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| 1 | Combustion synthesis, characterization and luminescence properties of barium aluminate phosphor显示文摘The blue-green emitting Eu2+ and Nd3+ doped polycrystalline barium aluminate(BaAl2O4:Eu2+,Nd3+) phosphor, was prepared by a solution-combustion method at 500 oC without a post-annealing process. The characteristic variation in the structural and luminescence properties of the as-prepared samples was evaluated with regards to a change in the Ba/Al molar ratio from 0.1:1 to 1.4:1. The morphologies and the phase structures of the products were characterized by scanning electron microscopy(SEM), transmission electron microscopy(TEM), X-ray diffraction(XRD) and X-ray photoelectron spectroscopy(XPS), while the optical properties were investigated using ultra-violet(UV) and photoluminescence(PL) spectroscopy, respectively. The XRD and TEM results revealed that the average crystallite size of the BaAl2O4:Eu2+,Nd3+ phosphor was about 70 nm. The broad-band UV-excited luminescence of the phosphors was observed at λmax=500 nm due to transitions from the 4f65d1 to the 4f7 configuration of the Eu2+ ion. The PL results indicated that the main peaks in the emission and excitation spectrum of phosphor particles slightly shifted to the short wavelength due to the changes in the crystal field due to the structure changes caused by the variation in the quantity of the Ba ions in the host lattice. | A.H. Wako F.B Dejene H.C Swart | 2014 | Journal of Rare Earths2014，32，9： | 4 |
| 2 | Phenotypic diversity in Ethiopian durum wheat(Triticum turgidum var.durum)landraces显示文摘The phenotypic diversity of 274 Ethiopian durum wheat accessions was analyzed, taking their geographic origins into account. The aim was to assess the extent and patterns of agronomically important phenotypic variation across districts of origin and altitude classes for major qualitative traits using diversity index and multivariate methods. Eight qualitative and three quantitative traits were scored for 2740 plants and analyzed for diversity. The Shannon–Weaver diversity(H′) index was used to estimate phenotypic diversity. The estimated H′ ranged from monomorphic for glume hairiness to highly polymorphic for other traits. The highest(0.86) H′ was obtained for seed degree of shriveling, possibly indicating the differential responses of the genotypes to water deficit during later growth stages. With respect to district of origin, the highest(0.72) and lowest(0.44) H′ values were obtained for the Bale and SNNP districts, respectively. With respect to altitude, the highest(0.76) and lowest(0.62) H′ values were recorded for altitudes 1600–2000and > 3000 m above sea levels, respectively. Principal components analysis explained substantial variation contributed by district of origin and altitude range. Genotypes were clustered into three groups by districts of origin and altitude class, with relatively strong bootstrap values of 57 and 62 for the former and latter, respectively. It could be concluded that Ethiopian durum wheat landraces are very diverse both within and among districts of origin and altitude classes. This wealth of genetic diversity should be exploited for wheat improvement of yield and for resistance to biotic and abiotic stresses, particularly terminal drought. | Dejene K.Mengistu Afeworki Y.Kiros Mario E.Pè | 2015 | The Crop Journal2015，3，3： | 3 |
| 3 | IL-1β limits the extent of human 6-sulfo LacNAc dendritic cell (slanDC)-mediated NK cell activation and regulates CD95-induced apoptosis显示文摘To function optimally,human blood natural killer(NK)cells need to communicate with other immune cells.Previously,it has been shown that NK cells communicate with 6-sulfo LacNAc dendritic cells(slanDCs),which are able to stimulate NK cells in vitro.In this study,we investigated how slanDCs regulate the level of NK cell activation.The secretion of interleukin(IL)-1βby slanDCs during coculture with NK cells increased as a result of signaling via intercellular adhesion molecule-1 on slanDCs following its interaction with lymphocyte functionassociated antigen-1 on NK cells.IL-1βinduced the expression of Fas receptor(CD95)on NK cells.The binding of Fas ligand(CD178)to CD95 induced the apoptosis of activated NK cells.Moreover,IL-1βalso induced increased cyclooxygenase-2 expression in slanDCs,which in turn enabled the cells to secrete prostaglandin(PG)-E2.Consequently,PGE2 acted as a suppressing agent,tuning down the activation level of NK cells.In summary,IL-1βlimits the level of NK cell activation by inducing apoptosis and suppression as a homeostatic regulatory function. | Dejene Milkessa Tufa Fareed Ahmad Debanjana Chatterjee Gerrit Ahrenstorf Reinhold Ernst Schmidt Roland Jacobs | 2017 | Cellular & Molecular Immunology2017，14，12： | 2 |
| 4 | Land suitability analysis for maize production using geospatial technologies in the Didessa watershed,Ethiopia显示文摘Physical land suitability assessment is a prerequisite for enhancing yield production and enables the agricultural communities to use the right place for the right crops.Maize is one of stable one food crops of Ethiopia and cultivated in three agroecological zones:highland,midland and lowlands.Despite these facts,maize yield is very low due to a lack of knowledge and information gaps on land suitability.Physical land suitability for maize cultivation is essential to minimize the problem of food security.The present study aims to identify the potential land suitability for maize production in the Didessa watershed,Western Ethiopia using Multi-Criteria Evaluation(MCE)and geospatial technologies.Land use land cover(LULC)change,climate,topography,soil,and infrastructure facilities were considered for maize land suitability assessment.The MCE based pairwise comparison matrix was applied to estimate land suitability for maize crop cultivation.The results showed that,about 977.7 km^(2)(14.1%)is highly suitable,4794.9 km^(2)(69.1%)is moderately suitable while 1118.8 km^(2)(16.1%),and 51.5 km^(2)(0.7%)of the study area were categorized under marginally and not suitable for maize production,respectively.This research provides crucial information for decision making organs and the farming community to utilize potential areas for maize cultivation. | Mitiku Badasa Moisa Firdissa Sadeta Tiye Indale Niguse Dejene Dessalegn Obsi Gemeda | 2022 | Artificial Intelligence in Agriculture2022，，1： | 2 |
| 5 | Placental microRNA expression in pregnancies complicated by preeclampsia显示文摘 | Daniel A. Enquobahrie Dejene F. Abetew Tanya K. Sorensen David Willoughby Kumaravel Chidambaram Michelle A. Williams | 2011 | American Journal of Obstetrics and Gynecology2011，，2： | 1 |
| 6 | Impregnation and Characterization of High Performance Extraction Columns for Separation of Metal Ions显示文摘 | Dejene Kifle Grethe Wibetoe Morten Fr?seth Jonas Bigelius | 2013 | Solvent Extraction and Ion Exchange2013，，6： | 1 |
| 7 | Livestock Feed Marketing in Ethiopia: Challenges and Opportunities for Livestock Development显示文摘 | Mesfin Dejene Seyoum Bediye Dawit Alemu Getu Kitaw Aemiro Kehaliw Getnet Assefa Getaw Tadesse | 2014 | Journal of Agricultural Science and Technology(A)2014，4，2： | 1 |
| 8 | Synthesis and characterization of ZnO nanoparticles using polyethylene gly- col (PEG) 显示文摘 | Tshabalala M A Dejene B F Swart H C | 2012 | Physica B: Condens Matter2012，407，10： | 1 |
| 9 | Seroepidemiology of mea-sles in Addis Ababa,Ethiopia :implications for control through vac-cination显示文摘 | Enquseiassie F Ayele W Dejene A | 2003 | Epidemiol Infect2003，130，3： | 1 |
| 10 | Electrical, optical and structural properties of pure and gold-coated VO2 thin films on quartz substrate显示文摘 | Dejene F B Ocaya R O | 2010 | Curr Appl Phys2010，10，2： | 1 |
| 11 | Impact of climate change on biodiversity and associated key ecosystem services in Africa:a systematic review显示文摘Introduction:Biodiversity and biodiversity-based ecosystems services are intrinsically dependent on the climate.During the twentieth century,climate change has posed major threats to biodiversity in Africa,and impacts are expected to increase as climate change continues and perhaps even accelerates.Outcomes:Our review shows that the multiple components of climate change are projected to affect all levels of biodiversity,from genes over species to biome level.Loss of biodiversity as a result of climate change can alter the structures and functions of African ecological systems.As a result,the provision of biodiversity-based ecosystem services and the wellbeing of people that rely on these services are being modified.Of particular concerns are“tipping points”where the exceedance of ecosystem thresholds will possibly lead to irreversible shifts of the structure of ecosystems and their services.In recent years,climate prediction models have portended continued warming and more frequent extreme weather events across the region.Such weather-related disturbances such as El Niño will place a premium on biodiversity and biodiversity-based ecosystem services that people rely on.Conclusion:As biodiversity underlies all goods and services provided by ecosystems that are crucial for human survival and well-being,this paper synthesizes and discusses observed and anticipated impacts of climate change on biodiversity and biodiversity-based ecosystem service provision and livelihoods,and what strategies might be employed to decrease current and future risks on the well-being of human in Africa. | Dejene W.Sintayehu | 2018 | Ecosystem Health and Sustainability2018，4，9： | 1 |
| 12 | The Structural and Material Properties of CuInSe2 and Cu(In,Ga)Se2 Prepared by Selenization of Stacks of Metal and Compound Precursors by Se Vapor for Solar Cell Applications显示文摘 | Dejene F B | 2009 | Solar Energy Materials and Solar Cells2009，93，5： | 1 |
| 13 | Stress-induced dissociations between intracellular calcium signaling and insulin secretion in pancreatic islets显示文摘 | QURESHI FM DEJENE EA CORBIN KL | 2015 | Cell Calcium2015，57，56： | 1 |
| 14 | Electrical, optical and structural properties of pure and gold-coated VO2 thin films on quartz substrate显示文摘 | DEJENE F B OCAYA R O | 2010 | Current Applied Physics2010，10，3： | 1 |
| 15 | Attitude and social conse- quences of tuberculosis in Addis Ababa, Ethiopia显示文摘 | Gelaw M Genebo T Dejene A | 2001 | East African Med J2001，78，7： | 1 |
| 16 | Growth performance and gum arabic production of Acacia senegal in northwest lowlands of Ethiopia显示文摘Despite the wide distribution of natural stands of Acacia senegal in Ethiopia, commercial exploitation of gum arabic is constrained by lack of tapping and development techniques. We evaluated the gum arabic yield from natural stands of A. senegal and the growth of 6 provenances in different parts of the country. For the gum yield evaluation from natural stands, four tapping positions and three tapping seasons were tested in a factorial RCB design. The second experiment in Metema evaluated survival and growth of six provenances. A. senegal trees in natural stands respond well to tapping if tapped during the appropriate season and at the correct position on the tree. The mean gum yield did not vary significantly by tapping season (p=0.63). Higher mean yield was, however, collected from trees tapped in October (96 g·tree-1 per two harvests). The mean yield differed significantly (p=0.009) between the tapping positions. Mean separation (α=0.05) shows that trees tapped at mid stem gave higher yield (160 g·tree-1 per two harvests). The interaction effect of tapping season and position was not significant. Higher mean yield ((70 ± 112) g·tree-1 ) was recorded in mid October-mid stem in two harvests. The second experiment indicated statistically significant difference in mean survival (p=0.0298), height (p=0.000) and root collar diameter (RCD), (p=0.012) between the six provenances. Highest survival, height and root collar diameter growth was observed from Abderafi provenance (100%, (148±11) cm, (38±11) mm, respectively). We recommend October and mid-stem and branches as appropriate tapping season and position. We recommend planting of the Abderafi provenance for the study area due to its superior growth and survival. Our study contributes to the proper selection of provenances for plantation development and improved tapping technology for better production of gum arabic in the country. | Asmamaw Alemu Zewdu Yilma Abeje Eshete Tatek Dejene | 2013 | Journal of Forestry Research2013，24，3： | 1 |
| 17 | The effect of rate of hydrolysis on structural and optical properties of the TiO2nanoparticles prepared by a sol-gel method显示文摘 | DEJENE F B ONANI M O TARUS P K | 2015 | Physica B2015，480，： | 1 |
| 18 | Stress-in- duced dissociations between intracellular calcium signaling and insulin secretion in pancreatic islets显示文摘 | QURESHI F M DEJENE E A CORBIN K L | 2015 | Ceil Calcium2015，57，56： | 1 |
| 19 | Photoluminescence properties of Ce3+-doped SrAl2O4 prepared using the solution combustion method显示文摘 | FOKA K E DEJENE F B SWART H C | 2014 | Physica B:Condensed Matter2014，439，15： | 1 |
| 20 | The structm'al and material properties of CulnSe2 and Cu (ln,Ga)Se2 plpared by selenization of stacks of metal and compound precursors by Se vapor for solar cell applications 显示文摘 | DEJENE F B | 2009 | Solar Energy Materials & Solar Cells2009，93，5： | 1 |
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