RURAL STATE: A CASE OF NIGERIA

Abstract The Paper explores the practical implications of the new political economy of federalism, Tiebout hypothesis and the subsidiarity principle all of which couched around the modern market system of federal governance. Focusing on Nigeria's experimentation, the paper casts a dissenting voice to the emergent converging proposition of the new political economy of federalism by arguing that federal governance is not merely a matter of market efficiency because the distinctive features of plural societies often require that both principles of good economics and federal governance be subordinated to political considerations. After exploring the practical implications of the Nigerian market preserving model of federalism in the light of its "three-player ethnic game," the inference is that, there is organic relationship between the logic of the market and state, and the contradiction between "competitive federalism" and "cooperative federalism" that undermines the centralizing tendencies and enhances federalism's perdition, and therefore predisposes the state to adopt both defective model of development and federal governance. Against the prevailing orthodoxy, the paper avers the need to move from a "market preserving federalism" that encourages "bargaining and compromise" at the cost of social equity to an institutional dimension and makes a case for yet another experimentation with the social market economy model of the East Asian and the Nordic nations which lays greater emphasis on social equity and participative aspects of delivery as well as encouraging of freedom of choices, political, social, economic and cultural freedom within the rule of law. Finally, as an alternative to the prevailing nominal modern market system of federal governance in Nigeria, the paper concluded by noting that the concept and practice of market preserving federalism had to be deconstructed to reflect the extension of the concept of market into politics and original idea behind federalism as a model of political organization

Trial of Labour after Caesarean Section in a Secondary Health Facility in Abakaliki, Nigeria

Background: The mode of delivery of a parturient is influenced by previous caesarean section (CS) scar. Objective: The objective of the study is to evaluate the pregnancy outcomes of a parturient with one previous caesarean delivery that was managed in Mile Four hospital, Abakaliki, Nigeria. Materials and Methods: A 5‑year retrospective study of women with one previous CS who delivered in Mile Four hospital between January 2011 and December 2015 was done. IBM SPSS version 20 was used for data analysis, and data were represented using frequency tables, charts, and Chi‑square. The level of significance was set at an alpha level of 0.05. Results: Three hundred and twenty‑two (322) women with one previous CS were selected for a trial of labor after A C/S (TOLAC). More than half of the women (53.1%) had successful TOLAC while 46.9% had a repeat CS. Of the 53.1% of women who had a successful TOLAC, One hundred and forty-one patients had spontaneous vertex delivery. Seventeen women (9.9%) on the TOLAC arm had a ruptured uterus, while seven patients (4.6%) failed the TOLAC group had uterine dehiscence. Haemorrhage was the most common maternal complication. Severe asphyxia and perinatal death were present in 5.9% and 5.3% of neonates on TOLAC arm, respectively. Conclusion: Trial of labour after a CS can result in an excellent outcome in a well‑selected patient. The success rate of 53.1% in our study is encouraging. However, adequate intrapartum monitoring is recommended to reduce maternal and fetal complications

Development of hardfaced crusher jaws using ferro-alloy hardfacing inserts and low carbon steel substrate

Procedures for producing hardfaced jaws using ferro-alloy hardfacing inserts and low carbon steel substrate have been established. This research was prompted by the need to provide an economical substitute to the high manganese austenitic steel that has dominated the mining and minerals industries since its invention by Sir Robert Hadfield in 1882. In this research, ferro-alloy hardfacing inserts of composition 72.80 %Fe. 12.32 %Mn, 7.38 %Cr were produced by sand casting. The inserts were welded to low carbon steel substrate by manual metal arc-welding to form the hardfaced jaws. Welding was carried out intermittently using E6013 gauge 10 oerlikon electrode and a current of 100 A. The fixed and movable jaws lost 0.3 and 0.1 kg, respectively, after crushing 400 kg of granite in the jaw crusher. Hardness values and wear volumes of the hardfacing insert and workhardened Hadfield steel were 653 HV, 0.0069 cm3 and 517 HV, 0.017 cm3, respectively. Cost of producing the hardfaced jaws was five times cheaper than the estimated cost of producing Hadfield steel jaws. Consequently, the hardfaced jaws can economically substitute the Hadfield steel jaws in jaw crushers

Oral drug delivery: Gastrointestinal tract adaptations, barriers and strategies for delivery enhancement - a review

The mouth is a vital route of drug administration with over 84 % of all medicines reportedly administered through it. The gastrointestinal system is equally imbued with a lot of adaptive features that make the oral route even more conducive for systemic drug delivery. The usefulness of the oral route is, however challenged by the existence of numerous absorption barriers which limit the effective absorption and delivery of drugs to their target sites in the body systems. Understanding these adaptive attributes, systemic barriers and available strategies for overcoming such barriers will not only be helpful in drug development and design but also useful to the formulation scientists desirous of optimizing drug delivery. The objective of this work was to review the gastrointestinal route of drug administration with respect to some biochemical and physio-anatomic features that impede or enhance drug absorption and to highlight current strategies that have been deployed to achieve optimum per oral drug delivery. The current review reveals the emerging roles of nanocarriers in oral drug delivery. Polymeric nanocarriers enhance the solubility, targeting and safety profiles of many important pharmacological agents. Novel systems that offer protection against gastro enzymes and as such, promote oral administration of biologicals are being widely investigated. Mechanical, magnetic, and acoustic energy – induced membrane perturbation are other delivery options receiving research attentions. It may be concluded that, with the avalanche of research efforts in the area, the oral route will maintain its prominence among other routes of drug administration. &nbsp

Information and Communication Technology (ICT) as a Panacea for Overcoming the Challenges of COVID-19 Pandemic: A Study of Academic Staff Performance in Tertiary Institutions in Enugu State, Nigeria

The sudden outbreak of COVID-19 and its consequential lockdown led to the closure of tertiary institutions across the globe. The closure had severe implications by stopping academic staff from going to work and performing their jobs. However, to navigate the implication of the closure of tertiary institutions on teaching and learning, ICT and its accessories were leveraged to enable the academic staff to work remotely. Therefore, this study aimed to investigate the adoption of ICT in cushioning the effect of the pandemic on the performance of academic staff in tertiary institutions, using Enugu State as a study base. Technological determinism theory was employed in the analysis. The methodology used is a cross-sectional survey that leveraged qualitative and quantitative approaches. Data were collected using both primary and secondary sources. The population of the study is 8,034, with a sample size of 381. However, 312 questionnaires were used after retrieval from the respondents; sorting, cleaning, and scoring. We coded and analyzed the data using descriptive statistics from the IBM SPSS version 28.0, leveraging tables, percentages, and content analysis. The study adopted a Chi-Square (X 2 ) test of hypotheses. Findings revealed that tertiary institutions leveraged ICT to cushion the effects of COVID-19 on academic staff performance, work-life balance, training and development, and safety during the pandemic. The study recommends full digitization of tertiary institutions, staff training and re-training, adequate funding, constant power supply, and development of indigenous capacity in ICT

Awareness and Attitude of Senior Secondary School Students towards HIV/AIDS Risk Factors and Preventive Measures in Ebonyi State, Nigeria

The study determined the level of awareness and attitude towards HIV/AIDS risk factors for enhanced preventive measures among senior secondary school students in Ebonyi State. The study adopted a convergent parallel mixed-method design. The population of the study comprised of all the 6,912 Senior Secondary 2 (SS2) students in Ebonyi North Education Zone. The sample for the study comprised 378 senior secondary school (SS2) students. The instruments for data collection were a questionnaire developed by the researchers and a Focus Group Discussion Guide. Both instruments namely the questionnaire and the focus group discussion guide were face validated by experts from the University of Nigeria, Nsukka. Quantitative data analysis was done using mean and standard deviation and t-test statistics. Qualitative analysis with respect to the Focus Group Discussion was done using thematic analysis method. Findings of the study showed among other things that senior secondary school students are aware of HIV/AIDS risk factors and do have a positive attitude toward such HIV/AIDS risk as well as their preventive measures. The findings of the study further revealed that there was no significant difference in the mean responses of male and female students on attitude and preventive measures towards HIV/AIDS risk factors in the study area. Similarly, there was no significant difference in the mean responses of urban and rural senior secondary school students on awareness of HIV/AIDS risk factors and attitude towards the risks factors in the study area. However, there was a significant difference in the mean responses of male and female students on awareness of HIV/AIDS risk factors with the female students having a higher mean than their male counterparts. There was also a significant difference in the mean responses of urban and rural students on awareness of HIV/AIDS preventive measures with the urban students having a higher mean than those in the rural area

Development of ferro-alloy hardfacing for high abrasion and low impact wear applications

Extension of service lives of critical machine components subjected to wear is possible through application of hardfacing alloys. In this work, two hardfacing alloys were produced based on the mass ratios of 2: 1: 1 and 7: 1.5: 1.5 for Fe: Mn: Cr by sand and open permanent mold casting processes, respectively. XRD analysis of both samples showed the prominent presence of (Mn, Cr)23C6, (Fe, Mn, Cr)7C3, Cr3C2, Fe3C2 and Fe4C carbides. Hӓgg carbide was prevalent in the SEM microstructural analysis of the sand cast sample, while cementite dominated the permanent mold cast sample. The average hardness values, impact energies absorbed and wear volumes of the samples produced with their respective charge mass ratios are 567 HV, 30 J and 0.131 cm3 for 2: 1: 1 ratio and 592 HV, 29.5 J and 0.085 cm3 for the 7: 1.5: 1.5 ratio. For service life applications as jaws, rolls, mantles, and concaves in crushers, the latter was recommended for manual metal arc welding to low carbon steel substrate because of its higher hardness, lower wear volume and cheaper alloy cost