Ethiopian Journal of Science and Technology

Effect of castor leaves supplemented with seed flours of soybean, cowpea and amaranthus on larval and cocoon parameters of eri-silkworms (Samia cynthia ricini)

Beshada Taye — 2024-11-08

The growth, development, and silk yield of silkworms are highly affected by the quality of the leaves used as feed. In the present investigation, eri silkworms were fed flour supplements made from soybean (Glycine sp.), cowpea (Vigna sp.), and Amaranthus (Amaranthus sp.) seeds at concentration levels of 45 g/kg, 30 g/kg, and 15 g/kg of castor leaf, respectively. A control group was included with castor leaves and no supplementation. The experiment, comprising ten treatments, was laid out in a completely randomized design (CRD) with five replications at the Melkassa Agricultural Research Center (MARC) in the East Shewa Zone of Oromia Regional State, Ethiopia. The treatments were evaluated for their effects on important larval and cocoon parameters of eri silkworms (Samia cynthia ricini B.) using a white plain Eri silkworm breed known as Eri-3.4. Data analysis was conducted using SAS software at a 5% probability level. The treatment combinations showed significant differences among themselves, and the addition of leaf supplements in powder form improved various larval and cocoon parameters, including larval weight, effective rate of rearing, cocoon weight, pupal weight, shell weight, and shell ratio. Among the treatments, soybean at a rate of 45 g/kg of castor leaf and 30 g/kg of castor leaf, cowpea at 45 g/kg of castor leaf, and Amaranthus at 45 g/kg of castor leaf were found to be superior, yielding better results in terms of larval and cocoon parameters. Therefore, it can be concluded that applying powders made from the seeds of soybean, cowpea, and Amaranthus on castor leaves improves eri silkworm parameters and can be considered as basic inputs for supplementary feed in future silkworm rearing.

Prevalence and associated risk factors of bovine schistosomiasis in Dembecha district, North West Ethiopia

Bezaneh Ayalew — 2024-11-08

A cross-sectional study design using a cluster sampling method was employed to estimate the prevalence of bovine schistosomiasis, identify potential risk factors, and reveal the distribution of snails in moist environments in the Dembecha district of Ethiopia. Fecal examinations for parasitic eggs and visual observations of snail distributions were conducted in four kebeles (the lowest administrative unit in Ethiopia) within the study district. The study investigated potential risk factors such as age, sex, body condition, management system, and grazing area of cattle. The results indicated that the prevalence of schistosomiasis was 16.4% (63 out of 384), with significantly higher rates in cattle with poor body condition (p = 0.003). Wad and Yetsed kebeles exhibited relatively high snail infestations compared to Godber and Yemehal. In conclusion, schistosomiasis is prevalent in the Dembecha district, necessitating further research to identify the species of the parasite and its snail intermediate host.

Analysis of a mathematical model of transmission dynamics of HIV/AIDS with saturated incidence rate

Olopade I. Adesola — 2024-11-08

In this study, a mathematical model for the HIV/AIDS epidemic is developed and analyzed to gain insight into the current and past states of HIV/AIDS and other epidemiological features that cause the progression from HIV to full-blown AIDS. The existence and uniqueness of the model show that the solutions exist and are unique. The basic reproduction number is the average number of new secondary infections generated by a single infected individual during the infectious period, which is established using the next-generation matrix method. The analysis shows that the disease-free equilibrium is locally asymptotically stable whenever the threshold quantity is less than unity, i.e., R₀ < 1, and is otherwise epidemic. The sensitivity of parameters with respect to the basic reproduction number shows that parameters with a positive index will increase the basic reproduction number; for example, the effective contact rate must not exceed 0.39 to avoid an endemic stage. Numerical analysis of the work shows the importance of the memory term; it also indicates that control measures targeted at the history of any disease and immunity boosts should be adopted to prevent HIV from leading to full-blown AIDS.

Essential oil and antioxidant activity of the aerial parts of coriander (Coriandrum sativum L.) cultivated in Ethiopia

Mekides Assefa — 2024-11-08

Coriander (Coriandrum sativum L.) is an annual herbaceous plant which is used as spice. It is widely cultivated throughout the world for its essential oils. The percent composition of commercial essential oils is highly variable due to the effect of geographical origin. In the present investigation, the chemical constituents of the essential oils obtained from the aerial parts of the plant collected from three different areas of Ethiopia were determined by gas chromatography-mass spectrometry. The number of compounds identified in the essential oils of the plants from Jimma was 47, from Wolaita Sodo 21, and from Sululta 19. The major components of the essential oils were found to be decanal and (E)-2-decenal. The methanol extract of coriander aerial parts exhibited DPPH anti-oxidant activities in the range 91.1-92.3% at 500 µg/mL. Therefore, coriander aerial parts can safely be used for food flavoring and food preservation.

Application of social media tools for project management in Rwanda

Oluwaseun Sunday Dosumu — 2024-09-17

The construction industry, both in developed and developing countries, has increasingly adopted social media tools to improve project management. However, there is a notable lack of documentation regarding the awareness, adoption, and application of these tools in the construction sector of developing countries, particularly in Rwanda. This study aims to investigate the level of awareness, adoption, and application of social media tools in construction projects. To achieve this, we employed a survey research design, administering closed-ended questionnaires to construction professionals in Rwanda, supplemented by unstructured interviews to clarify responses as needed. The findings indicate that respondents are generally aware of and have adopted social media tools for construction project management. Furthermore, a direct correlation exists between the level of awareness and the level of adoption of these tools. However, significant differences were observed between consultants and contractors concerning their awareness and adoption rates. The primary applications of social media tools identified in the study include information exchange and storage, organizational cooperation, marketing, knowledge sharing, employment opportunities, networking, and the creation of project groups. Based on these findings, the study recommends that professional bodies enhance awareness by organizing conferences, seminars, and meetings to discuss the applications and benefits of social media tools in construction projects. Additionally, project consultants should be encouraged to recommend appropriate social media tools to project bidders. Governments and policymakers should consider incentivizing effective users of these tools within the construction sector. Lastly, academics should be encouraged to devote more research efforts to exploring the specific applications, benefits, and challenges of adopting social media tools in the construction industry.