Ethiopian Journal of Natural and Computational Sciences

ON (m, n)−ABSORBING IDEALS IN AN ADL

2024-11-16T17:37:02+00:00

This paper explores the concept of (m, n)-absorbing ideals within an Almost Distributive Lattice (ADL). It also introduces and examines the notion of weakly (m, n)-absorbing ideals, a more generalized form of (m, n)- absorbing ideals. The primary focus is on establishing the relationships between (m, n)-absorbing ideals (and weakly (m, n)-absorbing ideals) and their counterparts, (m, n)-absorbing prime ideals (and weakly (m, n)-absorbing prime ideals), in an ADL. Additionally, the paper investigates the properties of homomorphic images and inverse images of (m, n)-absorbing ideals, demonstrating that these images retain the structure of (m, n)-absorbing ideals.

The Association of MECA Gene Polymorphism and Drug Resistance Pattern of Methicillin-Resistant Staphylococcus Aureus Isolated from Keha and Shinta Rivers of Gondar Town, Northwest Ethiopia

2024-12-24T16:18:24+00:00

Associated with nosocomial and community-acquired infections, Staphylococcus aureus is a potentially hazardous human bacterium that is alarmingly developing drug resistance. The current study's objective was to assess the association of mecA gene polymorphism and drug resistance pattern of Methicillin-resistant Staphylococcus aureus isolated from Keha and Shinta rivers of Gondar town, Northwest Ethiopia. A purposive sampling technique was used to collect 10 water samples from different sites of the two rivers. Isolation of S. aureus was conducted following standard morphological and biochemical method and subjected to susceptibility testing to 8 antibiotics. Methicillin-resistant Staphylococcus aureus (MRSA) was detected by using the standard PCR method using specific pair of primers. The genomic DNA of the isolates was isolated using a DNA Extraction Kit (GenElutetm., USA). Amplification of mecA gene was done by PCR using a specific primer for the mecA gene. The PCR products were visualized using agarose gelelectrophoresis with 1.5% gel. The results indicated that four (66.7%) Methicillin-Resistant Staphylococcus aureus isolates showed to have 499 bp band size of mecA gene. S. aureus showed a wide range of resistances, with the highest levels observed for ampicillin (100%), penicillin, chloramphenicol, erythromycin, and tetracycline (66.7%). Instead, S. aureus had variable sensitivity to gentamycin (100%) and ciprofloxacin (100%) as well as vancomycin (66.7%). Four (4/6, 66.7 %) S. aureus isolates showed multiple antibiotic-resistant patterns (resistant to four or more antibiotics). The result of this finding concluded that S. aureus isolates with mecA gene developed more resistant to many antibiotics than with mecA negativeisolates. In addition, the present study confirmed that the treated wastewater mixed with the two rivers are potential sources of S. aureus and Methicillin-Resistant Staphylococcus aureus infections, this might be due to the poor wastewater treatment methods followed by several point sources in the study area. In conclusion, this study's findings suggest that the Keha and Shinta Rivers in Gondar Town may be potential receptacles for MRSA, which is capable of infecting both exposed humans and animals.

Fatty Acid Profiles of White Sesame Seeds from the Different Cultivation Areas of Ethiopia

2024-12-24T17:12:50+00:00

Sesame is the second important export commodity of Ethiopia after coffee. The white sesame seeds (Sesamum indicum L.) from the main production areas of Ethiopia have not been studied comprehensibly for their chemical compositions. Hence, this study aimed to assess the geographical origin variations in the fatty acids composition of white sesame seeds. For this, fifty three white sesame seed samples from the five major producing areas (Humera, Metema, West Armachiho, Wolkayiet, Tach Armachiho) were analyzed for their fatty acid compositions using gas chromatography coupled with mass spectrometry (GC-MS). Nine different fatty acids were detected in all of the samples. The sesame seeds were rich in the essential fatty acids, linoleic acid and oleic acid, which were the most abundant fatty acids in the seeds with percentage compositions in the range 35.3‒48.3% and 29.8‒38.2%, respectively, across the different samples. These two fatty acids together accounted for 72.0‒78.8% of the total fatty acids in the samples, whereas 19.8‒22.0% was accounted jointly by palmitic acid and stearic acid while trace levels (all together 1.34‒2.32%) were palmitoleic acid, margaric acid, gadoleic acid, arachidic acid, and behenic acid. The seed oils showed high unsaturated-to-saturated fatty acid ratio in the range of 2.98‒3.70, which is high enough to satisfy most dietary guidelines. The oleic acid to linoleic acid ratio of the seed oils were in the range of 0.80–0.97, where the highest was found in seeds from Humera. Regarding the individual fatty acids, a significant variation (p < 0.05) among production areas was observed only for palmitic acid and palmitoleic acid, where the highest concentrations were found in seeds from Humera (14.9±1.5% palmitic acid and 0.25±0.04% palmitoleic acid).

Advances in Floral Senescence: Molecular Mechanisms and Ethylene Regulation

2024-12-18T06:23:08+00:00

Abstract

Floral senescence, the process by which flowers age and eventually die, is a critical factor affecting flower longevity and quality, especially in the high-value floriculture industry. This review synthesizes recent advancements in understanding the complex molecular and hormonal mechanisms that govern floral senescence, with a particular focus on the role of ethylene. Ethylene is a key regulator of floral aging, orchestrating the process through intricate genetic and signaling networks. It influences key transcription factors, such as Ethylene Response Factors (ERFs), and senescence-associated genes (SAGs), which collectively drive the aging process. The review begins by outlining the growth of the floriculture industry and the significance of floral senescence, detailing the physiological and molecular changes that occur during this phase. It explores the roles of various plant hormones—including ethylene, cytokinins, polyamines, and abscisic acid—in modulating senescence and their implications for flower quality. Key advancements in ethylene research are highlighted, including its biosynthesis, signaling pathways, and interactions with other hormonal and genetic regulators. The review also discusses the impact of ethylene on gene expression patterns and the technological interventions developed to manage its effects, such as ethylene inhibitors and genetic engineering approaches. By integrating insights into ethylene's role and its interaction with other hormonal pathways, this review offers a comprehensive understanding of floral senescence and its implications for flower preservation. The advancements outlined provide new opportunities for extending flower longevity and optimizing agricultural practices, with potential benefits for both ornamental and crop species. Future research directions are proposed to address existing knowledge gaps and enhance plant health and productivity.