Cost Management Practice of Construction Firms and Its Influencing Factors: Lessons from Southwestern Nigeria

The growing need at maintaining steady cost projection of construction projects has been an issue of serious concern to both the clients and the construction practitioners on sites. Also, cost deviation from initial cost plan and cost budget has been prevalent on construction sites and no concerted efforts have been made at addressing this phenomenon. This study therefore examined the factors that are considered to be affecting the cost management practice of construction firms in the southwestern Nigeria and also proffered possible ways of ameliorating the factors. Using survey approach, one hundred copies each of structured questionnaires were distributed to clients, contractors and consultants on construction sites in the study area while 72, 77 and 78 copies were duly filled and returned by the respondents respectively. Relative Importance Index (RII) technique was used for the analysis. The results revealed that poor leadership and in appropriate management, inefficient deployment of resources, excessive wastage of materials on sites, complex payment mechanisms, theft of materials on sites and variation during construction works are the prevailing factors affecting construction cost management practice in the study area. It was concluded that extra focus should be placed on the identified factors with a view to reducing cost of construction, enhancing construction performance and building confidence within the construction industry in the study area

Interaction Between Hot Carrier Aging and PBTI Degradation in nMOSFETs: Characterization, Modelling and Lifetime Prediction

Modelling of the interaction between Hot Carrier Aging (HCA) and Positive Bias Temperature Instability (PBTI) has been considered as one of the main challenges in nanoscale CMOS circuit design. Previous works were mainly based on separate HCA and PBTI instead of Interacted HCA-PBTI Degradation (IHPD). The key advance of this work is to develop a methodology that enables accurate modelling of IHPD through understanding the charging/discharging and generation kinetics of different types of defects during the interaction between HCA and PBTI. It is found that degradation during alternating HCA and PBTI stress cannot be modelled by independent HCI/PBTI. Different stress sequence, i.e. HCA-PBTI-HCA and PBTI-HCA-PBTI, lead to completely different degradation kinetics. Based on the Cyclic Anti-neutralization Model (CAM), for the first time, IHPD has been accurately modelled for both short and long channel devices. Complex degradation mechanisms and kinetics can be well explained by our model. Our results show that device lifetime can be underestimated by one decade without considering interaction

The Role of Irish Potato Farmers of the Women-in-Agriculture and Youth Empowerment (WAYE) Programme in Plateau State, Nigeria

Youth Empowerment (WAYE) programme in Plateau State, Nigeria. A multi-stage sampling method was employed to select 256 respondents. Primary data were collected through the use of questionnaires and were subjected to both descriptive and inferential statistics. The mean farming experience was 10 and 16 years for participating and non-participating farmers while mean farm size for participating farmers and non- participating farmers was 1.4 and 0.5 ha. The result of the findings reveals that, (55%) and (47%) of the participating farmers and non-participating farmers had secondary school education, which constituted the largest number of educational qualification attained in the study area. Factors influencing the level of participation of Irish potato farmers in WAYE programme in Plateau State are, marital status (3.72, P<0.01), sex (2.25, P<0.05), years of Irish potatoes production (9.85, P<0.01), household size (10.92, P< 0.01), awareness of WAYE programme (4.93, P< 0.01), a unit increase in these factors will subsequently influence the level of participation of Irish potato farmers in WAYE programme. The mean crops output of WAYE programme participants (537,807.1kg) was significantly higher than non-participants (165,571.43kg). The difference in the mean crops output levels was largely attributed to participation in WAYE programme. The calculated Z-test value (14.74) for crops output and income (22.93) was significant at 1% probability level. It was therefore recommended that WAYE programme be extended to other farming communities in Plateau State, so as to accelerate the poverty alleviation among women farmers in the State. &nbsp

Production and characterization of activated carbon from leather waste, sawdust, and lignite

Powdered activated carbon (PAC) was prepared from leather buffing waste, sawdust and lignite by carbonization at temperatures between 500 – 800oC followed by steam activation. Experimental results reveal a general decrease in yield of carbon residue with increase in temperature of carbonization. Samples of lignite recorded the highest yield (49.80 – 67.70%) followed by leather buffing dust (30.70 – 39.70%) and sawdust (25.10 – 37.20%). Activated carbon from these precursors, were also evaluated for percentage ash, fixed carbon, pH and bulk density. Adsorption studies carried out with methylene blue indicate that low temperature carbonization of precursors such as leather buffing waste favour production of carbon with better adsorption efficiency while high temperature carbonization produced carbon with better efficiency from sawdust and lignite. Activated carbon from sawdust and leather buffing waste show result which compare favourably with the reference carbon used. These carbons are recommended for use in the adsorption of dyes or decolourization of organic compounds and other substances in aqueous solutions.Key words: Activated carbon, carbonization, Steam activation, Adsorption efficiency, Leather buffing wast

RETRAINING NEEDS OF MOTOR VEHICLE MECHANIC TEACHERS AND INSTRUCTORS ON AUTOMATIC TRANSMISSION SYSTEM FOR TEACHING IN TECHNICAL COLLEGES IN BAUCHI STATE

The study was designed to identify the areas of retraining needed by the teachers and instructors of Motor Vehicle Mechanics (MVM) trade in the technical colleges in Bauchi State, Northeastern Nigeria. The objective of the research was to identify the pedagogical and practical skills at technical college level. The research questions were; What are the pedagogical skills needed by MVM teachers and instructors for teaching ATS at technical college level? and What are the practical skills needed by MVM teachers and instructors for teaching ATS at technical college level? were used to guide in the conduct of the study. The null hypothesis was tested at 0.05 level of significance. A 58 item questionnaire which was face validated by three experts from the Department of Vocational and Technology Education, Abubakar Tafawa Balewa University, Bauchi State Nigeria and pilot-tested on twelve respondents from Government Technical College, Gombe, Gombe State that were not part of the study which yielded a Cronbach alpha coefficient of 0.993 was used to determine the internal consistency was used to collect data for the study. The data was analyzed using mean and standard deviation. The data support the conclusion that teachers do not feel confidence of their pedagogical and practical skills. As a result of the above revelation, the following implications arise. Teachers of MVM program in the technical colleges needed training and retraining in pedagogical as well as practical skills to enable them to perform their professional responsibilities in their practice. The pre-service training received by the teachers was found to be rickety and completely defective, which might not perfectly prepare them for effective job performance. The MVM teachers need to be retrained in order to update their knowledge, skills and competencies with respect to pedagogical and practical skills to enable be able to teach the learners efficiently and effectively, so that the learners can graduate as competent craftsmen, technicians and technologist. &nbsp

Biosorption of zinc from aqueous solution by Penicillium sp immobilised in Calcium alginate

The biosorption of Zn (II) in aqueous solution by alginate- immobilised Penicillium sp was investigated. Parameters which are responsible for optimizing sorption such as: initial pH of the solution, contact time and initial Zn (II) concentrations were varied and observed. The results were fitted into Langmuir, Freundlich and Temkin Isotherms. Optimization parameters were focused on initial solution pH, contact time and initial Zn (II) concentrations. Results were fitted to Langmuir, Freundlich and Temkin isotherms. The maximum Zn (II) biosorption of 94.29 % in aqueous solution was achieved at pH of 6.0, contact time of 120 minutes and initial Zn (II) concentration of 1 mg/L. The experimental results showed the R2 values for the isotherms to be 0.7591, 0.7780 and 0.9552 respectively for the Langmuir, Freundlich and Temkin isotherms indicating that the results fitted the Temkin isotherm more than the other isotherms. The maximum biosorption capacity was 3.78 mgg-1 while the value of n, a measure of biosorption intensity, was 1.43 Lmg-1 showing a favorable adsorption. These results show that immobilized Penicillium sp is a good biosorbent for the removal of Zn (II) from waste water with minimal environmental impact

Levels of antinutritional factors in some wild edible fruits of Northern Nigeria

Sixteen wild fruits commonly consumed in northern Nigeria were assessed chemically for the presence of oxalate, phytate, saponin, and tannin. The highest level of oxalate was found in Zizyphus spinachristi,Zizyphus mauritiana and Balanite aegyptiaca (16.20±2.12%, 15.50±1.50% and 14.50±2.08%, respectively). Phytate was highest in Sclerocarya birrea (3.56±0.54%) and Haematostaphis barteri(3.30±0.10%). B. aegyptiaca, Detarium microcarpum and Parkia biglobosa had the highest saponin values of 16.01±0.02, 12.10±0.05 and 12.23±0.46% respectively. While tannin was highest in B.aegyptiaca (7.40±0.14%), closely followed by Hyphaena thebaica (6.39±0.5%) and Borassus aethiopum (5.90±0.13%). Though these antinutrients can interfere with nutrients utilization when in highconcentration, the values obtained for the fruits analysed were not up to the toxic levels of the antinutrients. Fruits such as Vittaleria paradoxum, Adansonia digitata, Diospyros mespiliformis Phoenixdactylifera and young shoot of Bor. aethiopum are highly recommended for consumption as they contain low amount of the antinutrients analysed

The effect of “Gadagi” tea on liver function and serum glucose concentration in albino rats

Effect of oral administration of “Gadagi” tea on liver function and serum glucose concentration was assessed on thirty (30) healthy non – pregnant female albino rats. The animals were grouped and administered different doses (mg/kg) i.e. (low dose; 0.75mg/kg for “Sak,” 1.40mg/kg for “Sada” and 2.10mg/kg for “magani.” Standard dose; 1.50mg/kg for “Sak,” 2.80mg/kg for “Sada” and 4.20mg/kg for “magani.” High dose; 3.00mg/kg for “Sak,” 5.60mg/kg for “Sada” and 8.30mg/kg for “magani”) for a period of one week. Animals that were not administered the tea constituted the control group. At the end of one week, the animals were sacrificed and their serum alanine transaminase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP), bilirubin (total and direct) and glucose levels were determined. Mean serum glucose level of the control animals was significantly higher (

AIRBODS: Findings and guidance for airborne infection resilience, A publication of Airborne Infection Reduction through Building Operation and Design for SARS-CoV-2 (AIRBODS)

This guidance provides insights into airborne infection risks and proposes mitigation measures to improve airborne infection resilience of indoor and semi-outdoor spaces. In some poorly-ventilated and/or highly occupied spaces, the provision of increased ventilation performance can be the key to reducing airborne infection risk down to 'acceptable' (although currently undefined)levels. This is a complex area of study with many areas of uncertainty that form the basis of ongoing research. That said, the AIRBODS programme, in the context of the global research efforts associated with the COVID-19 pandemic, has generated a sound basis for improving airborne infection resilience. Key aspects of the guide with its many recommendations include: • Experiments carried out in a test chamber showing how screens can improve or, even, worsen airborne infection risk. • Field studies undertaken as part of the Events Research Programmewhichunderpinned the opening up of the UK hospitality sector in the summer of 2021. Good practice advice is provided on how to drive high-resolution CO2 and microbiological studies and then appropriately interpret results. • Analyticalmodelswere developed to understand how infection risk, using a mass balance approach with many different parameters, might be mitigated in some circumstances when compared to reference spaces. These models were then developed into a 'full building' tool which can be downloaded as part of this guidance. • Computational fluid dynamics (CFD) models were developed to provide insights into the physics of droplets or aerosols at microscale. Following completion of a test chamber validation exercise, models were developed to investigate breathing or coughing mannequins at single human moving towards audience or crowd scale. Local ventilation effectiveness and associated airborne infection risk aspects of some real spaces may significantly differ from assumed 'fully-mixed' equivalent spaces. This, along with a number of other issues, will form part of ongoing research activities. • Focus groups were also used to provide some wider context and support some of our recommendations. AIRBODS has produced a repository of data and modelling methods with the mindset of enabling building professionals to inform their design and operation decisions towards improving airborne infection resilience in their buildings

Gastric atrophy and oesophageal squamous cell carcinoma: Possible interaction with dental health and oral hygiene habit

Background:Gastric fundal atrophy has been hypothesised to increase the risk of oesophageal squamous cell carcinoma (OSCC), but studies have shown inconsistent results.Methods:We measured serum pepsinogen I (PGI) and pepsinogen II (PGII) among 293 incident cases and 524 matched neighbourhood controls in a high-risk area of Northern Iran. Conditional logistic regression model was used to estimate odds ratios (ORs) and their 95% confidence intervals (CIs).Results:After controlling for age, sex, residence area and other potential confounders, gastric atrophy (defined by a validated criterion, PGI <55 μg dl-1) was associated with a two-fold increased risk (OR=2.01, 95% CI: 1.18, 3.45) of OSCC in the absence of nonatrophic pangastritis (defined as PGII <11.8 μg dl-1). Stratification by PGII decreased the misclassification errors due to cancer-induced gastritis. Presence of both poor dental health, indicated by higher than median sum of decayed, missing, and filled teeth (DMFT score), and gastric atrophy further increased the risk of OSCC (OR=4.15, 95% CI: 2.04, 8.42) with relative excess risk due to interaction (RERI) of 1.47 (95% CI: 1.15, 4.1). Coexistence of poor oral hygiene habit with gastric atrophy elevated OSCC risk eight times (OR=8.65, 95% CI: 3.65, 20.46) and the additive interaction index was marginally statistically significant (RERI=4.34, 95% CI: 1.07, 9.76).Conclusion:Gastric atrophy is a risk factor for OSCC, and poor dental health and oral hygiene habit may act synergistically in increasing the risk. © 2012 Cancer Research UK