Ethiopian Journals Online (EJOL)
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An Evidence of Past Introgressive Hybridization Between Labeobarbus Ethiopicus and L. Intermedius in the Ethiopian Rift Valley, East Africa
No full textAnalyses of nucleotide sequences of mitochondrial DNA (cytochrome b fragment) in 30 common barbs (Labeobarbus intermedius) from Lake Langano in the Ethiopian Rift Valley revealed the genetic heterogeneity of the samples. Whereas 29 individuals shared the same haplotype similar to those found in the poorly structured assemblage of L. intermedius sensu lato inhabiting the Rift Valley and basins of western Ethiopia, a single individual possessed a haplotype found exclusively in small-scaled Ethiopian barb L. ethiopicus. The latter species is phylogenetically distant from L. intermedius from any Ethiopian basins and differs from it by the substantially increased lateral line scale counts. Labeobarbus ethiopicus is the narrow range endemic of the Lake Zway basin. Presently barb migration from Zway to Langano is impossible because of the high water mineralization of Lake Abijata located on route. Past introgressive hybridization between two barb species could be enhanced by higher water level in the Zway-Langano-Abijata-Shala lake basin during humid periods in the course of paleoclimatic oscillations. Additionally, the increased lateral line scale counts were found in the Langano barbs compared to other barb population from the central part of the Ethiopian Rift valley, while the barbs from this region exhibited the increased values of this character compared to any other L. intermedius populations from Ethiopia and Kenya. These increased values could be a result of gene flow from L. ethiopicus to L. intermedius. The endangered status of L. ethiopicus as well as L. intermedius population from lakes Zway and Langano is highlighted
The Ethiopian Flora Project: Past, Present and Future – An Editor’s View
No full textA brief account of some of the problems experienced during the 29 years of editing is given, as well as comments on how the Flora of Ethiopia and Eritrea is being used at present. The urgent need to produce regional and local Floras is stressed and the instrumental role of the Flora in this connection is emphasized. The distribution of the Flora volumes is touched upon as well as the need for an electronic versio
ANALYSES OF TEN-YEAR MALARIA TRANSMISSION DYNAMICS IN RELATION TO METEOROLOGICAL VARIABLES IN JABI TEHNAN DISTRICT, NORTHWEST ETHIOPIA
No full textRetrospective studies of malaria cases from health facilitiesand the impact of meteorological factors provide insight into the dynamics ofmalaria transmission and the effectiveness of malaria control interventions.This study aimed to analyze inter-annual and monthly trends in malaria casesand determine the correlations between meteorological variables andprevalence of malaria. Retrospective data on malaria cases were extractedfrom 11 health centres and 39 health posts in Jabi Tehnan district, northwestEthiopia, for 10 years (July 2011–May 2021). Trends in monthly and annualmalaria cases were analyzed and correlated with meteorological data. Of1,500,868 individuals with febrile complaints examined at the health facilitiesin the district, 13.4% were diagnosed as clinical malaria cases. Furthermore,12.6% of those with febrile symptoms had malaria confirmed withmicroscopy and with rapid diagnostic test (RDT). Plasmodium falciparumcomprised 56.48%, with 36.56% P. vivax, and with 6.96% mixed (P.f + P.v)infections. There were significant variations in inter-annual and monthlymalaria cases (P<0.001; P = 0.004, respectively). Malaria cases peaked in2011–2013, and 2015–2016, with reduced and relatively lower malaria casesin 2017–2021. Two malaria peaks in May-June, and in October-Novemberwere recorded. Inter-annual and monthly malaria trends were closelycorrelated with relative humidity and average temperatures. Plasmodiumfalciparum was predominant compared to P. vivax. Understanding trends inmalaria transmission in relation to climatic variables, and monitoring theeffectiveness of malaria control interventions are needed to reduce malaria inthe area
What is Chemical Engineering?
No full textAs was noted in the editorial of the second issue of Zede, the chemical engineeringfield has already experienced lack of people in the profession. There is only one Ethiopianchemical engineer in the major established chemical process industries: sugarand cement mills and petroleum refinery. A paper mill which is to be integrated witha pulp mill at a later stage is under construction. Expansions or vertical and hori=ontalintegration of these or similar industries and the establishment of new ones may beexpected in the not too distant future. If something concrete is not done now the dependencyof the country on expatriate chemical engineers will be more and moreacute. The objective of this article is, therefore, mainly to inform students at highschool and college levels what chen1ical engineering is and what it has in store forthem and the country
Development of the Awash Valley
No full textThe Awash River is the only large river which starts and ends within the Empire. It starts from the Highlands of Ginchi, Shoa Governorate General and flows towards the east and north of the country for a total length of about l,200 kms.forming the Awash Valley. Since the valley has considerable potential in water resources, irrigable lands, livestock development and other resources as well and because of its favourable geographical location, its proximity to the market centers and to the sea ports and because of the net work of transportation facilities it enjoys the needs for its immediate development are quite obvious. It was with this in view that in 1962 the Ethiopian Government established the Awash Valley Authority (AV A) as an autonomous public authority to administer and develop the natural resources of the Valley
The Convergence Characteristic of the Fast Decoupled Load Flow Technique
No full textA Fortran program is written using matrix sparsity for the inversion of the coefficient matrix and two aspects of the convergence characteristic of the fast decoupled load flow technique are investigated. These are, effects of the starting values and effects of R/X ratio of transmission lines. The analysis is based on computational results and not on theoretical study. A threshold level of R/X ratio above which convergence is not reliable is determined
Biaxial charts for rectangular reinforced columns in accordance with the Ethiopian building code standard EBCS-2:Part1
No full textThe analysis of reinforced concrete sections are characterised by material non-linearity arising from the non-linear stress-strain relationships and the cracking of the cross-section. · As a result, the systematic production of biaxial design charts necessitates the application of numerical methods that are based on iterations. The design charts may be conveniently represented as My-M: diagrammes on planes of constant internal normal forces or as N-M diagrammes on planes of constant angles that relate the y- and z-components of the resultant moment M. The aim of this paper is to present an iterative procedure that has been successfully used to produce biaxial charts of the first type. The design charts are produced for biaxially loaded rectangular columns in accordance with the Ethiopian Building Code Standard, EBCS-2: Part l [/]