9 research outputs found
Experimental Characterization of Maize Cob and Stalk Based Pellets for Energy Use
The quest for alternative energy sources is gradually shifting from natural fossil fuel to alternative bio-resources especially agricultural waste products due to their reduced pollution risk and sustainability. This study seeks to investigate the suitability of plant residue pellets to produce biomass. The plant residues investigated include corn cob and corn stalk. Three samples produced include 100% granulated corn cob residues, 100% granulated stalks and a composite of 50:50% granulated corn cobs and stalk residues. The mixed residues were pelletized using cassava starch as a binder. The pellets were experimentally analyzed using ultimate, proximate and calorimetry analyses. Among three sets of maize residue pellets investigated, the result of the cob-stalk 50:50% combination show that it has 0.64% nitrogen, 48.57% carbon, 0.38% Sulphur, 6.22% hydrogen, 55.81% oxygen, 3.25% moisture content, 2.20% ash content, 80.0% volatile matter, 17.80% fixed carbon percentage, HHV of 32.9 kJ/kg, an average CO2 value of 563±50 PPM, an average CO value of 100±50 PPM, an average value of 69±4% relative humidity and an average temperature of 27.5±0.5%. The study reiterates that corn stalk is a good bio-fuel and should be encouraged to address the current energy shortfalls in the country
SOCIAL AND ERGONOMIC EVALUATION OF MOTORCYCLE PROTECTIVE ISOLATION SHIELD FOR REDUCING COMMUNITY SPREAD OF COVID-19
Coronavirus (COVID-19) pandemic have rapidly evolved into a situation with profound effects on lifestyle and travel worldwide, ranging from a dramatic decrease in the patronage of formal public transport modes to an unprecedented increase in the usage of informal public transport modes. It is the main goal of this study to adapt a Motorcycle Protective Isolation Shield (MPIS) on a motorcycle for the reduction of community spread of COVID-19. MPIS was designed according to the anthropometry data obtained from motorcycle riders and passengers; and was fabricated using locally available materials. Anthropometry data used for the MPIS frame were sitting height (SH) and popliteal height (PH) of both motorcycle riders and passengers while seat depth (SD) of motorcycle riders and buttock knee length (BKL) of motorcycle passengers were used to locate the position of the MPIS mounted on the motorcycle. The 50% of the anthropometry data used for the design of MPIS is SH=800.00 mm, PH=500.00 mm, SD=300.00 mm and BKL=550.00 mm. The uncertainty modelling of motorcycle accident occurrence reveals the effect of higher speeds and the adapted MPIS during riding. The probability of occurrence of fatal crash, major crash and minor crash of motorcycle accident was 36.3%, 35.3% and 28.4%, respectively. The MPIS showed satisfactory post-riding assessment in terms of riding stability; riding, steering, and sitting convenience; and riding comfort for both the riders and passengers. It will be a good protection for motorcycle riders against the risk of COVID-19 and other air-borne infections
Anthropometric studies for designing to fit gari-frying workers
Work system and product design require anthropometric data of the user population relevant to the facility in order to have safe operation in service as well as increase user satisfaction and efficiency. Designing to fit gari-frying workers in each of the southwestern states in Nigeria is geared towards this end. The age, weight and twenty-five body dimensions of 120 gari-frying workers in Lagos, Ogun, Oyo, Osun, Ondo and Ekiti, selected by random sampling, were measured. The body dimensions include stature, shoulder height, sitting height, eye height, forward grip reach, buttock-popliteal height, buttock-knee length, knee height, thigh clearance, forearm-to-forearm breadth, waist depth, elbow rest height, knuckle height, elbow grip length, hip breadth, hand length, hand breadth, hand thickness, grip span and lumbar height. SPSS 20 software was used to perform statistical analysis to determine the mean, standard deviation, minimum and maximum values, 2nd, 5th, 25th, 50th, 75th and 95th percentiles for each state. Ogun state was used as a control, against which means of body dimension data, collected from other states, were compared using paired sample t-test. The results revealed that some of the body dimensions showed significant difference across the states at P≤0.05 with Oyo having more anthropometric parameters that differ from that of Ogun and Ondo having the least. Between 11.42% and 24.25% difference in the mean age, weight and lumbar height was observed in all the states. Osun state has the highest mean BMI and BSA values of 32.38 kg/m2 and 1.82 m2, respectively. These results are the required data for the design of facility and products for gari-frying workers as well as in similar women workspaces, especially in processing centres
Distinct monkeypox virus lineages co-circulating in humans before 2022
The 2022 global mpox outbreak raises questions about how this zoonotic disease established effective human-to-human transmission and its potential for further adaptation. The 2022 outbreak virus is related to an ongoing outbreak in Nigeria originally reported in 2017, but the evolutionary path linking the two remains unclear due to a lack of genomic data between 2018, when virus exportations from Nigeria were first recorded, and 2022, when the global mpox outbreak began. Here, 18 viral genomes obtained from patients across southern Nigeria in 2019-2020 reveal multiple lineages of monkeypox virus (MPXV) co-circulated in humans for several years before 2022, with progressive accumulation of mutations consistent with APOBEC3 activity over time. We identify Nigerian A.2 lineage isolates, confirming the lineage that has been multiply exported to North America independently of the 2022 outbreak originated in Nigeria, and that it has persisted by human-to-human transmission in Nigeria for more than 2 years before its latest exportation. Finally, we identify a lineage-defining APOBEC3-style mutation in all A.2 isolates that disrupts gene A46R, encoding a viral innate immune modulator. Collectively, our data demonstrate MPXV capacity for sustained diversification within humans, including mutations that may be consistent with established mechanisms of poxvirus adaptation.</p
Emergence and spread of two SARS-CoV-2 variants of interest in Nigeria.
Identifying the dissemination patterns and impacts of a virus of economic or health importance during a pandemic is crucial, as it informs the public on policies for containment in order to reduce the spread of the virus. In this study, we integrated genomic and travel data to investigate the emergence and spread of the SARS-CoV-2 B.1.1.318 and B.1.525 (Eta) variants of interest in Nigeria and the wider Africa region. By integrating travel data and phylogeographic reconstructions, we find that these two variants that arose during the second wave in Nigeria emerged from within Africa, with the B.1.525 from Nigeria, and then spread to other parts of the world. Data from this study show how regional connectivity of Nigeria drove the spread of these variants of interest to surrounding countries and those connected by air-traffic. Our findings demonstrate the power of genomic analysis when combined with mobility and epidemiological data to identify the drivers of transmission, as bidirectional transmission within and between African nations are grossly underestimated as seen in our import risk index estimates
The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance.
Investment in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing in Africa over the past year has led to a major increase in the number of sequences that have been generated and used to track the pandemic on the continent, a number that now exceeds 100,000 genomes. Our results show an increase in the number of African countries that are able to sequence domestically and highlight that local sequencing enables faster turnaround times and more-regular routine surveillance. Despite limitations of low testing proportions, findings from this genomic surveillance study underscore the heterogeneous nature of the pandemic and illuminate the distinct dispersal dynamics of variants of concern-particularly Alpha, Beta, Delta, and Omicron-on the continent. Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve while the continent faces many emerging and reemerging infectious disease threats. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century
The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance
INTRODUCTION
Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic.
RATIONALE
We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs).
RESULTS
Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants.
CONCLUSION
Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century
A comparative study of physical properties of selected rice varieties in Nigeria
Rice is now the main food for about 35 million people in Nigeria, and consumption is increasing faster than that of any other food crop in many countries in Africa. This study provided essential engineering data on the physical properties of selected varieties of local rice in Nigeria. Some selected physical properties of Igbemo, Ofa-da and Abakaliki rice varieties at harvest, market, and storage conditions were evaluated as a function of moisture content. The latter ranged from 12.38 to 25.69% (dry base). We also determined the physical properties of the rice samples, such as moisture content, linear dimensions, geometric mean diameter, arithmetic mean diameter, surface area, aspect ratio, sphericity, bulk density, and hundred kernel weights. A result of the linear dimensions for the major diameter was 8.4–10.3 mm, 6.4–6.55 mm, and 5.9–7.4 mm for harvested, marketed, and stored rice, respec-tively. The minor diameter ranged from 2.70 to 3.29 mm, 2.49 to 2.63 mm, and 2.56 to 2.74 mm, and the intermedi-ate diameter of the rice varieties at harvest, market, and storage conditions was 1.92–2.29 mm, 1.90–2.02 mm, and 1.87–1.99 mm, respectively. Depending on the conditions and varieties, the bulk density, true density, and porosity, was observed to be between 0.59 to 0.90 g/cm3, 2.28 to 5.57 g/cm3 and 70.38 to 85.35% respectively
Evaluation of rural transportation technology: a case study of bicycle and motorcycle trailers
Transportation of goods in rural communities, especially from farms, is one of the major bottlenecks experienced by rural
dwellers. Bicycle and motorcycle trailers have been a major intervention proposed by several studies but, this technology has
not been fully adopted and it has no detailed evaluation report. This study, therefore, evaluates the performance of different
bicycle and motorcycle trailer designs. Three different designs of bicycle trailers (fixed plate design (FPD), convertible
plate design (CPD) and wire mesh design (WMD)) and two designs of motorcycle trailers (FPD and CPD) were developed.
Four performance evaluation tests (laden mass, forward speed, pull and haulage tests and a computer-based simulation of
stress/strain analysis) were carried out. The optimum load capacity (OLC) of WMD bicycle trailer is 100 kg at a speed of 5.2
– 6.3 km/hr, while that of FPD and CPD bicycle trailers are 100 kg at a speed of 3.8 - 4.2 km/hr. The OLC for the FPD and CPD
motorcycle trailer was 200 kg at a speed of 6.2 – 8.4 km/hr. Static structural analysis of the trailer chassis shows that the
maximum stress and strain of the trailers were 2.95 × 106 Pa and 8.22 × 10-6 mm, respectively. This study shows the suitability
of the bicycle and motorcycle trailers in small-scale goods conveyance and its suitability for the rural community