The mineralogy and petrography of natural graphite in Saba Boru of Ethiopia indicate that there exists flake graphite with a slightly oval structured fine size according to our study on thin and polished sections.Here...The mineralogy and petrography of natural graphite in Saba Boru of Ethiopia indicate that there exists flake graphite with a slightly oval structured fine size according to our study on thin and polished sections.Herein,for estimating the carbon content in graphite,the ASTM-C561,the test method for ash in a graphite sample,was used.For characterizing graphite,x-ray diffraction,x-ray fluorescence,inductively coupled plasma mass spectroscopy,and scanning electron microscopy were also used.Chemical analysis of ore samples determined that the average compositions are 63.35%SiO2,15.45%Al2O3,2.36%Fe2O3,2.07%K2O,less than1%others,and loss-on-ignition(LOI)in the range of^4.74%–37.42%.The total carbon content of graphitic ore ranged from 4.11%to 33.14%.Importantly,when graphite is concentrated through floatation,its average purity and recovery are 92.97%and 90.82%,respectively.Furthermore,once the graphite concentrates are treated with hydrofluoric acid,the average value attains a high grade of 96.48%C.Moreover,the average ash content is 81.93%(pre-flotation)and 3.1%(post-flotation),respectively.Finally,after beneficiation,a silica is identified as a major gangue(85.88%),usable as a raw material for other purposes such as cement.Hence,these graphite-bearing rocks seem to be worth exploring for commercialization opportunities.展开更多
Objective:To evaluate the activity of selected Ethiopian medicinal plants traditionally used for wound treatment against wound-causing bacteria.Methods:Samples of medicinal plants(Achyranthes aspera,Brucea antidysente...Objective:To evaluate the activity of selected Ethiopian medicinal plants traditionally used for wound treatment against wound-causing bacteria.Methods:Samples of medicinal plants(Achyranthes aspera,Brucea antidysenteriea,Datura stramonium,Croton macrostachyus,Acokanthera xchimperi.,Phytolacca dodecandra,Milhttia ferruginea,and Solanum incanum)were extracted using absolute methanol and water and tested for their antimicrobial activities against clinical isolates and standard strains of wound-causing bacteria using agar well diffusion and micro titer plate methods.Results:Most of the plant extracts had antibacterial activities,among which Acokanthera schimperi and Brucea antidysenteriea inhibited growth of 100%and 35%of the test organisms,respectively.Methanolic extracts had higher activities compared with their corresponding aqueous extracts.The most susceptible organism to the extracts was Streptococcus pyogens while the most resistant were Escherichia coli and Proteus vulgaris.Conclusions:This finding justifies the use of the plants in wound healing and their potential activity against woundcausing bacteria.Their toxicity level and antimicrobial activity with different extraction solvents should further be studied to use them as sources and templates for the synthesis of drugs to control wound and other disease-causing bacteria.展开更多
Soil loss by runoff is a severe and continuous ecological problem in Koga watershed.Deforestation,improper cultivation and uncontrolled grazing have resulted in accelerated soil erosion.Information on soil loss is ess...Soil loss by runoff is a severe and continuous ecological problem in Koga watershed.Deforestation,improper cultivation and uncontrolled grazing have resulted in accelerated soil erosion.Information on soil loss is essential to support agricultural productivity and natural resource management.Thus,this study was aimed to estimate and map the mean annual soil loss by using GIS and Remote sensing techniques.The soil loss was estimated by using Revised Universal Soil Equation(RUSLE)model.Topographic map of 1:50,000 scale,Aster Digital Elevation Model(DEM)of 20 m spatial resolution,digital soil map of 1:250,000 scale,thirteen years rainfall records of four stations,and land sat imagery(TM)with spatial resolution of 30 m was used to derive RUSLE's soil loss variables.The RUSLE parameters were analyzed and integrated using raster calculator in the geo-processing tools in ArcGIS 10.1 environment to estimate and map the annual soil loss of the study area.The result revealed that the annual soil loss of the watershed extends from none in the lower and middle part of the watershed to 265 t ha^(-1) year^(-1) in the steeper slope part of the watershed with a mean annual soil loss of 47 t ha^(-1) year^(-1).The total annual soil loss in the watershed was 255283 t,of these,181801(71%)tones cover about 6691(24%)hectare of land.Most of these soil erosion affected areas are spatially situated in the upper steepest slope part(inlet)of the watershed.These are areas where Nitosols and Alisols with higher soil erodibility character(0.25)values are dominant.Hence,Slope gradient and length followed by soil erodibility factors were found to be the main factors of soil erosion.Thus,sustainable soil and water conservation practices should be adopted in steepest upper part of the study area by respecting and recognizing watershed logic,people and watershed potentials.展开更多
Objective:To assess the distribution of ABO blood group and their relationship with Plasmodium falciparum(P.falciparum) malaria among febrile outpatients who sought medical attention at Dore Bafeno Health Center,South...Objective:To assess the distribution of ABO blood group and their relationship with Plasmodium falciparum(P.falciparum) malaria among febrile outpatients who sought medical attention at Dore Bafeno Health Center,Southern Ethiopia.Methods:A total of 269 febrile outpatients who visited Dore Bafeno Health Center,Southern Ethiopia,were examined for malaria and also tested for ABO blood groups in January 2010.The blood specimens were collected by finger pricking,stained with Geimsa,and examined microscopically.Positive cases of the parasitemia were counted.CareStart^(TM) Malaria PflPv Combo was also used to test the blood specimens for malaria.ABO blood groups were determined by agglutination test using ERYCLONE antisera.Data on socio-demographic characteristics and treatment status of the participants were also collected.Chi-square and ANOVA tests were used to assess the difference between frequencies and means,respectively.Results:Out of a total of 269 participants,178(66.2%) febrile patients were found to be infected with Plasmodium parasites,among which 146(54.3%),28(10.4%),and 4(1.5%) belonged to P.falciparum,P.vivax,and mixed infections,respectively.All febrile patients were also tested for ABO blood groups and 51.3%,23.5%,21.9%and 3.3%were found to be blood types of 0,A,B and AB,respectively.Both total malaria infection and P.falciparum infection showed significant association with blood types(P<0.05).The proportion of A or B but not 0 phenotypes was higher(P<0.05) in individuals with P.falciparum as compared with non-infected individuals.The chance of having P.falciparum infection in patients with blood groups A,B and AB was 2.5,2.5 and 3.3times more than individuals showing blood 0 phenotypes,respectively.The mean P.falciparum malaria parasitemia for blood groups A,B,AB,and 0 were 3 744/μ L,1 805/ μ L,5 331/μ L,and1 515/μ L,respectively(P<0.01).Conclusions:The present findings indicate that individuals of blood groups A,B and AB are more susceptible to P.falciparum infection as compared with individuals o展开更多
Ethiopia has a mountainous landscape which can be divided into the Northwestern and Southeastern plateaus by the Main Ethiopian Rift and Afar Depression. Debre Sina area is located in Central Ethiopia along the escarp...Ethiopia has a mountainous landscape which can be divided into the Northwestern and Southeastern plateaus by the Main Ethiopian Rift and Afar Depression. Debre Sina area is located in Central Ethiopia along the escarpment where landslide problem is frequent due to steep slope, complex geology, rift tectonics, heavy rainfall and seismicity. In order to tackle this problem, preparing a landslide susceptibility map is very important. For this, GISbased frequency ratio(FR) and logistic regression(LR) models have been applied using landslide inventory and the nine landslide factors(i.e. lithology, land use, distance from river & fault, slope, aspect, elevation, curvature and annual rainfall). Database construction, weighting each factor classes or factors, preparing susceptibility map and validation were the major steps to be undertaken. Both models require a rasterized landslide inventory and landslide factor maps. The former was classified into training and validation landslides. Using FR model, weights for each factor classes were calculated and assigned so that all the weighted factor maps can be added to produce a landslide susceptibility map. In the case of LR model, the entire study area is firstly divided into landslide and non-landslide areas using the training landslides. Then, these areas are changed into landslide and non-landslide points so as to extract the FR maps of the nine landslide factors. Then a linear relationship is established between training landslides and landslide factors in SPSS. Based on this relationship, the final landslide susceptibility map is prepared using LR equation. The success-rate and prediction-rate of FR model were 74.8% and 73.5%, while in case of LR model these were 75.7% and 74.5% respectively. A close similarity in the prediction and validation rates showed that the model is acceptable. Accuracy of LR model is slightly better in predicting the landslide susceptibility of the area compared to FR model.展开更多
Background Neonatal jaundice is a common condition characterized by a yellowish discoloration of the skin,conjunctiva,and sclera caused by elevated serum or plasma bilirubin levels during the newborn period.The condit...Background Neonatal jaundice is a common condition characterized by a yellowish discoloration of the skin,conjunctiva,and sclera caused by elevated serum or plasma bilirubin levels during the newborn period.The condition is usually not dangerous,but it can progress to severe hyperbilirubinemia,which can lead to acute bilirubin encephalopathy and kernicterus,a bilirubin-induced neurological damage.Therefore,this study aimed to assess the pooled prevalence of neonatal jaundice and its determinants in Ethiopia.Methods Scopus,PubMed,Google Scholar,Embase,and CINAHL databases were searched for studies published between January 1,2010 and July 30,2021.A weighted DerSimonian Laird random-effects model was used to estimate the pooled prevalence of neonatal jaundice and its associated factors.The I2 was used to calculate the degree of heterogeneity.The funnel plot and Egger's regression test were used to assess publication bias.Results Totally 697 articles were generated from various databases,and the review included a total of eight articles.The pooled prevalence of neonatal jaundice was 30.96%[95%confidence interval(CI)16.61%–45.31%)]in Ethiopia.This review showed that prolonged labor[adjusted odd ratio(AOR)=3.39;95%CI 2.41–4.77),low birth weight(AOR=5.12;95%CI 3.11–8.72),birth asphyxia(AOR=3.75;95%CI 2.11–6.66),cephalohematoma(AOR=7.07;95%CI 2.72–18.38),ABO incompatibility(AOR=6.05;95%CI 2.95–12.42),Rhesus(RH)incompatibility(AOR=3.77;95%CI 2.04–6.96),male sex(AOR=4.53;95%CI 3.39–6.07),and neonatal sepsis(AOR=2.47;95%CI 1.49–4.08)were identified as a determining factor for neonatal jaundice in Ethiopia.Conclusions In low-and middle-income countries,neonatal jaundice is a significant healthcare burden,accounting for a significant portion of global childhood mortality and morbidity.However,some low-cost,effective,practical,and dependable solutions have been implemented.Prolonged labor,ABO incompatibility,RH incompatibility,birth asphyxia,neonatal sepsis,low birth weight,cephalohematoma,and male sex were 展开更多
基金This work was supported by Jimma Institute of Technology through Mega Project.
文摘The mineralogy and petrography of natural graphite in Saba Boru of Ethiopia indicate that there exists flake graphite with a slightly oval structured fine size according to our study on thin and polished sections.Herein,for estimating the carbon content in graphite,the ASTM-C561,the test method for ash in a graphite sample,was used.For characterizing graphite,x-ray diffraction,x-ray fluorescence,inductively coupled plasma mass spectroscopy,and scanning electron microscopy were also used.Chemical analysis of ore samples determined that the average compositions are 63.35%SiO2,15.45%Al2O3,2.36%Fe2O3,2.07%K2O,less than1%others,and loss-on-ignition(LOI)in the range of^4.74%–37.42%.The total carbon content of graphitic ore ranged from 4.11%to 33.14%.Importantly,when graphite is concentrated through floatation,its average purity and recovery are 92.97%and 90.82%,respectively.Furthermore,once the graphite concentrates are treated with hydrofluoric acid,the average value attains a high grade of 96.48%C.Moreover,the average ash content is 81.93%(pre-flotation)and 3.1%(post-flotation),respectively.Finally,after beneficiation,a silica is identified as a major gangue(85.88%),usable as a raw material for other purposes such as cement.Hence,these graphite-bearing rocks seem to be worth exploring for commercialization opportunities.
基金Supported by Aklilu Lemma Institute of Pathobiology.Addis Ababa University
文摘Objective:To evaluate the activity of selected Ethiopian medicinal plants traditionally used for wound treatment against wound-causing bacteria.Methods:Samples of medicinal plants(Achyranthes aspera,Brucea antidysenteriea,Datura stramonium,Croton macrostachyus,Acokanthera xchimperi.,Phytolacca dodecandra,Milhttia ferruginea,and Solanum incanum)were extracted using absolute methanol and water and tested for their antimicrobial activities against clinical isolates and standard strains of wound-causing bacteria using agar well diffusion and micro titer plate methods.Results:Most of the plant extracts had antibacterial activities,among which Acokanthera schimperi and Brucea antidysenteriea inhibited growth of 100%and 35%of the test organisms,respectively.Methanolic extracts had higher activities compared with their corresponding aqueous extracts.The most susceptible organism to the extracts was Streptococcus pyogens while the most resistant were Escherichia coli and Proteus vulgaris.Conclusions:This finding justifies the use of the plants in wound healing and their potential activity against woundcausing bacteria.Their toxicity level and antimicrobial activity with different extraction solvents should further be studied to use them as sources and templates for the synthesis of drugs to control wound and other disease-causing bacteria.
文摘Soil loss by runoff is a severe and continuous ecological problem in Koga watershed.Deforestation,improper cultivation and uncontrolled grazing have resulted in accelerated soil erosion.Information on soil loss is essential to support agricultural productivity and natural resource management.Thus,this study was aimed to estimate and map the mean annual soil loss by using GIS and Remote sensing techniques.The soil loss was estimated by using Revised Universal Soil Equation(RUSLE)model.Topographic map of 1:50,000 scale,Aster Digital Elevation Model(DEM)of 20 m spatial resolution,digital soil map of 1:250,000 scale,thirteen years rainfall records of four stations,and land sat imagery(TM)with spatial resolution of 30 m was used to derive RUSLE's soil loss variables.The RUSLE parameters were analyzed and integrated using raster calculator in the geo-processing tools in ArcGIS 10.1 environment to estimate and map the annual soil loss of the study area.The result revealed that the annual soil loss of the watershed extends from none in the lower and middle part of the watershed to 265 t ha^(-1) year^(-1) in the steeper slope part of the watershed with a mean annual soil loss of 47 t ha^(-1) year^(-1).The total annual soil loss in the watershed was 255283 t,of these,181801(71%)tones cover about 6691(24%)hectare of land.Most of these soil erosion affected areas are spatially situated in the upper steepest slope part(inlet)of the watershed.These are areas where Nitosols and Alisols with higher soil erodibility character(0.25)values are dominant.Hence,Slope gradient and length followed by soil erodibility factors were found to be the main factors of soil erosion.Thus,sustainable soil and water conservation practices should be adopted in steepest upper part of the study area by respecting and recognizing watershed logic,people and watershed potentials.
基金Supported by School of Graduate Studies through Aklilu LemmaInstitute of Pathobiology,Addis Ababa University(No:RDP/Py-014/09)
文摘Objective:To assess the distribution of ABO blood group and their relationship with Plasmodium falciparum(P.falciparum) malaria among febrile outpatients who sought medical attention at Dore Bafeno Health Center,Southern Ethiopia.Methods:A total of 269 febrile outpatients who visited Dore Bafeno Health Center,Southern Ethiopia,were examined for malaria and also tested for ABO blood groups in January 2010.The blood specimens were collected by finger pricking,stained with Geimsa,and examined microscopically.Positive cases of the parasitemia were counted.CareStart^(TM) Malaria PflPv Combo was also used to test the blood specimens for malaria.ABO blood groups were determined by agglutination test using ERYCLONE antisera.Data on socio-demographic characteristics and treatment status of the participants were also collected.Chi-square and ANOVA tests were used to assess the difference between frequencies and means,respectively.Results:Out of a total of 269 participants,178(66.2%) febrile patients were found to be infected with Plasmodium parasites,among which 146(54.3%),28(10.4%),and 4(1.5%) belonged to P.falciparum,P.vivax,and mixed infections,respectively.All febrile patients were also tested for ABO blood groups and 51.3%,23.5%,21.9%and 3.3%were found to be blood types of 0,A,B and AB,respectively.Both total malaria infection and P.falciparum infection showed significant association with blood types(P<0.05).The proportion of A or B but not 0 phenotypes was higher(P<0.05) in individuals with P.falciparum as compared with non-infected individuals.The chance of having P.falciparum infection in patients with blood groups A,B and AB was 2.5,2.5 and 3.3times more than individuals showing blood 0 phenotypes,respectively.The mean P.falciparum malaria parasitemia for blood groups A,B,AB,and 0 were 3 744/μ L,1 805/ μ L,5 331/μ L,and1 515/μ L,respectively(P<0.01).Conclusions:The present findings indicate that individuals of blood groups A,B and AB are more susceptible to P.falciparum infection as compared with individuals o
文摘Ethiopia has a mountainous landscape which can be divided into the Northwestern and Southeastern plateaus by the Main Ethiopian Rift and Afar Depression. Debre Sina area is located in Central Ethiopia along the escarpment where landslide problem is frequent due to steep slope, complex geology, rift tectonics, heavy rainfall and seismicity. In order to tackle this problem, preparing a landslide susceptibility map is very important. For this, GISbased frequency ratio(FR) and logistic regression(LR) models have been applied using landslide inventory and the nine landslide factors(i.e. lithology, land use, distance from river & fault, slope, aspect, elevation, curvature and annual rainfall). Database construction, weighting each factor classes or factors, preparing susceptibility map and validation were the major steps to be undertaken. Both models require a rasterized landslide inventory and landslide factor maps. The former was classified into training and validation landslides. Using FR model, weights for each factor classes were calculated and assigned so that all the weighted factor maps can be added to produce a landslide susceptibility map. In the case of LR model, the entire study area is firstly divided into landslide and non-landslide areas using the training landslides. Then, these areas are changed into landslide and non-landslide points so as to extract the FR maps of the nine landslide factors. Then a linear relationship is established between training landslides and landslide factors in SPSS. Based on this relationship, the final landslide susceptibility map is prepared using LR equation. The success-rate and prediction-rate of FR model were 74.8% and 73.5%, while in case of LR model these were 75.7% and 74.5% respectively. A close similarity in the prediction and validation rates showed that the model is acceptable. Accuracy of LR model is slightly better in predicting the landslide susceptibility of the area compared to FR model.
文摘Background Neonatal jaundice is a common condition characterized by a yellowish discoloration of the skin,conjunctiva,and sclera caused by elevated serum or plasma bilirubin levels during the newborn period.The condition is usually not dangerous,but it can progress to severe hyperbilirubinemia,which can lead to acute bilirubin encephalopathy and kernicterus,a bilirubin-induced neurological damage.Therefore,this study aimed to assess the pooled prevalence of neonatal jaundice and its determinants in Ethiopia.Methods Scopus,PubMed,Google Scholar,Embase,and CINAHL databases were searched for studies published between January 1,2010 and July 30,2021.A weighted DerSimonian Laird random-effects model was used to estimate the pooled prevalence of neonatal jaundice and its associated factors.The I2 was used to calculate the degree of heterogeneity.The funnel plot and Egger's regression test were used to assess publication bias.Results Totally 697 articles were generated from various databases,and the review included a total of eight articles.The pooled prevalence of neonatal jaundice was 30.96%[95%confidence interval(CI)16.61%–45.31%)]in Ethiopia.This review showed that prolonged labor[adjusted odd ratio(AOR)=3.39;95%CI 2.41–4.77),low birth weight(AOR=5.12;95%CI 3.11–8.72),birth asphyxia(AOR=3.75;95%CI 2.11–6.66),cephalohematoma(AOR=7.07;95%CI 2.72–18.38),ABO incompatibility(AOR=6.05;95%CI 2.95–12.42),Rhesus(RH)incompatibility(AOR=3.77;95%CI 2.04–6.96),male sex(AOR=4.53;95%CI 3.39–6.07),and neonatal sepsis(AOR=2.47;95%CI 1.49–4.08)were identified as a determining factor for neonatal jaundice in Ethiopia.Conclusions In low-and middle-income countries,neonatal jaundice is a significant healthcare burden,accounting for a significant portion of global childhood mortality and morbidity.However,some low-cost,effective,practical,and dependable solutions have been implemented.Prolonged labor,ABO incompatibility,RH incompatibility,birth asphyxia,neonatal sepsis,low birth weight,cephalohematoma,and male sex were
