Ethiopian Journals Online (EJOL)
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COMPARISON OF SEISMIC PROVISIONS OF EBCS 8 AND CURRENT MAJOR BUILDING CODES PERTINENT TO THE EQUIVALENT STATIC FORCE ANALYSIS
No full textA comparison of seismic ptovisions havingrelevance to the Equivalent Static Force (ESF)method of analysis according to current majorbuilding codys worldwide is presen!ed. The codescompared include the latest two editions of theUniform Building Code (UBC 94 and UBC 97), theInternational Building Code (IBC 2000), theEuropean Prestandard (Eurocode 8, 1998), and theEthiopian Building Code Standard (EBCS 8, 1995).The comparison is mady on the basis of thespecified base shear coefficient, the verticaldistribution of the base shear, the story shear andoverturning moment, the considerations for torsion,P-delta effect, and the limitations on the story drift.Substantial differences are observed among thecodes and even within different editions. of~ code,a good example being the UBC series. It is alsoshown that the most recent American codes likeUSC 97 and IBC 2000 exhibited drastic changes inthe definition of the base shear coefficient and inother pertinent regulations as compared to theclassical forms familiar to most users
REVERSE ACTION OF ON-LOAD TAP-CHANGER TRANSFORMER
No full textIn this paper expression is derived that shows thecondition for instability of un-load tap-r::hanger(DLTe) transformer controlling the voltage of animpedanae load. Use of sensitivity and eigenvalueanalysis to predict voltage collapse is discussed
INFORMATION SECRECY AND PUBLIC-KEY CRYPTOGRAPHY
No full textThe subject and need of information secrecy withemphasis to the choice of fully using an alreadyestablished public channd is to be discussed.Related histories and current achievements madein the area of information hiding, notable personswho changed the course OJ its progress fromancient times to this last generation are to bei'rltroduced with the intention of making every one.alert of the subject and the pitfalls of anunprotected information being conveyed on apublic channel particularly in the areas of bankingand financial related sectors and every one usingsuch global networks a~ the Interne
Ethanol, methanol, acid content and other quality parameters of Ethiopian traditional fermented, distilled and factory-produced alcoholic beverages
No full textDirect human-caused wildlife mortalities in Geralle National Park, southern Ethiopia: implications for conservation
No full textThis paper aims to report records of direct human-caused wildlife mortalities in the Geralle National Park of southern Ethiopia during the last five years (2013-2017). Our data showed that a total of 102 carcases of wild mammals were recorded during the period under report, representing 13 species most of which are currently globally threatened. On average 21 ± 5 animals were killed each year and nearly three-fourth of affected species and individuals killed were carnivores. Causes of mortality for all the cases reported were identified as deliberate gun-shooting (n=72, or 71% of the total) or car accident (n=30; 29%). The main reasons why the local people were motivated to commit deliberate killing of carnivores using rifles were in revenge to livestock depredation and that of ungulates to meet their demand for bushmeat. Although the motivation behind road killing was not clearly understood, lack of awareness or accidents due to high speed driving could be possible reasons. In addition to mammals, 33 carcases of four bird species were recorded during the study period, including the vulnerable Somali Ostriches (Struthio camelus) and the critically endangered African White-backed vulture (Gyps africanus), the latter due to unintentional poisoning. The data in this study pointed out that direct human-caused wildlife mortalities are one of the major threats to several wildlife species in the park, which may hold true in other protected areas of the country as well. Thus, awareness raising education on the consequences of direct human-caused wildlife killing on the species involved and ecosystem and implementation of effective law enforcement should be viewed as an urgent management intervention to curtail such wildlife mortalities in the park. Specific recommendations that are assumed to be practically applicable are also provided
Studies on butterflies’ diversity in relation to habitats and seasons at Gulele Botanical Garden in Central Ethiopia: implication of protected area for in-situ conservation of biological entity
No full textButterflies are the most important biodiversity components, which are under different threats including climate change that varies with habitat type and seasons. Intra-annual variation in temperature (i.e. seasonality) can have important implications for thermal tolerance, which affect climate change vulnerability. Habitat type can additionally influence a population’s capacity to respond to climatic change. As Gullele Botanical garden is home of small animals like butterflies owing to its different habitats in different seasons, studying the diversity of these useful group of organism is vital. The study was conducted from July 2012 to June 2014. Butterfly diversity was investigated using sweep nets along transects (500 m x 300 m) in three types of habitats: natural forest, artificial forest and Grassland. Data were analyzed using Xcel Software, Tukey’s hsd test and diversity indexes. Maximum abundance (162) and species richness (26) was recorded in grassland followed by natural forest though they are not statistically different (p>0.05). Butterflies evenly distributed in the three habitats (P>0.05). The highest Shannon diversity index was at the grassland (H=3.09) followed by the natural forest (H=3.02). The species richness index was the highest (R=4.91) in the grassland and the least (R=3.79) in the artificial forest. Simpson’s diversity index indicated higher butterfly species diversity in the natural forest (D=0.92) and grassland habitat (D=0.96). Members of the family Lycaenidae were the most dominant (28.5%) and Hesperidae (8.03%) was the least. There was a significance difference (P<0.05) among seasons. Multiple comparisons of Tukey hsd test showed that there was a significant (P<0.05) difference between autumn and winter. Species richness showed the maximum (R=6.06) record in autumn and minimum (R=4.10) in winter. Shannon diversity index showed higher diversity (H=3.396) in autumn. Among families, Lycaenidae had high values in autumn (H=1.09) and spring (H=1.03), while Nymphalidae and Pieridae had high values during winter (H=0.952) and summer (H=0.980), respectively. Hesperiidae had the highest value (H=0.32) in autumn and the lowest (H=0.00) in winter. In Artificial forest Hypolimnas salmacis (Rothschild & Jordan), Bicyclus campus (Karsch) and Euchrysops albistriata (Capronnier) were abundantly found. Deudorix dinochares (Grose-Smith) and Papilio echerioides (Trimen,) were species specific to the natural forest habitat. The most abundant species in the grassland were Eicochrysops messapus (Wallengren), Colias electo (Berger) and Danaus chrysippus (L.)
Food and feeding habits of juvenile and adult Nile tilapia, Oreochromis niloticus (L.)(Pisces: Cichlidae) in Lake Ziway, Ethiopia
No full textOreochromis niloticus (Nile tilapia) is an important fish in the ecology of tropical and subtropical aquatic ecosystems. The fish is commercially the most important fish species in Ethiopian water bodies including Lake Ziway. In recent years, the fish community structure and ecosystem dynamics of Lake Ziway have changed, but no studies have been carried out to assess whether the fishes have altered their diets in the lake. This study investigated the food and feeding habits of Nile tilapia from April to August 2017 in Lake Ziway, Ethiopia. A total of 365 Nile tilapia specimens (170 adults and 195 juveniles) were collected ranging from 2.5 to 30 cm TL and 0.5 to 459.7 g tw. Adult fish samples were obtained from the catches of fishermen, while the juveniles were collected from three sampling sites which were located in the shallow part of the lake. Guts of 165 (85%) juveniles and 115 (73.5%) adults that contained food items in their stomachs were analyzed using the frequency of occurrence and volumetric methods. Volumetrically, the major diets of juveniles were zooplankton (33.79%), phytoplankton (25.44%), insect (18.69%), and detritus (14.02%) while the diet of adults were mainly macrophytes (36.2%) followed by phytoplankton (34.36%) and detritus (18.41%). Nile tilapia, which was a phytoplanktivorous fish, has now consumed predominately macrophytes even though phytoplankton is the second dominant food item. Juvenile Nile tilapia depends on zooplankton and insect larvae. The study demonstrates that juveniles mainly fed on animal-based food items whereas the adult fed primarily on macrophytes followed by phytoplankton food items. We have discussed the possible causes of macrophytes as a major diet of adult Nile tilapia. This study contributes to the sustainable utilization of Nile tilapia and for the development of the aquaculture industry
ANALYSIS OF GENETIC DIVERSITY IN LINSEED USING AFLP MARKERS
No full textLinseed (Linum usitatissimum L.) is the second most important oilseed crop in thehighlands of Ethiopia where it has been cultivated for its valuable seed-oil since antiquity. Sixtyaccessions of linseed predominantly from Ethiopia were analysed using amplified fragment lengthpolymorphism (AFLP) markers to assess their genetic diversity. Out of seven pairs of AFLP primersscreened, Eco-ACA/ Mse-CAT and Eco-ACA/ Mse-CTT resulted in a greater number of amplificationproducts. The estimated genetic distance for pairwise accessions significantly (P < 0.001) varied from0.29 to 0.71, indicating the prevalence of genetic diversity in both exotic and local collections.Introductions from Canada and collections from different parts of Ethiopia, especially those fromcentral and northwest regions revealed considerable variations between and within their geographiclocations and thus can be used to create genetic variations. Cluster analysis categorized the 60accessions into 13 classes, each consisting of one to 14 accessions. Two introduced accession wereindividually clustered, showing their greater divergence. AFLP analysis was found effective indiscriminating the accessions and in selecting suitable parents for future genetic improvement. It wasalso useful for efficient management of genetic resources, eliminating unnecessary duplication
Tuberculosis Knowledge, Attitude and Preventive Practices among Patients Visiting Selam Public Health Center: A Cross-Sectional Study
No full textTuberculosis (TB) remains the major public health problem and killed over 49,000 people in 2016 alone and continues to be the major challenge of the country. This study aimed to assess tb knowledge, attitude and practice (KAP) of patients who visited Selam Health Center (SHC), Gullele sub-city in the north of Addis Ababa. A cross-sectional study was conducted from the beginning of February to the end of March 2019. A well-structured questionnaire was used to collect patients’ kap data. Quantile regression model was used to analyze the association between dependent and independent variables. A total of 384 shc patients were enrolled. All respondents had heard about tb, 65.9% described tb as a very serious disease and 61.2% mentioned bacteria as causative agent. Almost 60% don’t know the mode of transmission of tb and 56.2% identified the major symptoms of tb. Majority (72.9%) of them had an unacceptable attitude towards tb patients. Nearly 80% sought treatment after two weeks of symptoms, 52.9% preferred health centers, while 47.1% refused to go to health centers because of costs, lack of trust on health workers, transportation problems and fear of job loss. Quantile regression analysis revealed that there was a statistically significant correlation between knowledge and attitude (rs = 0.01, p = 0.007) and attitude and practice (rs = 0.14, p = 0.021). The present findings revealed that patients’ knowledge on cause and symptoms of tb was fairly high but most failed to know the route of transmission and perceived a negative attitude towards tb patients. Health centers and other stakeholders should provide health education and health extension services for the community to reduce the spread of tb and its consequence