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Search Results: 1 - 10 of 27 matches for " Letemichael Negash "
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Antibiotic Resistant Bacteria from Treated and Untreated Hospital Wastewater at Ayder Referral Hospital, Mekelle, North Ethiopia  [PDF]
Tsegahun Asfaw, Letemichael Negash, Amlsha Kahsay, Yemane Weldu
Advances in Microbiology (AiM) , 2017, DOI: 10.4236/aim.2017.712067
Abstract: The widespread emergence of antibiotic resistance among bacterial pathogens has become one of the most serious challenges in Ethiopia. This study determined the prevalence and drug resistance patterns of bacterial pathogens isolated from treated and untreated wastewater released from Ayder Referral Hospital in Northern Ethiopia. A cross sectional study design was conducted from September-December, 2015 in wastewater released from Ayder referral hospital. A total of 40 composite samples were aseptically collected, transported and processed for enumeration of indicator organisms, bacteriological identification and susceptibility testing following standard procedure. Data obtained were entered and analyzed using SPSS version 20. Mean heterotrophic plate count, total coliform count, fecal coliform count and E. coli count were found to be 1.6 × 106 CFU/mL, 2.2 × 106 CFU/100 mL, 2.0 × 105 CFU/100 mL and 1.1 × 104 CFU/100 mL from treated wastewater respectively. Among the total samples 134 bacterial isolates were detected and [84 (62.7%)] were from untreated wastewater and [50 (37.3%)] were from treated wastewater. The most frequently isolated bacteria from untreated wastewater samples was Klebsiella spp [14 (16.7%)] followed by S. aureus [13 (15.5%)] and P. aeruginosa [12 (14.3%)], similarly in treated wastewater samples Klebsiella spp [10 (20%)], P. aeruginosa [8 (16%)] and S. aureus [8 (16%)] were frequently detected. The overall multi-drug resistance (MDR) in this study was [79/134 (79.1%)]. MDR from untreated wastewater sample was [64/84 (76.2%)] while from treated wastewater sample was [42/50 (84%)] and shows significant difference with (COR: 1.64, 95% CI: 1.15 - 3.29, P: 0.001). It is concluded that treated hospital wastewater contains large numbers of antibiotic resistant bacteria. Therefore, there should be continuous monitoring and evaluation of the effluent quality of the ponds and chlorination of the final effluent should be developed.
Analysis of Rainfall Intensity-Duration-Frequency Relationship for Rwanda  [PDF]
Negash Wagesho, Marie Claire
Journal of Water Resource and Protection (JWARP) , 2016, DOI: 10.4236/jwarp.2016.87058
Abstract: Global atmospheric and oceanic perturbations and local weather variability induced factors highly alter the rainfall pattern of a region. Such factors result in extreme events of devastating nature to mankind. Rainfall Intensity Duration Frequency (IDF) is one of the most commonly used tools in water resources engineering particularly to identify design storm event of various magnitude, duration and return period simultaneously. In light of this, the present study is aimed at developing rainfall IDF relationship for entire Rwanda based on selected twenty six (26) rainfall gauging stations. The gauging stations have been selected based on reliable rainfall records representing the different geographical locations varying from 14 to 83 years of record length. Daily annual maximum rainfall data has been disaggregated into sub-daily values such as 0.5 hr, 1 hr, 3 hr, 6 hr and 12 hr and fitted to the probability distributions. Quantile estimation has been made for different return periods and best fit distribution is identified based on least square standard error of estimate. At-site and regional IDF parameters were computed and subsequent curves were established for different return period. The moment ratio diagram (MRD) and L-moment ratio diagram (LMRD) methods have been used to fit frequency distributions and identify homogeneous regions for observed 24-hr maximum annual rainfall. The rainfall stations have been divided into five homogeneous rainfall regions for all 26 stations. The results of present analysis can be used as useful information for future water resources development planning purposes.
A Review of Effective Waste Management from an EU, National, and Local Perspective and Its Influence: The Management of Biowaste and Anaerobic Digestion of Municipal Solid Waste  [PDF]
Mebrahtom Negash Araya
Journal of Environmental Protection (JEP) , 2018, DOI: 10.4236/jep.2018.96041
Abstract: The waste management industry across the European Union (EU) has undergone radical change following the recognition that a move towards a sustainable society is essential for humankind. To this end, the EU has targeted household recycling targets of 50% by 2020 and 70% by 2030 in a bid to move towards a more sustainable and resource efficient society. Despite such targets and a number of relevant progresses in technology (such as incineration, composting, and anaerobic digestion), there are several challenges facing the municipal solid waste sector. The purpose of this review is to assess the EU, UK and local policies that are affecting the way waste is treated, Greater Manchester (GM) in the United Kingdom (UK), will be used as an example. The review focuses upon anaerobic digestion as a choice technology for waste management and assesses the influences of policies upon the application of anaerobic digestion at the EU and local level, finding that at current rates of recycling, local and national targets will be missed by approximately 7.3% in the year 2030, even in the best case scenario where the maximum amount of biowaste is managed under the current operational capacity. The review concludes that in order to improve the recycling bio-waste capacity on a local, national, and EU level, the introduction of the AD must be increased tremendously.
Graduate Competency,Teaching Effectiveness and Faculty Performance Evaluation: An International Perspective
Minga NEGASH
Revista Romaneasca pentru Educatie Multidimensionala , 2012,
Abstract: This paper examines the relationship between graduate workplace competency standards and teaching effectiveness (competency) evidences used in colleges and universities. The cognitive, emotional and soft skills of students and academics, and teaching performance evaluation systems at two unrelated tertiary institutions were studied. The paper documents that teaching effectiveness instruments in use at two institutions, and by extension in several institutions do not measure the cognitive skills (core competency) of the professor, and the summative questions appear to relate to the individual’s soft skills. The diagnostic feedback given to the professor neither logically connect to improved teaching and learning outcomes, nor does it enable the individual to obtain improved scores in key summative performance evaluation questions. The implications of the finding for quality assurance in teaching and learning, graduate competency, faculty tenure and promotion, and international comparisons of academic qualifications are discussed.
Assessment of the Ecological Status and Threats of Welala and Shesher Wetlands, Lake Tana Sub-Basin (Ethiopia)  [PDF]
Negash Atnafu, Eshete Dejen, Jacobus Vijverberg
Journal of Water Resource and Protection (JWARP) , 2011, DOI: 10.4236/jwarp.2011.37064
Abstract: The ecological status of the Welala and Shesher Wetlands, on the eastern side of Lake Tana, were studied during pre-rainy, main-rainy, post-rainy and dry seasons from May 2009 to January 2010. Species composition, diversity and abundance of macrophytes, benthic macro-invertebrates and birds were assessed and physico-chemical parameters were measured. Phosphate and silicate concentrations, conductivity, TDS and turbidity varied significantly (p < 0.05) between dry and wet seasons in both wetlands. Physico-chemical parameters did not differ (p > 0.05) between the two wetlands. The values for dissolved oxygen and pH ranged between 4.8 - 7.8 mg/l and 6.7 - 7.6, respectively. The values for nitrate and phosphate ranged between 0.2 - 3.1 mg/l and 0.2 - 3.3 mg/l, respectively. A total of 274 benthic macro-invertebrate individuals belonging to 5 families were collected, 32, 699 individual birds belonging to 62 species were enumerated and 13 species of macrophytes were identified. The two wetlands are shrinking at an alarming rate, mainly because of unsustainable farming practices and a huge irrigation project on Ribb River which is at presently under construction. Farming practices include draining and pumping of water for irrigation and expansion of farmland at the cost of the wetlands. The construction of a dam in Ribb River prevents overflow from Ribb River into the wetlands and disrupts the connection with Lake Tana which is vital for the survival of these two wetlands. We conclude that the Welala and Shesher Wetlands are valuable wetlands which need urgently protection.
Flow Injection Amperometric Determination of Phenol and Chlorophenols at Single Wall Carbon Nanotube Modified Glassy Carbon Electrode  [PDF]
Negussie Negash, Hailemichael Alemu, Merid Tessema
American Journal of Analytical Chemistry (AJAC) , 2014, DOI: 10.4236/ajac.2014.53023
Abstract:

Single wall carbon nanotube modified glassy carbon electrode (SWCNT/GCE) was used for flow-injection analysis (FIA) for phenolic compounds (phenol (P), 4-chlorophenol (CP), 2,4-dichlorophenol (DCP), 2,4,6-trichlorphenol (TCP) and pentachlorophenol (PCP)). Experimental variables such as the detection potential, flow rate and pH of the carrier solution, 0.1 M sodium acetate, were optimized. Under these conditions, the designed electrode showed a very good performance for the amperometric measurements, with no need to apply a cleaning or pre-treatment procedure. The operational stability was tested with 20 repetitive injections of each analyte and was found to be good. The analytical performance of the SWCNT/GCE electrode under flow through conditions was tested and was found to be impressive. When it is compared with other enzymatic and non-enzymatic sensors, it shows wider dynamic range for the detection of phenolic compounds with low limits of detection. These results suggest that the method is quite useful for monitoring and analyzing phenols and chlorophenols.

Severe malaria among children in Gambella, western Ethiopia
Betemariam Gebre, Yayeh Negash
Ethiopian Journal of Health Development , 2002,
Abstract: [Ethiop. J. Health Dev. 2002;16(1): 61-70]
Prevalence of HIV/AIDS: A report based on a survey in women attending ANC services in Eritrea in 2005
T Negash, A Tesfazion
Journal of the Eritrean Medical Association , 2006,
Abstract: Study objective: To determine the prevalence and socio-demographic factors of HIV in ANC attendees in Eritrea. Methods: Cross sectional anonymous unlinked sentinel surveillance of HIV prevalence in ANC attendee pregnant women frpm March 2005 to May 2006. The study was conducted in 15 clusters; 10 urban and 5 rural clusters with a total of 19 urban and 26 rural sentinel sites that includes all six capital cities and a number of semi urban and rural sentinel sites from all six zones of Eritrea. Cluster sampling, non probability consecutive sampling of pregnant women who came to attend their first ANC in the study sites. Result: The total sample size was 5033. The over all HIV prevalence in pregnant women attending ANC was 2.38%. The highest prevalence was observed in Southern Red Sea zone (5.9%) followed by central zone (3.48%). Lowest prevalence was seen in Anseba zone (1.3%), South zone (1.65%), Northern Red Sea zone (1.77%), and Gash Barka zone (2.06%). It was found to be 3.04% in urban women and 0.9% in rural women. It was also higher in single women 7.2% than in married women 2%. HIV prevalence increased with age (1.3%) in women aged 15-19, 2% in 20-24, 3.8% in 25-29, 2.5% in 30-34, 1.5% in 35-39, 2.7% in 40-44 and 1.8% in 15-24 years age group women. Further the prevalence fluctuated with level of formal education and occupation; 0.9% in illiterate and 4% in women with secondary school education, 1.94% in house wives, 5.9% in women daily labourers, 5.6% in unemployed unmarried women, and 8.5% in commercial sexual workers. 5.4% in women whose partners are truck/bus drivers, 3.8%% in women whose partners are merchants and 2.6% in women whose partner’s are in the military/national service. Conclusion: HIV prevalence in Eritrea is low and declining from the highest 4.2% in 1999 to 2.38% in 2005 ANS sentinel surveillance. HIV prevalence was more prevalent in urban areas, in single, young women and increased with increasing age and educational level and was influenced by the women’s and partners occupation.
Perchlorate-selective liquid membrane electrodes based on crystal violet and brilliant green and their analytical applications
Negussie Negash, Ghirma Moges, Bhagwan Singh Chandravanshi
Bulletin of the Chemical Society of Ethiopia , 1995,
Abstract: Bull. Chem. Soc. Ethiop. 1995, 9(2), 65-77.
Reproductive biology in the medicinal plant, Plumbago zeylanica L.
B Abera, L Negash, J Kumlehn
African Journal of Biotechnology , 2008,
Abstract: Plumbago zeylanica L. is an important medicinal plant traditionally used for the treatment of various diseases. Phenology from seed germination via vegetative growth to reproductive development was studied under glasshouse and nursery conditions. Seeds rapidly germinated on a mixture of nursery soil and cattle dung in a ratio of 3:1 filled in pots or on cultivated soil under nursery conditions as a prerequisite for vegetative and flowering phenological studies. Hypogeal germination characterizes the emergence of seedlings. Subsequent vegetative and flowering phenology between glass house and nursery field populations showed significant difference (p <0.05) in terms of time, duration and yield. Glass house populations completed their phenophases (seasonally) (72.3 ± 1.03%) within 133 days (15 March to 20 July, 2006) being under controlled conditions while field-grown seedlings extended to 225 days (15 March to 30 November, 2006) after seed sowing. Rainy season was the cause for the continuous damage of apical shoots, and consequently stunted vegetative growth of field-grown seedlings. Plant size ( 95 cm in height), leaves number (33 - 38) and seasonal climate (cold season for field-grown populations) were found to be the most eliciting signals for the initiation of flowering buds. 100 ppm GA3 was the most effective for early flowering (that is, before 6 days) and production of higher number of flowers (32.6 ± 1.6%) compared to the control (22.5 ± 1.33%). The mode of reproductive biology appeared to be cross-pollination and showed significant (p <0.05) compared to the control. The final flowering percentage (95.3 ± 1.71%) and/or seed-set (89.4 ± 1.41%) were obtained under glass house condition compared to the nursery, which dropped as low as 50% in flowering and seed-set. The study found that rainy season, plant size, leave number, low temperature, cross pollination and glass house conditions were found to be the most determining factors for the phenology of P. zeylanica.
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