17 research outputs found

    Analysis of the Effect of Distributed Generation on Loss Reduction in Electrical Distribution Network

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    Distribution network is said to be the most visual part of the electric production and the most observed by the utilities for investment, maintenance and operation. The system have been operated under stressed conditions due to limited structure and increasing day to day requirement of power consumption, which have a significant economic and social impact on the system. Due to the system high resistance to impendence ratio, large amount of power loss occur in the network. This loss is the most severity factors affecting the power quality delivered to the end users and depend on power network expansion and load complexity. Among the support methods available for power loss minimization in distribution network, strategic allocation of Distributed Generation (DG) in distribution system is widely considered a viable option. DGs are electrical sources connected to the power network located to consumer’s side but very small when compared with the centralized power plant. They can be in form of wind, mini-hydro, photovoltaic and fuel-based system such as fuel cells and micro-turbines. Therefore, in this study, different approaches for power loss minimization in electrical distribution system with the incorporation of DG by various researchers were reviewed. These approaches have become powerful tools to overcome the problem of power loss minimization in distribution system. Keywords: Distribution System, Power Loss. Distributed Generation, Power Consumption, Photovoltaic System, Centralized Power Plant. DOI: 10.7176/JETP/11-6-02 Publication date: November 30th 202

    Influence of hydrocolloids addition (carboxymethylcellulose and guargum)on some quality attributes of wheat and high quality cassava flour and itsbread making potentials

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    High quality cassava flour (HQCF) is now widely used production of baked foods in Nigeria but bread quality is impaired when it is used in the bread formulation. In order to overcome this problem, six breads samples were produced from wheat/HQCF/hydrocolloid:T0100%wheat flour(control);T190:9:CMC;T290:9:GG;T3,80:18:CMC;T4,80:18:GG;T570:27:CMC;T670:27:GG. The flour blends were analyzed for functional, colour and pasting properties while breads characteristics and sensory evaluation were performed in order to assess effect of hydrocolloids on bread. The results showed composite flour with hydrocolloids had the highest bulk density (0.704g/ml), water absorption capacity (2.98m/g), least gelation concentration (4.4g/g), oil absorption capacity (0.71m/g), while control had the highest swelling capacity (1.68g/g). Significant differences at p<0.05 were found on the pasting properties of addition of hydrocolloids with lower pasting temperature (71oC) and time (6.08 min). Bread quality attributes such as loaf volume, specific loaf volume, oven spring, crust colour, crumb colour and firmness of the fresh breads significantly improved with the addition of hydrocolloids compared with bread produced without improvers. The results show that high quality cassava flour could be incorporated up to 18% with carboxymethylcellulose at 2% level without affecting its overall acceptability and thereby enhance the potential for using locally produced flours in bread baking. Sensory score of bread from the addition of hydrocolloids were all acceptable by the panelist. The addition of hydrocolloids could be used as an effective means of improving the quality of gluten free bread

    Chemical and Mechanical Properties of Reinforcing Steel Bars from Local Steel Plants

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    Steel bars are important engineering materials for structural application. In Nigeria, due to incessant building collapse occurrences, it is important to further investigate some of the mechanical and chemical properties of reinforcing steel bars produced from scrap metals in order to ascertain their compliance with the required standard. Three diameters (10, 12 and 16 mm) of the reinforcing steel bars were chosen from each of the eight steel plants (A–H). Chemical composition analyses and mechanical tests (yield strength, ultimate tensile strength and percentage elongation) were performed using optical emission spectrometer and Instron Satec Series 600DX universal testing machine, respectively. Hardness values of the samples were obtained by conversion of tensile strength based on existing correlation. The results showed that carbon contents, hardness values, yield and ultimate tensile strengths of some of the steel bars were found to be higher than the BS4449, NIS and ASTM A706 standards. The steel bar samples were also found to possess good ductility with samples from steel plants C and D. By observation, all the 12 mm steel bars from steel plants A to H met the required ASTM and BS4449 standards except samples from plant G. This study revealed that most of the investigated reinforcing steel bars have reasonable yield strength, ultimate tensile strength, ductility and hardness properties when compared with the relevant local and international standards. Therefore, they are suitable for structural applications where strength and ductility will be of paramount interest

    Toasted Jatropha curcas seed meal in Nile tilapia (Oreochromis niloticus) diet: Effect on growth, economic performance, haematology, serum biochemistry and liver histology

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    The effect of dietary inclusion of differently timed dry heat-treated Jatropha curcas on the growth and economic performance of Nile tilapia, Oreochromis niloticus, was evaluated in a 56-day feeding trial. Five isonitrogenous and isolipidic dietary treatments (35% crude protein and 10% crude lipid) were made consisting of soybean meal (control) which was replaced by J. curcas seed meal toasted either 5 min or 10 min at 20 and 40% to make other four test diets. A total of 225 juveniles of O. niloticus were acclimatized for a week, weighed and allotted into five dietary treatments. Each treatment was replicated three times with fifteen fish per replicate. Fish were fed 5% body weight on two equal proportions per day for 56 days. Growth data were collected at two-week intervals. The results from the study indicated that there was significant difference (P0.05) in the different growth and economic performance parameters of fish fed CTR and fish fed D520T (5 min toasted, 20%). There was significant reduction in haematological and biochemical parameters of the blood of O. niloticus fed the different dietary treatments containing J. curcas seed meal. Based on economic and physiologic performance, soybean meal in Nile tilapia diet could be replaced up to 40% by 5-minute toasted J. curcass seed meal

    Effect of Micro Economic Factors on Residential Property Value in Birnin Kebbi, Kebbi State, Nigeria

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    The research aims to assess the microeconomic factors affecting residential property values in Birnin Kebbi. Property serves as an asset for any individual, as real estate is one of life\u27s primary goals. Besides the need to eat and drink, property also plays a crucial role in daily life. Property values are influenced by various factors, which can be either microeconomic or macroeconomic in nature, or both. Many microeconomic variables are related to property attributes and buyer demographic profiles. To achieve this aim, two objectives were formulated: (i) to examine the types of property and microeconomic factors affecting property values in the study area, and (ii) to assess the effect of microeconomic factors on residential property values. Both primary and secondary sources of data were used for data collection. Out of 377 questionnaires administered, 321 were retrieved. Simple random sampling and stratified random sampling methods were employed. Quantitative methods were used for data analysis, and all data gathered were analysed using descriptive statistics and the Likert scale. The study found that physical characteristics of residential properties, such as types of materials used, building design, room sizes, parking spaces, building age, and landscape, significantly influence property values. Additionally, the types of finishes (roofs, walls, ceilings, and floors), infrastructural facilities, and social amenities (number of toilets, electricity fittings, waste disposal and sewage, potable water supply, and various sanitation facilities) also play a role. The effects of microeconomic variables on property values in the study area include insecurity, increased traffic, property price changes, nuisances, environmental quality, property demand, and time consumption. The study recommends that prospective property developers ensure the use of standard building finishes to maximize returns on their investment in property value. Additionally, the government should introduce policies to ease difficulties in importing housing materials and promote the manufacture of local ones

    Burden of disease scenarios for 204 countries and territories, 2022–2050: a forecasting analysis for the Global Burden of Disease Study 2021

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    Background: Future trends in disease burden and drivers of health are of great interest to policy makers and the public at large. This information can be used for policy and long-term health investment, planning, and prioritisation. We have expanded and improved upon previous forecasts produced as part of the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) and provide a reference forecast (the most likely future), and alternative scenarios assessing disease burden trajectories if selected sets of risk factors were eliminated from current levels by 2050. Methods: Using forecasts of major drivers of health such as the Socio-demographic Index (SDI; a composite measure of lag-distributed income per capita, mean years of education, and total fertility under 25 years of age) and the full set of risk factor exposures captured by GBD, we provide cause-specific forecasts of mortality, years of life lost (YLLs), years lived with disability (YLDs), and disability-adjusted life-years (DALYs) by age and sex from 2022 to 2050 for 204 countries and territories, 21 GBD regions, seven super-regions, and the world. All analyses were done at the cause-specific level so that only risk factors deemed causal by the GBD comparative risk assessment influenced future trajectories of mortality for each disease. Cause-specific mortality was modelled using mixed-effects models with SDI and time as the main covariates, and the combined impact of causal risk factors as an offset in the model. At the all-cause mortality level, we captured unexplained variation by modelling residuals with an autoregressive integrated moving average model with drift attenuation. These all-cause forecasts constrained the cause-specific forecasts at successively deeper levels of the GBD cause hierarchy using cascading mortality models, thus ensuring a robust estimate of cause-specific mortality. For non-fatal measures (eg, low back pain), incidence and prevalence were forecasted from mixed-effects models with SDI as the main covariate, and YLDs were computed from the resulting prevalence forecasts and average disability weights from GBD. Alternative future scenarios were constructed by replacing appropriate reference trajectories for risk factors with hypothetical trajectories of gradual elimination of risk factor exposure from current levels to 2050. The scenarios were constructed from various sets of risk factors: environmental risks (Safer Environment scenario), risks associated with communicable, maternal, neonatal, and nutritional diseases (CMNNs; Improved Childhood Nutrition and Vaccination scenario), risks associated with major non-communicable diseases (NCDs; Improved Behavioural and Metabolic Risks scenario), and the combined effects of these three scenarios. Using the Shared Socioeconomic Pathways climate scenarios SSP2-4.5 as reference and SSP1-1.9 as an optimistic alternative in the Safer Environment scenario, we accounted for climate change impact on health by using the most recent Intergovernmental Panel on Climate Change temperature forecasts and published trajectories of ambient air pollution for the same two scenarios. Life expectancy and healthy life expectancy were computed using standard methods. The forecasting framework includes computing the age-sex-specific future population for each location and separately for each scenario. 95% uncertainty intervals (UIs) for each individual future estimate were derived from the 2·5th and 97·5th percentiles of distributions generated from propagating 500 draws through the multistage computational pipeline. Findings: In the reference scenario forecast, global and super-regional life expectancy increased from 2022 to 2050, but improvement was at a slower pace than in the three decades preceding the COVID-19 pandemic (beginning in 2020). Gains in future life expectancy were forecasted to be greatest in super-regions with comparatively low life expectancies (such as sub-Saharan Africa) compared with super-regions with higher life expectancies (such as the high-income super-region), leading to a trend towards convergence in life expectancy across locations between now and 2050. At the super-region level, forecasted healthy life expectancy patterns were similar to those of life expectancies. Forecasts for the reference scenario found that health will improve in the coming decades, with all-cause age-standardised DALY rates decreasing in every GBD super-region. The total DALY burden measured in counts, however, will increase in every super-region, largely a function of population ageing and growth. We also forecasted that both DALY counts and age-standardised DALY rates will continue to shift from CMNNs to NCDs, with the most pronounced shifts occurring in sub-Saharan Africa (60·1% [95% UI 56·8–63·1] of DALYs were from CMNNs in 2022 compared with 35·8% [31·0–45·0] in 2050) and south Asia (31·7% [29·2–34·1] to 15·5% [13·7–17·5]). This shift is reflected in the leading global causes of DALYs, with the top four causes in 2050 being ischaemic heart disease, stroke, diabetes, and chronic obstructive pulmonary disease, compared with 2022, with ischaemic heart disease, neonatal disorders, stroke, and lower respiratory infections at the top. The global proportion of DALYs due to YLDs likewise increased from 33·8% (27·4–40·3) to 41·1% (33·9–48·1) from 2022 to 2050, demonstrating an important shift in overall disease burden towards morbidity and away from premature death. The largest shift of this kind was forecasted for sub-Saharan Africa, from 20·1% (15·6–25·3) of DALYs due to YLDs in 2022 to 35·6% (26·5–43·0) in 2050. In the assessment of alternative future scenarios, the combined effects of the scenarios (Safer Environment, Improved Childhood Nutrition and Vaccination, and Improved Behavioural and Metabolic Risks scenarios) demonstrated an important decrease in the global burden of DALYs in 2050 of 15·4% (13·5–17·5) compared with the reference scenario, with decreases across super-regions ranging from 10·4% (9·7–11·3) in the high-income super-region to 23·9% (20·7–27·3) in north Africa and the Middle East. The Safer Environment scenario had its largest decrease in sub-Saharan Africa (5·2% [3·5–6·8]), the Improved Behavioural and Metabolic Risks scenario in north Africa and the Middle East (23·2% [20·2–26·5]), and the Improved Nutrition and Vaccination scenario in sub-Saharan Africa (2·0% [–0·6 to 3·6]). Interpretation: Globally, life expectancy and age-standardised disease burden were forecasted to improve between 2022 and 2050, with the majority of the burden continuing to shift from CMNNs to NCDs. That said, continued progress on reducing the CMNN disease burden will be dependent on maintaining investment in and policy emphasis on CMNN disease prevention and treatment. Mostly due to growth and ageing of populations, the number of deaths and DALYs due to all causes combined will generally increase. By constructing alternative future scenarios wherein certain risk exposures are eliminated by 2050, we have shown that opportunities exist to substantially improve health outcomes in the future through concerted efforts to prevent exposure to well established risk factors and to expand access to key health interventions

    Global age-sex-specific mortality, life expectancy, and population estimates in 204 countries and territories and 811 subnational locations, 1950–2021, and the impact of the COVID-19 pandemic: a comprehensive demographic analysis for the Global Burden of Disease Study 2021

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    Background: Estimates of demographic metrics are crucial to assess levels and trends of population health outcomes. The profound impact of the COVID-19 pandemic on populations worldwide has underscored the need for timely estimates to understand this unprecedented event within the context of long-term population health trends. The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 provides new demographic estimates for 204 countries and territories and 811 additional subnational locations from 1950 to 2021, with a particular emphasis on changes in mortality and life expectancy that occurred during the 2020–21 COVID-19 pandemic period. Methods: 22 223 data sources from vital registration, sample registration, surveys, censuses, and other sources were used to estimate mortality, with a subset of these sources used exclusively to estimate excess mortality due to the COVID-19 pandemic. 2026 data sources were used for population estimation. Additional sources were used to estimate migration; the effects of the HIV epidemic; and demographic discontinuities due to conflicts, famines, natural disasters, and pandemics, which are used as inputs for estimating mortality and population. Spatiotemporal Gaussian process regression (ST-GPR) was used to generate under-5 mortality rates, which synthesised 30 763 location-years of vital registration and sample registration data, 1365 surveys and censuses, and 80 other sources. ST-GPR was also used to estimate adult mortality (between ages 15 and 59 years) based on information from 31 642 location-years of vital registration and sample registration data, 355 surveys and censuses, and 24 other sources. Estimates of child and adult mortality rates were then used to generate life tables with a relational model life table system. For countries with large HIV epidemics, life tables were adjusted using independent estimates of HIV-specific mortality generated via an epidemiological analysis of HIV prevalence surveys, antenatal clinic serosurveillance, and other data sources. Excess mortality due to the COVID-19 pandemic in 2020 and 2021 was determined by subtracting observed all-cause mortality (adjusted for late registration and mortality anomalies) from the mortality expected in the absence of the pandemic. Expected mortality was calculated based on historical trends using an ensemble of models. In location-years where all-cause mortality data were unavailable, we estimated excess mortality rates using a regression model with covariates pertaining to the pandemic. Population size was computed using a Bayesian hierarchical cohort component model. Life expectancy was calculated using age-specific mortality rates and standard demographic methods. Uncertainty intervals (UIs) were calculated for every metric using the 25th and 975th ordered values from a 1000-draw posterior distribution. Findings: Global all-cause mortality followed two distinct patterns over the study period: age-standardised mortality rates declined between 1950 and 2019 (a 62·8% [95% UI 60·5–65·1] decline), and increased during the COVID-19 pandemic period (2020–21; 5·1% [0·9–9·6] increase). In contrast with the overall reverse in mortality trends during the pandemic period, child mortality continued to decline, with 4·66 million (3·98–5·50) global deaths in children younger than 5 years in 2021 compared with 5·21 million (4·50–6·01) in 2019. An estimated 131 million (126–137) people died globally from all causes in 2020 and 2021 combined, of which 15·9 million (14·7–17·2) were due to the COVID-19 pandemic (measured by excess mortality, which includes deaths directly due to SARS-CoV-2 infection and those indirectly due to other social, economic, or behavioural changes associated with the pandemic). Excess mortality rates exceeded 150 deaths per 100 000 population during at least one year of the pandemic in 80 countries and territories, whereas 20 nations had a negative excess mortality rate in 2020 or 2021, indicating that all-cause mortality in these countries was lower during the pandemic than expected based on historical trends. Between 1950 and 2021, global life expectancy at birth increased by 22·7 years (20·8–24·8), from 49·0 years (46·7–51·3) to 71·7 years (70·9–72·5). Global life expectancy at birth declined by 1·6 years (1·0–2·2) between 2019 and 2021, reversing historical trends. An increase in life expectancy was only observed in 32 (15·7%) of 204 countries and territories between 2019 and 2021. The global population reached 7·89 billion (7·67–8·13) people in 2021, by which time 56 of 204 countries and territories had peaked and subsequently populations have declined. The largest proportion of population growth between 2020 and 2021 was in sub-Saharan Africa (39·5% [28·4–52·7]) and south Asia (26·3% [9·0–44·7]). From 2000 to 2021, the ratio of the population aged 65 years and older to the population aged younger than 15 years increased in 188 (92·2%) of 204 nations. Interpretation: Global adult mortality rates markedly increased during the COVID-19 pandemic in 2020 and 2021, reversing past decreasing trends, while child mortality rates continued to decline, albeit more slowly than in earlier years. Although COVID-19 had a substantial impact on many demographic indicators during the first 2 years of the pandemic, overall global health progress over the 72 years evaluated has been profound, with considerable improvements in mortality and life expectancy. Additionally, we observed a deceleration of global population growth since 2017, despite steady or increasing growth in lower-income countries, combined with a continued global shift of population age structures towards older ages. These demographic changes will likely present future challenges to health systems, economies, and societies. The comprehensive demographic estimates reported here will enable researchers, policy makers, health practitioners, and other key stakeholders to better understand and address the profound changes that have occurred in the global health landscape following the first 2 years of the COVID-19 pandemic, and longer-term trends beyond the pandemic

    Global incidence, prevalence, years lived with disability (YLDs), disability-adjusted life-years (DALYs), and healthy life expectancy (HALE) for 371 diseases and injuries in 204 countries and territories and 811 subnational locations, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021

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    Background: Detailed, comprehensive, and timely reporting on population health by underlying causes of disability and premature death is crucial to understanding and responding to complex patterns of disease and injury burden over time and across age groups, sexes, and locations. The availability of disease burden estimates can promote evidence-based interventions that enable public health researchers, policy makers, and other professionals to implement strategies that can mitigate diseases. It can also facilitate more rigorous monitoring of progress towards national and international health targets, such as the Sustainable Development Goals. For three decades, the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) has filled that need. A global network of collaborators contributed to the production of GBD 2021 by providing, reviewing, and analysing all available data. GBD estimates are updated routinely with additional data and refined analytical methods. GBD 2021 presents, for the first time, estimates of health loss due to the COVID-19 pandemic. Methods: The GBD 2021 disease and injury burden analysis estimated years lived with disability (YLDs), years of life lost (YLLs), disability-adjusted life-years (DALYs), and healthy life expectancy (HALE) for 371 diseases and injuries using 100 983 data sources. Data were extracted from vital registration systems, verbal autopsies, censuses, household surveys, disease-specific registries, health service contact data, and other sources. YLDs were calculated by multiplying cause-age-sex-location-year-specific prevalence of sequelae by their respective disability weights, for each disease and injury. YLLs were calculated by multiplying cause-age-sex-location-year-specific deaths by the standard life expectancy at the age that death occurred. DALYs were calculated by summing YLDs and YLLs. HALE estimates were produced using YLDs per capita and age-specific mortality rates by location, age, sex, year, and cause. 95% uncertainty intervals (UIs) were generated for all final estimates as the 2·5th and 97·5th percentiles values of 500 draws. Uncertainty was propagated at each step of the estimation process. Counts and age-standardised rates were calculated globally, for seven super-regions, 21 regions, 204 countries and territories (including 21 countries with subnational locations), and 811 subnational locations, from 1990 to 2021. Here we report data for 2010 to 2021 to highlight trends in disease burden over the past decade and through the first 2 years of the COVID-19 pandemic. Findings: Global DALYs increased from 2·63 billion (95% UI 2·44–2·85) in 2010 to 2·88 billion (2·64–3·15) in 2021 for all causes combined. Much of this increase in the number of DALYs was due to population growth and ageing, as indicated by a decrease in global age-standardised all-cause DALY rates of 14·2% (95% UI 10·7–17·3) between 2010 and 2019. Notably, however, this decrease in rates reversed during the first 2 years of the COVID-19 pandemic, with increases in global age-standardised all-cause DALY rates since 2019 of 4·1% (1·8–6·3) in 2020 and 7·2% (4·7–10·0) in 2021. In 2021, COVID-19 was the leading cause of DALYs globally (212·0 million [198·0–234·5] DALYs), followed by ischaemic heart disease (188·3 million [176·7–198·3]), neonatal disorders (186·3 million [162·3–214·9]), and stroke (160·4 million [148·0–171·7]). However, notable health gains were seen among other leading communicable, maternal, neonatal, and nutritional (CMNN) diseases. Globally between 2010 and 2021, the age-standardised DALY rates for HIV/AIDS decreased by 47·8% (43·3–51·7) and for diarrhoeal diseases decreased by 47·0% (39·9–52·9). Non-communicable diseases contributed 1·73 billion (95% UI 1·54–1·94) DALYs in 2021, with a decrease in age-standardised DALY rates since 2010 of 6·4% (95% UI 3·5–9·5). Between 2010 and 2021, among the 25 leading Level 3 causes, age-standardised DALY rates increased most substantially for anxiety disorders (16·7% [14·0–19·8]), depressive disorders (16·4% [11·9–21·3]), and diabetes (14·0% [10·0–17·4]). Age-standardised DALY rates due to injuries decreased globally by 24·0% (20·7–27·2) between 2010 and 2021, although improvements were not uniform across locations, ages, and sexes. Globally, HALE at birth improved slightly, from 61·3 years (58·6–63·6) in 2010 to 62·2 years (59·4–64·7) in 2021. However, despite this overall increase, HALE decreased by 2·2% (1·6–2·9) between 2019 and 2021. Interpretation: Putting the COVID-19 pandemic in the context of a mutually exclusive and collectively exhaustive list of causes of health loss is crucial to understanding its impact and ensuring that health funding and policy address needs at both local and global levels through cost-effective and evidence-based interventions. A global epidemiological transition remains underway. Our findings suggest that prioritising non-communicable disease prevention and treatment policies, as well as strengthening health systems, continues to be crucially important. The progress on reducing the burden of CMNN diseases must not stall; although global trends are improving, the burden of CMNN diseases remains unacceptably high. Evidence-based interventions will help save the lives of young children and mothers and improve the overall health and economic conditions of societies across the world. Governments and multilateral organisations should prioritise pandemic preparedness planning alongside efforts to reduce the burden of diseases and injuries that will strain resources in the coming decades. Funding: Bill &amp; Melinda Gates Foundation

    IMPACT OF TILLAGE PRACTICES ON PROPERTIES OF SOIL, EVAPOTRANSPIRATION AND PRODUCTIVITY OF COWPEA IN NIGERIA

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    Background: Tillage is one of the major threats to soil health which often results into soil physical degradation if not properly managed. Zero tillage is an alternative option from both economic and environmental protection of our soil resources points of view. Objective. To evaluate responses of cowpea (Vigna unguiculata) yield and evapotranspiration to different tillage practices. Methodology. The study was conducted in Obafemi Awolowo University, Ile-Ife Osun State, Nigeria using a replicated randomized complete block design with treatments consisting of Zero-tillage (ZT), Reduced tillage (RT), Conventional tillage + Mulch (CT + ML) and Conventional tillage (CT). Results. Soil penetration resistance (SPR) increased with the degree of soil manipulation during tillage practices. Penetration resistance (PR) across 15-30 cm in 2019 alone resulted in higher PR of 2.26 MPa for RT compared to 0.71, 0.72 and 0.79 MPa for ZT, CT + (ML and CT), respectively, approximately 218 %, 213 % and 186 % greater in RT than ZT, CT + ML and CT respectively. Implications. Cowpea production on sandy loam soil can be optimized with Zero tillage. Conclusion. Over a period of two years, ZT practice had the highest profit margin of $ 573, among the practices

    Właściwości fizyczne nasion baobabu (Adansonia digitata L.) w zależności od ich wilgotności

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    The research investigated physical properties of baobab seeds to determine suitable equipment for the processing of its seeds. Pods of baobab used in the study were collected at a local farm in Ilorin, North Central Nigeria. Physical properties of the samples, such as moisture contents, mass, axial dimensions, shape indices, true and bulk densities, porosity, angle of repose and surface area were determined. The results showed that physical properties of baobab seeds were stable for moisture content, ranging between 12 to 18% dry mass (dm). The 100 seed mass (g) and geometric mean diameter increased from 0.60 g to 0.62 g and 10.12 to 10.27 mm respectively, in the moisture range of 12 to 18% dm. Other studied ranges of physical properties ranges included: average length (12.22 to 12.63 mm), width (10.10 to 10.28 mm), thickness (8.23 to 8.42 mm,), sphericity, (81.23 to 82.56 mm), surface area (319.42 to 332.53 mm2 ), 50 seed mass (0.60 and 0.62 g), and 1000 seed mass (12 and 12.4 g) within the moisture content range of 12 to 18% dm. The angle of repose of baobab seeds decreased with an increase in moisture content. The maximum value of 29.18o was obtained at 14% moisture content while a minimum value of 24.42o was obtained at 18% moisture. Moisture content had a significant effect on coefficient of friction of baobab seeds on glass, stainless steel, plywood and rubber. In the same moisture range (12-18%), the static coefficient of friction for baobab seeds ranged from 0-739 to 0-905 on stainless steel, 0-960 to 1-190 on galvanized steel, 0-812 to 1-055 on plywood and 0- 496 to 0-950 on glass. The least coefficient of friction values were recorded on stainless steel and glass which implies that baobab seeds will move with lower resistance on these surfaces in post-harvest handling. On the other hand, the resistance will be higher on plywood and glass. The data obtained will serve as guide for agricultural and food engineers, food processors and technicians involved in design and construction of post-harvest equipment used for separating, cleaning, milling and other production processes, to which baobab seeds are subjected.W pracy zbadano właściwości fizyczne nasion baobabu w celu określenia parametrów urządzeń do ich przetwarzania. Strąki baobabu zostały zebrane w gospodarstwie w miejscowości Ilorin w północno-środkowej Nigerii. Właściwości fizyczne określone w pracy to zawartość wilgoci, masa, wymiary osiowe, wskaźniki kształtu, gęstość rzeczywistą i objętościową, porowatość, kąt usypu i powierzchnię. Wyniki wykazały, że właściwości fizyczne nasion baobabu są stabilne dla wilgotności pomiędzy 12 a 18% suchej masy (sm). W zakresie wilgotności od 12 do 18% sm stwierdzono wzrost masy 100 nasion (g) i średniej geometrycznej średnicy odpowiednio z 0,60 g do 0,62 g i 10,12 do 10,27 mm. Pozostałe zbadane zakresy właściwości fizycznych to: średnia długość (12,22 do 12,63 mm), szerokość (10,10 do 10,28 mm), grubość (8,23 do 8,42 mm), kulistość (81,23 do 82,56 mm), pole powierzchni (319,42 do 332,53 mm2 ), masa 50 nasion (0,60 i 0,62 g) oraz masa 1000 nasion (12 i 12,4 g) w zakresie wilgotności od 12 do 18% sm. Kąt usypu zmniejszał się wraz ze wzrostem wilgotności, maksymalną wartość 29,18o uzyskano przy wilgotności 14%, natomiast minimalną 24,42o przy 18% sm. Wilgotność miała istotny wpływ na współczynnik tarcia nasion baobabu na szkle, stali nierdzewnej, sklejce i gumie. W tym samym zakresie wilgotności 12-18% współczynnik tarcia statycznego dla nasion baobabu wynosił od 0-739 do 0-905 na stali nierdzewnej, 0-960 do 1-190 na stali ocynkowanej, 0-812 do 1-055 na sklejce i 0-496 do 0-950 na szkle. Najmniejsze wartości współczynnika tarcia odnotowano na stali nierdzewnej i szkle. Sugeruje to, że nasiona baobabu będą się przesuwać z mniejszym oporem na powierzchniach z tych materiałów, jeżeli wykorzysta się je do produkcji urządzeń przetwórczych, podczas większy opór wystąpi na sklejce i szkle. Uzyskane dane mogą posłużyć technologom rolnictwa i żywności, zakładom przetwórstwa żywności i konstruktorom maszyn do przetwórstwa baobabu, np. urządzeń do sortowania, czyszczenia, mielenia itp
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