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| 1 | 喷射FRP加固震损钢筋混凝土柱抗震性能试验显示文摘通过12组72件喷射纤维/树脂复合材料(FRP)试样的拉伸强度试验,研究了纤维种类、树脂基体材料、纤维体积分数、纤维混杂比及纤维长度等因素对喷射FRP拉伸强度、弹性模量和断裂伸长率等性能的影响。通过8根钢筋混凝土(RC)柱试件的拟静力试验,研究了喷射玄武岩纤维/树脂复合材料(BFRP)和混杂玄武岩-碳纤维/树脂复合材料(BF-CFRP)加固震损RC柱的抗震性能,分析了喷射FRP层厚度、纤维混杂比、柱预损程度和柱轴压比等对加固试件的极限承载力、抗侧变形能力、刚度退化特征和滞回特性的影响。结果表明:玻璃纤维与乙烯基酯树脂基体的协同工作性能最优,而玄武岩纤维具有耐久性高、延性好、与乙烯基酯树脂基体协同工作性能好等优良性能,可以作为玻璃纤维的良好替代品;玄武岩纤维混杂少量比例的碳纤维作为树脂基体增强材料,可以有效提高喷射FRP的拉伸强度和变形性能;震损RC柱经喷射FRP加固后,可以基本恢复其震损前设计极限承载力,并有效提高其延性和耗能能力。该加固方法可以对地震区已震损RC柱进行快速加固,有效防止整体结构在余震中发生倒塌等严重破坏。 | 谷倩 董格 GETAHUNE Bitewlgn Mekonnen 王翔 | 2016 | 复合材料学报2016，33，5： | 6 |
| 2 | THREE DIMENSIONAL NUMERICAL MODELLING OF FLOW AND SEDIMENT TRANSPORT IN RIVERS显示文摘The 3D numerical model, ECOMSED (open source code), was used to simulate flow and sediment transport in rivers. The model has a long history of successful applications to oceanic, coastal and estuarine waters. Improvements in the advection scheme, treatment of river roughness parameterization and shear stress partitioning were necessary to reproduce realistic and comparable results in a river application. To account for the dynamics of the mobile bed boundary, a model for the bed load transport was included in the code. The model reproduced observed secondary currents, bed shear stress distribution and erosion-deposition patterns on a curved channel. The model also successfully predicted the general flow patterns and sediment transport characteristics of a 1-km long reach of the River Klar?lven, located in the north of the county of V?rmland, Sweden. | M. A. MEKONNEN B. DARGAHI | 2007 | International Journal of Sediment Research2007，22，3： | 4 |
| 3 | Wind Power Fluctuation Compensation by Variable Speed Pumped Storage Plants in Grid Integrated System:Frequency Spectrum Analysis显示文摘Electrical power generation from wind technology is the most rapidly growing technology due to its ample characteristics.Nevertheless,because of its stochastic feature,it has the unnecessary impact on the operations and stability of the power grid system.The fluctuation of the grid frequency problem,for example,is more pronounced.The fluctuation of the frequency in turn impacts even the collapse of the power system.To minimize such problems,a droop-vector control strategy applied on a doubly-fed induction machine based(DFIM)variable speed pumped storage(VSPS)system is proposed in this paper.This method is should be used as a wind power fluctuation compensation solution in the wind farm-grid integration system.The system model is made on the basis of the technique called a phasor model.The frequency spectrum analysis approach is used in the VSPS plant for determining the dynamic performances of the grid in case of contingencies including wind power fluctuation compensation.The software platform MATLAB/Simulink is used for verifying the performance of the proposed system.The results show that the method of the frequency spectrum analysis technique is effective for determining the wind power fluctuation and stability requirements in large power networks.The control strategy proposed in this paper implementing the VSC-DFIM based VSPS plant integrated with the power gird and wind farm network achieves a well-controlled power flow and stable grid frequency with the deviations being in acceptable ranges. | Minxiao Han Girmaw Teshager Bitew Sifrash Amogne Mekonnen Wenli Yan | 2021 | CSEE Journal of Power and Energy Systems2021，7，2： | 3 |
| 4 | In-vitro antimicrobial activity screening of some ethnoveterinary medicinal plants traditionally used against mastitis,wound and gastrointestinal tract complication in Tigray Region,Ethiopia显示文摘Objective:To screen the antibacterial activity of nine ethnoveterinary plants traditionally used for the treatment of mastitis,wound and gastrointestinal complications.Methods:Hydroalcoholic exctracts of medicinal plants namely,Achyranthes aspera(A.aspera) L.(Family Asparagaceae),Ficus caria(F.caria)(Family Moraceae).Malvi parviflora(M.parviflora)(Family Malvaceae),Vernonia species(V.species) docal name Alakit.Family Asteraceae),Solatium hastifolium(S.hastifolium)(Family Solanaceae),Calpurinia aurea(C.aurea)(Ait) Benth(Family Fabaceae),Nicotiana tabacum(N.tabacum) L.(Family Solanaceae),Ziziphus spina-christi(Z.spina-christi)(Family Rhamnaceae).Croton macroslachys(C.macrostachys)(Family Fuphorhiaceae).were screened against clinical bacterial isolates of veterinary importance from October 2007 to April2009.The antibacterial activity was tested using disc diffusion at two concentrations(200 mg/mL and 100 mg/mL) and broth dilution methods using 70%methanol macerated leal extracts.Results:With the exception ol S.hastifolium all plant extracts exhibited antibacterial activity.Among the medicinal plants tested C.aurea.C.macrostachyus,A.aspera,N.tabacum and vcrnonia species(Alakit) showed the most promising antimicrobial properties.Conclusions:It can be concluded that many of the tested plants have antibacterial activity and supports the traditional usage of the plants for mastitis,wound and gastrointestinal complications treatment.Further studies into their toxicity and phytochemistry is advocated. | Shewit Kalayou Mekonnen Haileselassie Gebremedhin Gebre-egziabher Tsegay Tiku'e Samson Sahle Habtamu Taddele Mussie Ghezu | 2012 | Asian Pacific Journal of Tropical Biomedicine2012，2，7： | 3 |
| 5 | Treatment outcomes of tuberculosis patients under directly observed treatment short-course at Debre Tabor General Hospital,northwest Ethiopia:nine-years retrospective study显示文摘Background:Data regarding tuberculosis(TB)treatment outcomes,proportion of TB/HIV co-infection and associated factors have been released at different TB treatment facilities in Ethiopia and elsewhere in the world as part of the auditing and surveillance service.However,these data are missing for the TB clinic offering directly observed treatment short-course(DOTs)at Debre Tabor General Hospital(DTGH).Methods:The authors analysed the records of 985 TB patients registered at the DTGH from September 2008 to December 2016.Data on patients’sex,age,type of TB,and treatment outcomes were extracted from the TB treatment registration logbook.The treatment outcome of patients was categorized according to the National TB and Leprosy Control Program guidelines:cured,treatment completed,treatment failed,died,and not evaluated(transferred out and unknown cases).Results:Around half of the registered patients were males(516,52.4%).In terms of TB types,381(38.7%),241(24.5%),and 363(36.9%)patients had smear-negative pulmonary TB,smear-positive pulmonary TB,and extra pulmonary TB,respectively.Six hundred and seventy-two patients(90.1%)had successful treatment outcomes(cured and treatment completed),while 74 patients(9.9%)had unsuccessful treatment outcomes(death and treatment failure).TB treatment outcome was not associated with age,sex,type and history of TB,or co-infection with HIV(P>0.05).The proportion of TB/HIV co-infection was at 24.2%,and these were found to be significantly associated with the age groups of 25-34,35-44 and≥65 years:(aOR:0.44;95%CI:0.25-0.8),(aOR:0.39;95%CI:0.20-0.70),(aOR:4.2;95%CI:1.30-12.9),respectively.Conclusions:The proportion of patients with successful treatment outcomes was above the World Health Organization target set for Millennium Development Goal of 85%and in line with that of the global milestone target set at>90%for 2025.Relatively higher proportions of transfer-out cases were recorded in the present study.Similarly,the proportion of TB/HIV co-infection cases was much higher than the national average of 8%.Thus,the health facility under study should develop strategies to record the final treatment outcome of transfer-out cases.In addition,strategies to reduce the burden of TB/HIV co-infection should be strengthened. | Seble Worku Awoke Derbie Daniel Mekonnen Fantahun Biadglegne | 2018 | Infectious Diseases of Poverty2018，7，1： | 3 |
| 6 | A global and high-resolution assessment of the green, blue and grey water footprint of wheat显示文摘 | Mekonnen M. M. Hoekstra A. Y | 2010 | Hydrology and Earth System Sciences2010，，121： | 2 |
| 7 | Myocardial Bridging: Contemporary Understanding of Pathophysiology with Implications for Diagnostic and Therapeutic Strategies显示文摘 | Michel T. Corban Olivia Y. Hung Parham Eshtehardi Emad Rasoul-Arzrumly Michael McDaniel Girum Mekonnen Lucas H. Timmins Jerre Lutz Robert A. Guyton Habib Samady | 2014 | Journal of the American College of Cardiology2014，，： | 2 |
| 8 | Ethiopian vegetation types,climate and topography显示文摘Ethiopia is land of geographical contrasts with elevations that range from 125 m below sea level in the Danakil Depression to 4533 m above sea level in the Semien Mountains,a world heritage site.The diverse climate of various ecological regions of the country has driven the establishment of diverse vegetation,which range from Afroalpine vegetation in the mountains to the arid and semi-arid vegetation type in the lowlands.The formation of Ethiopian vegetation is highly connected to the climate and geological history of the country.Highland uplift and rift formation due to volcanic forces formed novel habitats with different topography and climatic conditions that have ultimately become drivers for vegetation diversification.Due to Ethiopia's connection with the temperate biome in the north and the Arabian Peninsula during the dry glacial period,the biotic assemblage of Ethiopian highlands consists of both Afrotropical and palearctic biota.In general,eight distinct vegetation types have been identified in Ethiopia,based mainly on elevation and climate gradients.These vegetation types host their own unique species,but also share several common species.Some of the vegetation types are identified as centers of endemism and have subsequently been identified globally as the East African Afromontane hotspot.Ethiopia is biologically rich,with more than 6500 vascular plant species.Of these species,12%are endemic mainly due to geographical isolation and unique climatic conditions.However,researchers have yet to extensively investigate the ecology,phenology,as well as the evolutionary,genetics,and conservation status of Ethiopian vegetations at community and species level over space and time.This lack of research is a barrier to achieving the goal of zero global plant extinctions.Taxa extinction risk assessment has not been extensively carried out for majority of Ethiopian species.Detailed research is needed to explore how vegetation and species respond to rapidly growing environmental change.Currently,human-induced climate change and habitat fragmentation are severely threatening the country's biodiversity,and the consequences of these effects have not been studied at large.Furthermore,we still lack scientific evidence on how micro-and macro-ecological and evolutionary processes have been shaping vegetation structures in this climatically,topographically,and geologically diverse country.These gaps in our knowledge represent an opportunity for ecologists,geneticists,evolutionary biologists,conservation biologists,and other experts to investigate the biodiversity status and the complex ecological processes involved in structuring vegetation dynamics so as to help take effective conservation actions. | Mengesha Asefa Min Cao Yunyun He Ewuketu Mekonnen Xiaoyang Song Jie Yang | 2020 | Plant Diversity2020，42，4： | 2 |
| 9 | Evaluation of berries of Phytolacca dodecandra for growth inhibition of Histoplasma capsulatum var.farciminosum and treatment of cases of epizootic lymphangitis in Ethiopia显示文摘Objective:To evaluate the berries of Phytolacca dodecundra(P.dodecandra) for its effect on Histoplasma cupsulatum var.farciminosum(HCF) and for the treatment of cases of epizootic lymphangitis(ELi.Methods:Samples were collected from un-ruptured nodules of cases of EL at Debre Zeit and Akaki(central Ethiopia).Mycologieal culture and isolation of HCF were performed at the Akliln Lemma Institute of Pathobiology.Phytochemical screening was done for n-butanol extract of P.dodecandra to delect alkaloids,saponins,phenolic compounds and flavonoids.The minimum inhibitory concentrations(MICs) and minimum fungicidal concentrations(MFCs) ol aqueous and n-butanol extracts of P.dodecandra against FICF were determined by agar dilution assay.For the in vivo trial.5%simple ointment was prepared from n-butanol extract and applied topically to 24(twelve early and twelve moderate) cases of F.L.Results:Phytochemical screening showed that n-butanol extract ol P.dodecandra was positive lor alkaloids.saponins and phenolic compounds but negative for flavonoids.The MFCs of n-butanol and aqueous extracts of P.dodecandra were(0.039%-0.078%) and(0.625%-1.250%),respectively.The MFCs of n-butanol and aqueous extracts of P.dodecandra were(0.078%t-0.156%)and(1.250%-2.500%),respectively.The MIC and MFC of ketoconazole(positive control) was(1.200×10^(-5)%-2.500×10^(-5)%) and(5.000× 10^(-5)%-1.000×10^(-4)%),respectively while growth was observed on free medium(negative control).From the total of 24 treated cases of EL,14(58.3%) responded lo treatment;however,10(41.7%) did not respond to treatment.There was no significant difference in the degree of response to treatment between early and moderate cases(χ~2=0.086:P=0.408.Conclusions:It can be concluded that n-butanol extract of P.dodecandra demonstrates antifungal effects while the aqueous extract shows no antifungal activity. | Negesse Mekonnen Eyasu Makonnen Nigatu Aklilu Gobena Ameni | 2012 | Asian Pacific Journal of Tropical Biomedicine2012，2，7： | 2 |
| 10 | Molecular epidemiology of Giardia duodenalis infection in humans in Southern Ethiopia:a triosephosphate isomerase gene-targeted analysis显示文摘Background:Giardia duodenalis is a species complex consisting of multiple genetically distinct assemblages.The species imposes a major public health crisis on developing countries.However,the molecular diversity,transmission dynamics and risk factors of the species in these countries are indeterminate.This study was conducted to determine the molecular epidemiology of G.duodenalis infection in asymptomatic individuals in Southern Ethiopia.Methods:From March to June 2014,fresh stool samples were collected from 590 randomly selected individuals.Socio-demographic data were gathered using a pre-tested structured questionnaire.The genotyping was done using triosephosphate isomerase gene-based nested polymerase chain reaction and DNA sequencing.The genetic identity and relatedness of isolates were determined using the basic local alignment search tool and phylogenetic analysis.Risk factors associated with G.duodenalis infection were analysed using binary and multinomial logistic regression models.Results:The results showed that 18.1%(92/509)of the study subjects were infected by G.duodenalis.Among the isolates,35.9%(33/92)and 21.7%(20/92)were sub-typed into assemblages A and B,respectively,whereas 42.4%(39/92)showed mixed infections of A and B.Most of the assemblage A isolates(94%,31/33)were 100%identical to sequences registered in GenBank,of which the majority belonged to sub-assemblage AII.However,the high genetic variability and frequency of double peaks made sub-genotyping of assemblage B more problematic and only 20%(4/20)of the isolates matched 100%with the sequences.The risk factors of age(P=0.032)and type of drinking water source(P=0.003)both showed a significant association with the occurrence G.duodenalis infection.Conclusions:This study established the endemicity of G.duodenalis in Southern Ethiopia.Infection with assemblage A was more frequent than with assemblage B,and the rate of infection was higher in children and in municipal/tap and open spring water consumers than the other groups.Sub-typing of assemblage B and determining the origin of double peaks were challenging.The present study confirms the need for further inclusive studies to be conducted focusing on sub-types of assemblage B and the origin of heterogeneity. | Mengistu Damitie Zeleke Mekonnen Tadesse Getahun Dante Santiago Luc Leyns | 2018 | Infectious Diseases of Poverty2018，7，1： | 2 |
| 11 | Re-examining project appraisal and control:developing a focus on wealth creation 显示文摘 | Mehari Mekonnen Akalu | 2001 | International Journal of Project Management2001，19，： | 1 |
| 12 | The Green,Blue and Grey Water Footprint of Crops and Derived Crop Prod- ucts显示文摘 | MEKONNEN MM HOEKSTRA A Y | 2011 | Hydrology and Earth System Sciences2011，15，5： | 1 |
| 13 | High helminthic co-infection in tuberculosis patients with undernutritional status in northeastern Ethiopia显示文摘Background:Tuberculosis and parasitosis are the widely distributed diseases in Ethiopia with the leading cause of mortality and morbidity,respectively.There has been no information on the status of co-infections of tuberculosis and parasitosis in Oromia Zone of Amhara Region and South Wollo,Ethiopia.Hence,this study primarily focuses on determining the status of tuberculosis and parasitosis co-infections and associated factors.Methods:The study was conducted in Oromia Special Zone of the Amhara Regional State and South Wollo Zone,northeastern Ethiopia from April 2015 to January 2017.Tuberculosis cases confirmed by health personnel at the health institutions were the source of the study sample.In a cross-sectional study 384 smear positive pulmonary and extra-pulmonary tuberculosis cases were recruited.Faecal specimens provided by the study participants were examined for parasitic co-infections using direct saline microscopic test,Kato-Katz and concentration techniques.Nutritional status was determined using body mass index and mid-upper arm circumferences.Data were analyzed using descriptive statistical methods and Pearson chi-square.Results:Tuberculosis and parasitosis co-infection prevalence was 10.8%,and the proportion of intestinal helminths accounted for 9.7%while intestinal protozoa accounted for 1.9%.Cases with single parasitic infection was 89.3%among co-infected individuals.Co-infection of both disease was not significantly associated with gender and age(P>0.05).The prevalence of undernutrition was 58.6%as determined using body mass index and 73.0%as determined using mid-upper arm circumference with no significant association with gender.Among all forms of tuberculosis cases(384)screened for the study,the bacterial positivity was relatively more common in males(55.5%)than females(44.5%).Tuberculosis lymphadenitis was found to be the most prevalent(85.9%)form of extrapulmonary tuberculosis with cervical adenopathy(75.3%)being the commonly existing disease.Conclusions:The rate of helminthic co-infection is predominantly high than that of intestinal protozoa.Single parasitic co-infection was more common than double or multiple co-infections.Both body mass index and midupper arm circumference anthropometric parameters revealed greater risk of undernutrition in tuberculosis patients.Thus,screening and prompt treatment of parasites in tuberculosis patients and a support of nutritional supplementation for malnourished tuberculosis patients should be further studied which might enhance the disease treatment and minimize the risk of its complexity. | Fikru Gashaw Samuel Bekele Yalemtsehay Mekonnen Girmay Medhin Gobena Ameni Berhanu Erko | 2019 | Infectious Diseases of Poverty2019，8，5： | 1 |
| 14 | The external water footprint of the Netherlands: Geographically-explicit quantification and impact assessment显示文摘 | Van Oel P R Mekonnen M M Hoekstra A Y | 2009 | Ecological Econom- ics2009，69，1： | 1 |
| 15 | Reply to Ridoutt and Huang:From water footprint assessment to policy 显示文摘 | Hoekstra A Y Mekonnen M M | 2012 | Proceedings of the National Academy of Sciences2012，109，22： | 1 |
| 16 | Measures of gene expression in sputum cells can identify TH2-high and TH2-low subtypes ofasthma显示文摘 | Peters MC Mekonnen ZK Yuan S | 2014 | J Allergy Clin Immunol2014，133，2： | 1 |
| 17 | Field trials on the repellent activity of four plant products against mainly Mansonia population in Western Ethiopia显示文摘 | Hadis M Lulu M Mekonnen Y | 2003 | Phytother Res2003，17，3： | 1 |
| 18 | A global and high-resolution assessment of the green,blue and grey water footprint of wheat显示文摘 | MEKONNEN M M HOEKSTRA A Y | 2010 | Hydrology and Earth System Sciences2010，14，： | 1 |
| 19 | The blue water footprint of electricity from hydropower显示文摘 | MEKONNEN M M HOEKSTRA A Y | 2012 | Hydrology and Earth Sys- tem Sciences2012，16，： | 1 |
| 20 | The green, blue and grey water footprint of crops and derived crop products显示文摘 | MEKONNEN M M HOEKSTRA A Y | 2011 | Hydrology and Earth System Sciences2011，15，： | 1 |
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