SINET - Ethiopian Journal of Science

DLLME coupled with HPLC-DAD for enrichment of pesticide residues in environmental sediment and soil samples

Yosef Alemayehu , Teshome Tolcha , Negussie Megersa — Thu, 23 Feb 2023 00:00:00 +0000

Sample pre-treatment during determination of pesticides in sediment and soil is difficult due to matrix effects. For this reason, a low density dispersive liquid-liquid microextraction (ld-dllme) was developed for the determination of carbaryl, cynazine, atrazine, and propazine. The experimental parameters that could potentially influence performances of the developed analytical technique including the extraction solvent type and volume, disperser solvent type and volume, extraction and centrifugation time, centrifugation speed, salt concentration, and pH were optimized. The optimum experimental values were found to be 50 mL 1-octanol, 0.6 mL acetonitrile, 5 min extraction time, centrifugation at 3500 rpm for 3 min, 10% NaCl and pH 5. At the optimum conditions, the methods offer good linearity (R² = 0.998–0.999) for the concentration ranges of 30-800 µg/kg; the detection limit (lod) ranging from 9-24 µg/kg; precision <5.3% rsd, and reproducibility 0.5-5.2% rsd. The accuracy of the method, determined in terms of recovery was found to vary from 74.5-109.7%. Therefore, the developed analytical method could be used for the determination of trace level of pesticides residues in sediment and agricultural soil samples.

Factors affecting cloud-based enterprise resource planning software adoption in Ethiopia

Biniyam Fekadu , Lemma Lessa — Thu, 23 Feb 2023 00:00:00 +0000

Enterprise Resource Planning (erp) are integrated software solutions that transform organizations’ internal processes, provide collaboration with partners, external applications and information systems. Extant literature reveals that organizations are showing interest to transit from an on-premise erp to the new cloud-based erp solutions due to their extra benefits. There are few recent initiatives in Ethiopia to adopt cloud-based erp but challenges faced in the course of the adoption are not explored. Using the technology-organization-environment, diffusion of innovation, and the model of innovation resistance frameworks as lenses, this research aims at identifying factors contributing to the adoption of cloud-based erp in the Ethiopian context. A quantitative approach is adopted and survey was conducted using a self-administered online questionnaire using Google’s online form to gather data from employees of Ethiopian Shipping and Logistics Services Enterprise. Out of 295 questionnaires distributed, 152 valid questionnaires were collected and considered for the data analysis. The proposed model was tested using a partial least square with the help of the Smart pls software. The proposed model explained 58.5 % of the variance in cloud-based ERP adoption factors. The empirical analysis indicated that Relative advantage, Trust, IT Skill, and External pressure had a significant influence on the adoption of cloud-based erp in Ethiopia whereas Organizational Culture, Observability, and Trialability had no significant impact on the adoption of cloud erp service. The study provides a comprehensive understanding of the factors which affect the adoption of cloud-based erp technology in Ethiopia.

Multiclass classification of Ethiopian coffee bean using deep learning

Getabalew Amtate , Dereje Teferi — Thu, 23 Feb 2023 00:00:00 +0000

Ethiopia is the homeland of Coffee Arabica. Coffee is the major export commodity and a high-income source of foreign currency for the country. In addition to this, coffee has a great role in social interaction between people and is also a source of income for the coffee-producing farmers. Several types of coffee beans grow in Ethiopia. These beans are distinct from each other in terms of quality, color, shape etc. based on their geographical origins. Classification of these coffee beans are based on growing origin, altitude, bean shape and color, preparation method and others. However, the quality of the coffee beans is determined by visual inspection, which is subjective, laborious, and prone to error. This creates the necessity for the development of an automatic method that is precise, non-destructive and objective. Thus, this research aims to develop a model that classifies coffee beans of six different origins of Ethiopia (Jimma, Limmu, Nekemte, Yirgacheffe, Bebeka, and Sidama) in to nine classes. The dataset for this research is collected from the Ethiopian Coffee Quality Inspection and Auction Center (ecqiac). This research followed design science research (dsr) to investigate the problem. Image processing and the state-of-the-art deep-learning techniques were employed to automatically classify coffee bean images into nine different classes grown in six different regions of Ethiopia. A total of 8646 coffee bean images were collected and 1190 images were added using augmentation to make the total dataset 9836. The model is trained and tested by tuning the hyper-parameters of the cnn algorithm. When 80% of the dataset is used for training, 10% for validation, and the remaining 10% for testing, the proposed model achieved a 99.89% overall classification accuracy with 0.92% generalization log-loss. In conclusion, the result of this research shows that deep learning is an effective technique for classification of Ethiopian coffee beans and can be implemented in the coffee industry.

Household food insecurity and food safety knowledge, attitude, and practice of mothers with outpatient under-five children at Cure Hospital, Addis Ababa

Hiwot Disassa , Mogessie Ashenafi — Thu, 23 Feb 2023 00:00:00 +0000

Foodborne illnesses result in life-threatening conditions among vulnerable members of households. Proper knowledge, attitude and practices in food safety issues are important to curb the damage caused by these illnesses at household level. This study examined the food insecurity experiences and food safety knowledge, attitude, and practice (kap) of mothers having outpatient children in Cure Hospital, Addis Ababa, Ethiopia. A sample size of 210 randomly selected mothers was considered for this study. A cross-sectional study was carried out using semi-structured questionnaire to collect data on food insecurity experiences and food safety knowledge, attitude and practice of respondents. Data was analyzed using descriptive statistics. Most respondents were married (68%), had primary or secondary level education (62%), had one or two under-five children (71%), and 52% had monthly income between etb 500 and 2500. Between 70% and 80% of the respondents experienced anxiety or uncertainty of not having enough food for household members or reduced quality or quantity of food they ate in the previous thirty days. Around 58% experienced hunger during the same period. The knowledge of mothers in food safety (food handling, personal hygiene and water sanitation) was generally poor (<60%). The level of positive attitudes of mothers towards food safety was also poor (<60%). Appropriate practices, particularly in food handling and personal hygiene were also very poor. As foodborne illnesses can be fatal to vulnerable members of a household, a thorough training to mothers in food safety issues is recommended.

Phytobeneficial traits of Rhizobacteria isolated from degraded soil and evaluate their effect in augmentation of Acacia (Acacia abyssinica Hochst. Ex Benth) seeds germination

Thu, 23 Feb 2023 00:00:00 +0000

Microbes are an integral component of the soil ecosystem but degraded soil has few native beneficial microbes. This necessitates the characterization of phytobeneficial bacteria having numerous features. The study was initiated to evaluate rhizobacteria enhancing Acacia (Acacia abyssinica) seed germination. Isolates were selected based primarily on phosphate solubilization activity and other traits hydrogen cyanide (hcn), phytohormone, hydrolytic enzyme, siderophore, ammonia. Among isolates, 45% each was categorized as high and medium phosphate solubilizers and the amount was found to range from 195 to 373 µg/mL. The highest solubilization index (SI) 7 was recorded for Acinetobacter BS-27 and 6 for Pantoea BS-38. The maximum P and iaa were produced by Pseudomonas FB-49 (373 and 659.07µg/mL), respectively. Isolates with multiple traits were chosen for seed germination. Accordingly, Agrobacterium RS-79 and Pseudomonas BS-26 showed 100% activity. A 100% seed germination and vigor index (343.33 and 306.67) were observed in Pseudomonas BS-26 and FB-49. Degraded soil is considered a source for phosphate solubilizing and other beneficial bacteria with many traits to be used for seed germination assay.

Effect of elevated fry rearing temperature on survival rate, growth performance, and sex ratio of three Oreochromis niloticus populations of Ethiopian Rift Valley Lakes

Megerssa Endebu , Abebe Getahun, Misikire Tessema — Thu, 23 Feb 2023 00:00:00 +0000

Sex-reversal in Oreochromis niloticus is used to produce mono-sex males which are desired in aquaculture for better growth performances and population control. The present study was aimed at studying the effect of elevated fry rearing temperature on survival, sex ratios, and growth performances of O. niloticus populations of Lakes Chamo, Koka, and Ziway. Fries from five separate brood pairs of each population were either treated (T) in elevated fry rearing temperature of 36 ± 1°C or kept at room temperature of 24 ± 1°C as control (C) groups for 10 days (phase-I) and then grown in outdoor ponds for six months (phase-II). Survival rates in T groups (74.0 to 91.7%) were lower than that of C groups (83.3 to 97.0%) in all the three populations in phase-I but not in phase-II. Chamo population was better in survival rate (88.4% and 95.4% in Phase-I, and 95.4% and 95.3% in phase-II) than Koka population (85.8% and 91.3% in Phase-I, and 93.9% and 93.5% in phase-II) and Ziway population (80.2% and 88.6% in Phase-I and 90.2% and 91.9% in phase-II) both in T and C groups respectively. The Chamo population also attained significantly (p<0.05) higher mean final weight of 31.58 ± 6.78 g and 24.26 ± 6.67 g in T and C groups respectively, followed by that of Koka population with 21.70 ± 5.10 g and 18.83 ± 4.16 g while Ziway population with mean final weight of 17.49 ± 4.60 g and 16.81 ± 4.15 g was the least both in T and C groups. The overall sex ratios in T groups were skewed towards male but balanced in all C groups of each population. Better growth was achieved only in T groups with higher male ratio than their corresponding C groups. The number of sensitive brooding pairs and the overall male ratio in T groups were higher in the Koka population (40%, 61.68%) than in Ziway (20%, 56.78%) and Chamo (20%, 56.39%) populations respectively. However, the sensitivity of sex reversal to elevated fry rearing temperature was wide between individuals within each population than across the three populations. Hence, sensitive individuals can be selected from the populations and their degree of sensitivity can be improved through continuous selection of progenies from temperature-sensitive parents.

Population status of the Critically Endangered African White-Backed Vultures (Gyps africanus) in and around Wolkite town, Southwestern Ethiopia

Beselam Shiferaw, Afework Bekele , Bezawork Afework — Thu, 23 Feb 2023 00:00:00 +0000

African white-backed vultures (Gyps africanus) are critically endangered bird species which are commonly found in areas where rubbish food sources and roosting and/or nesting sites are available. This study assessed the population size and threats of the African white-backed vultures in Wolkite town abattoir and the surrounding dumping site from April 2019 to March 2021. A total count method was employed to assess the population size of the species and analyzed using descriptive statistics. A questionnaire consisting semi-structured open-ended questions was used to study the attitude and perception of the local community. During the study period, 192 field visits were conducted to count the population size of African white-backed vultures. Individual African white-backed vultures were counted in the abattoir and dumping sites. About 472 individuals (36%) were counted in the dumping site (Mean ± SD: 20±7.4; Range: 8-29) and 839 individuals (64%) were counted in the abattoir (Mean ± SD: 34±8; Range: 22-47). The age category in the dumping site constituted 269 adults and 203 sub-adults with a statistically significant difference (x²= 8.14, df =1, p< 0.05) between adults and sub-adult age groups. In the abattoir, 319 of the population were adults and 520 were sub-adults, a significant difference (x²= 48.2, df =1, p< 0.05) in the age groups in the area. Threats such as human disturbance and competition for food and roosting with domestic and wild animals were observed during the study period.

Obsidian in Ethiopia: a Geoarchaeological perspective

Agazi Negash — Thu, 23 Feb 2023 00:00:00 +0000

In Ethiopia, obsidian is mainly found in the Afar Depression and the Main Ethiopian Rift. The compositional and petrological features of these obsidians vary. Some volcanic centers show that varying volcanic eruptions from a single center may not necessarily imply variable chemistry. Obsidian has been dated using K/Ar, Ar/Ar, and fission track methods to determine the time of eruption but there are also a few dates on artifacts by hydration dating to establish the time of tool manufacture. Many of the geological sources were utilized by prehistoric populations beginning at least since the Early Stone Age but obsidian became commonly used during the Middle Stone Age. Obsidian based stone tool use for scraping in Ethiopia persisted until recent times.