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Rural-urban migration often triggers additional demand for housing and infrastructural development to cater for the growing population in urban areas. Consequently, town planners and urban development authorities need to understand the urban development trend to make sustainable urban planning decisions. Yet, methods to analyse changes and trends in urban spatial development are often complex and require costly data collection. This article thus presents a simplified method to analyse the urban development trend in an area. The method integrates Google Earth (GE) historical imagery (baseline data) and unmanned aerial vehicle (UAV) photogrammetry (recent data) to quantify the changes over time. This approach can be applied to study the urban development trends in low-income countries with budget constraints. The method is discussed under four main headings: (1) background, (2) method details, (3) limitations, and (4) conclusion.â¢Google Earth historical image can be extracted with its associated world file.â¢The population of an area can be estimated by using average household size data and the number of residential buildings in the area.â¢The building height ratio can be used to ascertain if the land is being used parsimoniously.
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The interrelationships between air quality, land cover change, and road networks in the Lagos megacity have not been explored. Globally, there are knowledge gaps in understanding these dynamics, especially using remote sensing data. This study used multi-temporal and multi-spectral Landsat imageries at four epochs (2002, 2013, 2015, and 2020) to evaluate the aerosol optical thickness (AOT) levels in relation to land cover and road networks in the Lagos megacity. A look-up table (LUT) was generated using Py6S, a python-based 6S module, to simulate the AOT using land surface reflectance and top of atmosphere reflectance. A comparative assessment of the method against in situ measurements of particulate matter (PM) at different locations shows a strong positive correlation between the imagery-derived AOT values and the PMs. The AOT concentration across the land cover and road networks showed an increasing trend from 2002 to 2020, which could be explained by urbanization in the megacity. The higher concentration of AOT along the major roads is attributed to the high air pollutants released from vehicles, including home/office generators and industries along the road corridors. The continuous rise in pollutant values requires urgent intervention and mitigation efforts. Remote sensing-based AOT monitoring is a possible solution.
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Contaminantes Atmosféricos , Monitoreo del Ambiente , Monitoreo del Ambiente/métodos , Nigeria , Contaminantes Atmosféricos/análisis , Material Particulado/análisis , Aerosoles/análisisRESUMEN
Urban development will likely continue to increase in suburban areas to cater for the growing human population. In Nigeria, the relevant analysis of these urban developments is not well documented. This article presents spatiotemporal datasets for analysing urban developments in a suburb of Kuje, an Area Council within the Federal Capital Territory of Nigeria. Data from Google Earth (GE) historical imagery of 2005 was used as a baseline for analysis and was compared with a UAV digital orthomosaic of 2019 to quantify urban developments. This data provides useful information on the status of urban development that has taken place in the Kuje suburb over 14 years. The data will be of great importance to town planners and urban development authorities for future planning, and for making informed decisions about urban development issues in the area.
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Weft knitted conductive fabrics can act as excellent textile strain sensors for human motion capture. The loop architecture dictates the overall electrical properties of weft knit strain sensors. Therefore, research into loop architecture is relevant for comprehensively investigating the design space of e-textile sensors. There are three main types of knit stitches, Knitted loop stitch, Miss stitch, and Tuck stitch. Nevertheless, most of the research into weft knit strain sensors has largely focused on fabrics with only knitted loop stitches. Miss and tuck stitches will affect the contact points in the sensor and, consequently, its piezoresistivity. Therefore, this paper investigates the impact of incorporating miss and tuck stitches on the piezoresistivity of a weft knit sensor. Particularly, the electromechanical models of a miss stitch and a tuck stitch in a weft knit sensor are proposed. These models were used in order to develop loop configurations of sensors that consist of various percentages of miss or tuck stitches. Subsequently, the developed loop configurations were simulated while using LTspice and MATLAB software; and, verified experimentally through a tensile test. The experimental results closely agree with the simulated results. Furthermore, the results reveal that increases in the percentage of tuck or miss stitches in weft knit sensor decrease the initial and average resistance of the sensor. In addition, it was observed that, although the piezoresistivity of a sensor with tuck or miss stitches is best characterised as a quadratic polynomial, increases in the percentage of tuck stitches in the sensor increase the linearity of the sensor's piezoresistivity.
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Ackee (Blighia sapida) is a commonly eaten fruit that is indigenous to West Africa and Jamaica. Ackee poisoning in young children have been reported in parts of Nigeria due to consumption of the unripe fruits. This study was designed to identify potential mechanisms of acute and sub-acute toxicity of unripe B. sapida fruit extract (BSE). Acute toxic effect was investigated in mice of either sex administered BSE 2000 mg/kg. The sub-acute toxicity effects were investigated in mice of either sex that received 28 days repeated administration of BSE (100 and 500 mg/kg, p.o.). Locomotor activity and memory performance were measured as well as seizure vulnerability in PTZ-induced model. Liver enzymes were assessed in the serum. Acetylcholinesterase, oxidative stress parameters and histopathological changes were assessed in the brain and liver tissues. Signs and symptoms of toxicity such as urination, tremor, depressed locomotion and death were observed in acute toxicity test. Sub-acute dosing caused significant impairment in locomotor activity and memory performance in mice. Seizure threshold was shortened in BSE-treated compared to control mice. Brain acetylcholinesterase activity was significantly increased. Alkaline phosphatase (ALP) was significantly elevated in mice that received BSE (500 mg/kg). Furthermore, BSE caused significant increase in oxidative stress expressed in nitrite, malondialdehyde, reduced glutathione and catalase in the brain and liver tissues. Histological staining revealed neuronal damage of brain hippocampus and hepatocellular swelling and necrosis. Blighia sapida unripe fruit extract increased susceptibility to seizure and impaired locomotor and memory function. The biochemical and histopathological findings revealed potential toxicity mechanisms related to neurotoxicity and hepatotoxicity.
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Background The use of plants for the treatment and prevention of diseases in man and his animals has led to a renewed scientific interest in the use of medicinal plants for therapeutic purposes. The nephroprotective properties of methanol stem bark extract of Abrus precatorius against gentamicin-induced renal damage in rats was evaluated in this study. Methods Thirty male Wistar rats were divided into five equal groups. Group A was the negative control group while B was the positive control group which received gentamicin 100 mg/kg intra-peritoneally for 6 days. Group C were pretreated with 100 mg/kg extract for the 3 days and then concurrently with gentamicin 100 mg/kg for 3 days and group D were pretreated with 200 mg/kg extract for 3 days and then concurrently with gentamicin 100 mg/kg for 3 days. Group E received gentamicin intraperitoneally for 6 days followed by administration of 200 mg/kg of the extract for 3 days. Blood samples, kidneys and kidney homogenates were collected for haematological, biochemical, histopathological and immunohistochemical analysis. Results The results showed that no significant haematological changes were noted. The groups treated with extract exhibited significant increase in body weight gain. While group B significantly exhibited focal areas of inflammation, fatty degeneration, congestion of vessels, tubular necrosis and glomerular atrophy, the lesions were mild with the treated groups. Treated groups exhibited a dose dependent significant decrease in serum creatinine, urea, XO, NO and Myeloperoxidase, AOPP, Protein carbonyl, H2O2 generated and MDA levels when compared with group B. There were significant dose dependent improvements in SOD, GST, GSH, Protein thiol, and non-protein thiol levels in the treated groups when compared with group B. In immunohistochemistry, Group B exhibited over expression of CRP and NF-κB levels, and marked reduction in expression of Bcl-2 while the reverse was seen in the groups treated with methanol extracts of Abrus precatorius. Conclusion The methanol extract of Abrus precatorius plays a vital role against gentamicin induced renal damage by reducing levels of renal markers of oxidative stress, inflammation and apoptosis, enhancing enzymatic and non enzymatic renal antioxidant system, alongside an increase in Bcl-2 and a decrease in NF-κB and CRP expressions.