 Subjects -> SCIENCES: COMPREHENSIVE WORKS (Total: 374 journals)
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- Investigation of a Lodged Bullet inside a Human Brain using Computed
Tomographic (CT) Imaging
Authors: Getasew Admasu Wubetu
Pages: 38 - 48
Abstract: We reported the location of a lodged bullet inside a human brain from the 2D and 3D images using Computed Tomography (CT). It is based on the scanning of the hard and the soft tissues of the brain as well as a bullet by X-ray photons on the circular 3600 CCD detectors. The absorption on the target brain and the bullet had significant differences in the measured current (mA) and the mapped Hounsfield Unit (HU) as a function of the number of slices. The 2D and the reconstructed 3D images displayed the brain soft tissue, which was dark with low HU compared to the white in the bullet part with a higher HU. The attenuation coefficients of a bullet with Copper (Cu) and the skull of the brain with Calcium (Ca) were higher than that of the brain soft tissues with Hydrogen (H) and Oxygen (O). A typical example is the observation of the image at the center of the slices displayed brighter at 3071 HU. 3D structures of brain images were generated and visualized in different viewing positions. The measured value for a lodged bullet was 11.28 cm away from its entry (Frontal), 7.92 cm from the back, and 6.96 cm deep, down from the upper part of the brain. Based on our analysis, the bullet is located in the left hemisphere, which is part of the hypothalamus and parity.
PubDate: 2023-01-30
DOI: 10.20372/ejssdastu:v10.i1.2023.531
Issue No: Vol. 10, No. 1 (2023)
- Assessment of Soil Acidity and Determination of Lime Requirement under
Different Land Uses in Gumer District, Southern Ethiopia
Authors: Achalu Chimdi YARIMO, Aliyu Nesru Nesru, Wondwosen Tena Tena
Pages: 49 - 60
Abstract: Abstract: The study was initiated to assess the level of soil acidity and lime requirement of four types of land uses (forest lands, grazing lands, cultivated lands, and Eucalyptus tree plantation) and in replications from 0-20 cm soil depth. Lime requirement was evaluated by exchangeable acidity and buffer solution methods. The data were analyzed by SAS software, version 9.1. The study revealed that soils of cultivated and Eucalyptus lands were very strongly acidic with mean of pH 4.8 and 5.0, whereas soils of grazing lands were strongly acidic with pH 5.5 and forest lands were moderately acidic with pH 5.7and 5.6 in both kebeles, respectively. Meaningfully higher pH, OM, TN, CEC, exchangeable Ca2+, and Mg2+ were noted under forest lands as compared to the remaining land uses. However, meaningfully lower exchangeable acidity (EA) (1.06) and percentage acid saturation (PAS) (5.18) were obtained in the forest lands than in the other land uses. Significantly higher available P (2.54) was noted in the grazing land, followed by natural forest (1.77) land for Berchernamocheya kebele, and higher available P was recorded under forest (2.50), followed by grazing land (2.37) for Badnayegor kebele. Significantly higher exchangeable K+ (1.29) and Na+ (0.63) were observed in grazing land for Badnayegor and Berchernamocheya Kebeles, respectively. The results of the lime requirement revealed that using the SMP buffer solution method recorded 4.1-11.3 t/ha while using the exchangeable acidity method recorded 1.3-6.7 t/ha across the land uses for both kebeles. Based on lime requirement determination methods, the amount of lime required highly varies among the land uses. The investigation showed that soil acidification is a serious problem in the study areas. Thus, integrated land management needs to be practiced to overcome the problem of soil acidification and achieve sustainable agricultural production.
PubDate: 2023-02-02
DOI: 10.20372/ejssdastu:v10.i1.2023.512
Issue No: Vol. 10, No. 1 (2023)
- Determinants of Rural-Urban Migrants’ Employment Choice in Urban Labor
Market: Study from Cities in Central Oromia, Ethiopia
Authors: Oumer Beriso
Pages: 61 - 74
Abstract: Abstract This study investigates the determinants of rural-urban migrants’ employment choices in the urban labor market in central Oromia cities, Ethiopia. The study used a cross-sectional data obtained from rural-to-urban youth migrants, and it estimated multinomial logistic regression to analyze the data. For this purpose, after the urban labor market had been categorized into five urban employment segments, a multinomial logit model was employed to identify factors determining migrants’ job choices from these employment segments. The finding reveals that a migrant’s sex and his/her parent’s annual income have positive significant effects on all employment segments. Migrant’s marriage, information deficiency on job availability, being from small urban area, and father’s occupation have significant positive effects on self-employment, while lack of a city’s identification card for the immigrant and dispute in the city have significant negative effects on the segment. Migrant’s duration of living in cities, information deficiency on job availability, and father’s education and occupation have significant positive effects on informal private-employment. On the contrary, marriage, household size, and lack of identification card have negative impacts on the segment. A migrant’s age, preparatory schooling level, university education, access to registration, and advisory services in the city have significant positive effects on both (private and public) formal employments. The paper has made conclusions and drawn policy implications for possible interventions to urban labor market constraints.
PubDate: 2023-02-20
DOI: 10.20372/ejssdastu:v10.i1.2023.546
Issue No: Vol. 10, No. 1 (2023)
- Characterization of Home-Made and Industrially Produced Niger Seed Oils by
Fluorescence Spectroscopy
Authors: Alemu kebede wordefa
Pages: 1 - 6
Abstract: Home-made and industrially produced Niger seed oils were characterized by a fluorescence spectrometer to analyze the impact of the industrial process on the physical and chemical properties of the oil. The excitation wavelength was varied from 350 nm–380 nm with an incremental step of 10 nm, and the slit width was kept at 5 nm. Experimental results indicated that the major components in oil samples (home-made, unrefined, and refined industrially produced) were Vitamin E, Poly-unsaturated fatty acid, and Chlorophyll. Emission spectra recorded in the range of band between 400 nm – 500 nm were related to Poly-unsaturated fatty acids; those spectra recorded in the range of band between 500 nm-550 nm with a peak around 548 nm belong to vitamins E; and the band of emission wavelength between 650 nm – 725 nm were due to Chlorophyll. It was also observed that the refined oil had a very small vitamin E peak. This could be associated with the heating process of refining, as vitamin E is heat-unstable. Moreover, the emergence of new peaks in the spectra of the refined oil between 400 nm – 450 nm was due to fat-soluble vitamins and lipids that emerge as a result of oxidative reaction during the heating process. Moreover, an increase in excitation wavelength also resulted in a blue shift of the emission spectra. This was because of the presence of more than one fluorophore (luminophore) in the molecule. The calculated quantum yield of the fluorescence of the sample/un-purified was 0.01042, which is a 10% reduction compared to the purified oil. An increase in pH values also resulted in a decrease in fluorescence intensity and vice-versa.
PubDate: 2022-12-01
DOI: 10.20372/ejssdastu:v10.i1.2023.509
Issue No: Vol. 10, No. 1 (2022)
- Comparison of biogas productivity of calabash waste mixed in selected
ratios with sheep and donkey dungs
Authors: Moges Admasie, Tewabech Temesgen, Fasika Kebede
Pages: 7 - 19
Abstract: Anaerobic digestion process is one of the non-thermal technologies of energy recovery to meet the ever-growing energy demand of rural areas in developing countries, particularly Ethiopia, in a green way. The aim of the present study was to investigate the effectiveness and performance characteristics of anaerobic digestion of calabash waste mixed in selected ratios with donkey and sheep dung for biogas production. Production of biogas from calabash waste, mixed with donkey and sheep dung in ratios 1:1, 2:1, 3:1, and 4:1 by mass, was investigated in a 45 L plastic container using a retention period of 20 days and within the mesophilic temperature range. The average biogas yield was significantly (P≤ 0.05) influenced by the different mixing ratios of calabash waste with dung. The composition of gas generated from each ratio ranged (from 67.41-63.81)% CH4, (33.00-26.01)%, CO2, (1.06-0.40)% CO, (3.00-0.07)% H2O, (0.06-0.02)% NH4,(0.90-0.05)% N, (0.72-0.02)% H, (0.98-0.09) % O2, and (0.006-0.001) % H2S. The average biogas yield was 13.5, 11.6, 10.7, and 7.8L respectively for 1:1, 2:1, 3:1, and 4:1 mixing ratios when calabash waste was mixed with sheep dung. On mixing calabash waste with donkey dung, the average biogas yield increased to 16.2, 15.5, 12.6, and 9.8L respectively for 1:1, 2:1, 3:1, and 4:1 mixing ratios. The results show that mixing both dungs with calabash waste in a ratio of 1:1 by mass-produced the highest biogas volumes, and higher in donkey dung. The reason behind this is that higher mixing ratios meant a higher quantity of waste in the mixture which also implied increased lignin content, and this made digestion activities more difficult for the microbes. Reduction in digestion activities of the methanogen bacteria resulted in lower biogas yield. The result of the present study has shown that anaerobic digestion from calabash waste, mixed with donkey and sheep dung in ratios 1:1, 2:1, 3:1, and 4:1 by mass can form a renewable energy that is comfortable and environmentally friendly. This energy production process is found to be an easy way of replacing fossil fuels.
PubDate: 2022-12-22
DOI: 10.20372/ejssdastu:v10.i1.2023.458
Issue No: Vol. 10, No. 1 (2022)
- Facile Ambient Air Quality Indicator Monitoring Technique for Estimating
Cadmium and Lead Content in Atmospheric Dust.
Authors: Okponmwense Moses, Aimudogbe Benjamin Ehinomen
Pages: 20 - 27
Abstract: Dust emitted into the air through human activities reduces air quality because it comes along with its deleterious constituents. This study aims to monitor the ambient air quality via the estimation of cadmium and lead concentration in the dust-polluted atmospheric environment using vegetable leaves. Leaves of pumpkin (Telfairia Occidentalis) and green (Amaranthus hybridus) vegetables obtained from Oba, Ekiosa, New Benin, and Ikpoba-Hill markets in Edo State, Nigeria, were washed with de-ionized water, spread, and exposed on tables placed at ten different points, 10 meters apart near the roadside outside and inside each market from 8:00 am to 6:00 pm every day (Monday - Friday) for three months (from November to March). The cadmium and lead pollutants in the dust deposit were analyzed using atomic absorption spectrophotometer after wet digestion of the different collectors. The study revealed that there was no cadmium content in the dust deposited on the vegetable leaves exposed inside each market. Atmospheric dust deposited on the vegetable leaves outside each market had cadmium content up to the tune of ≤0.01mg/kg. The study also revealed that the atmospheric dust inside and outside each market contained lead content. The lead content in the dust deposit obtained from outside each market ranged from 0.03-1.04 mg/kg, and the lead content in the atmospheric dust deposit obtained from inside each market ranged from 0.02-0.69 mg/kg. The air quality index (AQI) prediction for cadmium inside and outside the market atmosphere was very good (very clean). However, for the lead contaminant, the AQI rating outside and inside the market ranged from moderate (fairly clean) to very poor (severely polluted). Ekiosa market was very poor (severely polluted) and the Ikpoba-Hill market was moderate (fairly clean) due to lead contaminants in dust deposited due to human activities and heavy vehicular traffic.
PubDate: 2022-12-23
DOI: 10.20372/ejssdastu:v10.i1.2023.540
Issue No: Vol. 10, No. 1 (2022)
- Soil phosphorus adsorption characteristics and kinetics under different
land use types: The case of Dire Inchine District, West Showa Zone,
Oromia, Ethiopia
Authors: Achalu Chimdi YARIMO
Pages: 28 - 37
Abstract: Soil phosphorus is an essential plant nutrient, and its insufficiency severely limits crop yields. However, its adsorption study plays a vital role in devising appropriate soil phosphorus, “P”, management practices for its use proficiency. This study was initiated to evaluate phosphorous adsorption characteristics and kinetics of soil of three different land uses. A representative topsoil samples (0-20 cm) depth from the forest, grazing, and cultivated lands were collected and weighed 1g of composited soil samples were equilibrated in 20 ml of 0.01 M CaCl2 solution containing KH2PO4 at rates of( 0, 5, 25, 100, 150 and 250) mg P L-1 for assessment of Langmuir adsorption isotherm using batch type experiment. Then, the equilibration time was deduced from the kinetic experiment and fixed at 5 hours. The textural class of soils of forest land was clayey loam, whereas that of grazing and cultivated lands was clayey. Soil pH values under the three land uses were found to be strongly acidic. The experimental soils differed considerably in sorption characteristics under the three land uses. The highest mean value of the product of biding energy and sorption maximum (Kqmax) was recorded in the soil of cultivated land (1.08 Lmg-1) followed by forest land soil (0.7313 Lmg-1), while the lowest was recorded for the soil of grazing land (0.672 Lmg-1), indicating considerable variation soil phosphorus adsorption characteristics under three land-uses. The value of the regression equation (R2) indicated that higher values (R2 > 0.9864) have better soil binding strength than the others. Thus, the good fitness of the model was ascertained by witnessing the R2 values. The kinetic data showed that the values of concentration of soil “P” adsorbed (qe) under the three land uses were closer and the R2 values were comparably lower and almost analogous for the pseudo 1st order kinetic model than the pseudo 2nd order model. Soil “P” sorption kinetics was fast in the first 120 minutes and then showed no change with the increase of the contact time.
PubDate: 2022-12-23
DOI: 10.20372/ejssdastu:v10.i1.2023.526
Issue No: Vol. 10, No. 1 (2022)
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