Approximation of the Cox survival regression model by MCMC Bayesian hierarchical Poisson modelling of factors associated with childhood mortality in Nigeria

The need for more pragmatic approaches to achieve sustainable development goal on childhood mortality reduction necessitated this study. Simultaneous study of the influence of where the children live and the censoring nature of children survival data is scarce. We identified the compositional and contextual factors associated with under-five (U5M) and infant (INM) mortality in Nigeria from 5 MCMC Bayesian hierarchical Poisson regression models as approximations of the Cox survival regression model. The 2018 DHS data of 33,924 under-five children were used. Life table techniques and the Mlwin 3.05 module for the analysis of hierarchical data were implemented in Stata Version 16. The overall INM rate (INMR) was 70 per 1000 livebirths compared with U5M rate (U5MR) of 131 per 1000 livebirth. The INMR was lowest in Ogun (17 per 1000 live births) and highest in Kaduna (106), Gombe (112) and Kebbi (116) while the lowest U5MR was found in Ogun (29) and highest in Jigawa (212) and Kebbi (248). The risks of INM and U5M were highest among children with none/low maternal education, multiple births, low birthweight, short birth interval, poorer households, when spouses decide on healthcare access, having a big problem getting to a healthcare facility, high community illiteracy level, and from states with a high proportion of the rural population in the fully adjusted model. Compared with the null model, 81% vs 13% and 59% vs 35% of the total variation in INM and U5M were explained by the state- and neighbourhood-level factors respectively. Infant- and under-five mortality in Nigeria is influenced by compositional and contextual factors. The Bayesian hierarchical Poisson regression model used in estimating the factors associated with childhood deaths in Nigeria fitted the survival data.Publisher PDFPeer reviewe

Studies on Control of Hazardous Noise from Portable 650 VA Power Generator

Experimental studies on the assessment and control of near-field noise levels due to the operation of a portable 650 VA power generator were undertaken at a residential building in Ara village, Moro local government, area of Kwara State. Smart sensor sound level meter AR824 (30-130 dB), meter rule and stop watch were used to measure the noise level produced at every two minutes risen time intervals for seven hundred and twenty minutes at ten different locations of one meter intervals. The background noise level of the environment was first taken and reported to be 47.60. The data obtained were analysed with Matlab R2010a. The results revealed that the 650 VA generating plant is safe for use when it is positioned at least 3 meters away to the building, offices, shops and so on

Synthesis and Characterization of Graphene-Cu Composite Via Hydrothermal Method

In this paper, graphene-copper composite was synthesized via hydrothermal method using different compositions from 5 to 25%. The grain size and copper composition are observed to decrease proportionally to increase in band gap. The effect of composition fluctuate the peaks shift. The peak increased linearly with increasing temperature for each composition. The band gap reduces with increasing temperature for each composition. Short calcined duration on samples is observed to cause a little lower band gap value than that of longer duration. The thermal treatment of graphene oxide (GO) has been observed to cause changes in its quality, size and shape. &nbsp

A Proposal for Multidisciplinary Tele-rehabilitation in the Assessment and Rehabilitation of COVID-19 survivors

A global pandemic of a new highly contagious disease called COVID-19 resulting from coronavirus (severe acute respiratory syndrome (SARS)-Cov-2) infection was declared in February 2020. Though primarily transmitted through the respiratory system, other organ systems in the body can be affected. Twenty percent of those affected require hospitalization with mechanical ventilation in severe cases. About half of the disease survivors have residual functional deficits that require multidisciplinary specialist rehabilitation. The workforce to deliver the required rehabilitation input is beyond the capacity of existing community services. Strict medical follow-up guidelines to monitor these patients mandate scheduled reviews within 12 weeks post discharge. Due to the restricted timeframe for these events to occur, existing care pathway are unlikely to be able to meet the demand. An innovative integrated post-discharge care pathway to facilitate follow up by acute medical teams (respiratory and intensive care) and a specialist multidisciplinary rehabilitation team is hereby proposed. Such a pathway will enable the monitoring and provision of comprehensive medical assessments and multidisciplinary rehabilitation. This paper proposes that a model of tele-rehabilitation is integrated within the pathway by using digital communication technology to offer quick remote assessment and efficient therapy delivery to these patients. Tele-rehabilitation offers a quick and effective option to respond to the specialist rehabilitation needs of COVID-19 survivors following hospital discharge

Determination of Selected Heavy Metals In Seasonal River In Maru Town, Zamfara State, Nigeria.

The presence of heavy metals in our environment has been of great concern because of their toxicity when their concentration is more than the permissible level. The main threats to human health from heavy metals are associated with exposure to Lead and Cadmium. These metals have been extensively studied and their effect on human health regularly monitored and reviewed by international bodies such as the WHO and USEPA. Total levels of Cd, Pb, Cu, Zn and Cr were determined in seasonal river in the eastern part of Maru using Flame Atomic Absorption Spectrophotometer (FAAS). The results of total metals concentration (ppm) in the river were 0.0211±0.0014, 0.177±0.0004, 0.0201±0.0031, 1.1367±0.0493 and 0.0058±0.0003 for Cd, Pb, Cu, Zn and Cr respectively. The study showed that the sample was contaminated with Zn when compared to others. The level of Cd and Pb were high when compared to their safety limit (0.01 and 0.10) by U.S.E.P.A. Keywords: Maru, Heavy Metals, Seasonal Rivers, Contamination

Numerical Modeling and Evaluation of Involute Curve Length of a Spur Gear Tooth to Maintain Constant Velocity Ratio While in Motion

Numerical modeling and values of the involutes curve length for a spur gear has been carried out using polar coordinate principles and application of calculus theorems. A set of values for base radius of the gear were considered from 10mm, 20mm, 30mm, 40mm and 50mm. The study also considered a pressure angle of 10°, 20°, 30°, 40°, and 50° for this set of values. The result of the length of involutes curve obtained at a pressure angle of 10° showed a significant increase in the length of the curve generated as the base radius increases that is at10° and for the set of the base radius values, the length obtained are:0.1555mm,0.311mm,0.4665mm,0.622mm and 0.7775mm. The result also revealed that at higher pressure angle of 50°, a better length of the curve was equally generated as seen from the plot.That is at 50° and with the base radius of 10mm, 20mm, 30mm, 40mm, and 50mm, the corresponding length of involutes are 7.1014mm, 14.203mm, 21.3045mm, 28.406mm and 35.5075mm. This equally validate the direct proportionality of length of curve as the square of tan a from equation

Postharvest Losses of Tomato (Solanum Lycopersicum) in the Open Markets in Ibadan Metropolis

Postharvest losses of tomato pose serious threat on the economic viability of actors in the tomato production chain in Nigeria. Therefore, postharvest losses of tomato among marketers in Ibadan Metropolis of Oyo State Nigeria were investigated by the researchers. One hundred and twenty tomato marketers were chosen from the five food markets in Ibadan metropolis through a simple random sampling technique. The study adopted linear regression and descriptive statistics to analyze data. The outcomes of the investigation show that females were 92.5% and 88.3% were married. Capital is primarily raised through cooperative societies (57.5%). Postharvest losses of tomato accounted for 18.9% of purchase which represents ₦124,800/day. The major causes of PHLs are poor packaging (100%) and poor storage (100%) by the tomato marketers. Meanwhile, all the respondents (100%) adopted sorting to reduce PHLs of tomato. The regression analysis showed that education has a significant effect to reduce PHLs of tomato. The study concluded that huge postharvest and monetary losses of tomato are experienced by the tomato marketers. The study recommends provision of quality postharvest handling education to tomato marketers as a way of reducing PHLs of tomato in Ibadan

Study of the Performances of Nano-Case Treatment Cutting Tools on Carbon Steel Work Material during Turning Operation

The degree of holding temperature and time play a major role in nano-case treatment of cutting tools which immensely contributed to its performance during machining operation. The objective of this research work is to carryout comparative study of performance of nano-case treatment tools developed using low and medium carbon steel as work piece. Turning operation was carried out under two different categories with specific work piece on universal lathe machine using HSS cutting tools 100 mm x 12mm x 12mm that has been nano-case treated under varying conditions of temperatures and timeof 800,850, 900, 950oC and 60, 90, 120 mins respectively. The turning parameters used in evaluating this experiment were cutting speed of 270, 380 and 560mm/min, feed rate of 0.15, 0.20 and 0.25 mm/min, depth of cut of 2mm, work piece diameter of 25mm and rake angle of 7o each at three levels. The results of comparative study of their performances revealed that the timespent in the machining of low carbon steel material at a minimum temperature and time of800°C, 60 mins were1.50, 2.17 mins while at maximum temperature and time of 950°C , 120 mins were 1.19, 2.02 mins. It was also observed that at a corresponding constant speed of 270,380 and 560mm/min at higher temperature and time, a relative increased in the length of cut were observed. Critical observation of the result showed that at higher case hardening temperature and time (950°C/120mins), the HSS cutting tool gave a better performance as lesser time was consumed during the turning operation

Design of Optimal Hybrid Renewable Energy System for Sustainable Power Supply to Isolated-grid Communities in North Central, Nigeria

The study analyzed the feasibility and techno-economic viability of renewable electricity generation from wind and solar standalone systems, and as hybrid facilities in six states across North-central, Nigeria. 24 years’ daily solar and wind data were sourced from system as a test case for university communities with an equivalent consumption of 28.9 MWh/day. The electricity load demand adopted was based on an audit of electricity generation conducted for the University of Lagos main campus. The supply architecture adopted in this study excludes the use of heavy equipment or machinery loads and only caters for the institutions’ base loads. An evaluation of the design that will optimally match the daily load demand of the communities with LOLP ranging from 1 to 50% was undertaken. HOMER software was employed as the optimisation tool together with other statistical and analytical variations to determine best design for the sites with diesel standalone facility taken as the base system. The outcome showed that hybrid generation system fared better than the standalone PV or Wind energy system at Abuja, Ilorin, Lokoja and Makurdi, while the wind standalone system was the optimal generation technology at Minna and Jos. Further to this, values of the levelized cost of energy showed that adopting wind resources (as standalone or in hybrid format with PV) for power generation at the sites/institutions at Minna and Jos, is more viable than the use of diesel generators

Development of a Human Powered Pedal Washing MACHINE

Human powered pedal washing machine has been designed using materials suitable for its application. An existing bicycle was used as the pedal and other parts of the machine such as the drum, the frame was fabricated using galvanized steel. The material selection was put into consideration, such as corrosion because of the machine’s involvement with water. The human powered pedal washing machine was tested with a used dirty Laboratory coat. The pedaling washing was first done for the first 15 minutes, using water and sunlight detergent soap. There was a partial cleaning of the Laboratory coat, though the coat was very dirty. Another round of washing was done after which the first washing water was drained out through the outlet part of the machine. The second washing was excellent because the Laboratory coat was clean. The human powered pedal washing machine performed well with all the designed parts functioning well. This is an eco-friendly machine, maintenance cost free, energy conservation machine and highly sustainable for underdeveloped nations of the world