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Testing a passive tracking index for monitoring the endangered ethiopian wolf

Integrative Zoology 2009年第2期4卷 172-178页

作者： Paul EVANGELISTA Richard ENGEMAN Lucy TALLENTS Natural Resource Ecology Laboratory Colorado State UniversityFort CollinsColoradoUSA National wildlife Research Center Fort CollinsColoradoUSA ethiopian Wolf conservation Programme Wildlife Conservation Research UnitOxford UniversityUK

The endangered ethiopian wolf is considered the rarest canid in *** species faces many threats and is particularly vulnerable to diseases such as rabies.A simple,low-technology means to monitor populations would greatly facilitate conservation efforts,through early detection of population changes and behavior,and signaling a need for *** tested a passive tracking index methodology,which has been a valuable tool for indexing canids and other species around the *** method uses counts of track intrusions into plots placed in the animals’routes of travel as the basis for calculating an *** for other species,for which the placement of tracking plots on dirt roads has been extremely successful,we found in our first trial that this approach did not adequately intersect the wolves’activity *** low vegetation associated with Afro-alpine habitats offered little benefit for the wolves to travel ***,in our second trial among molerat colonies,a focus of wolf foraging activity,we found plot placement on molerat mounds was efficient for collecting ethiopian wolf plot intrusions for index *** plot placement method coupled with the passive tracking index calculations might offer resource managers a cost efficient tool that requires minimal equipment to monitor ethiopian wolf populations on the Sanetti Plateau and other Afro-alpine *** placement on roads in other ethiopian wolf habitats where cross-country travel is more difficult might still be a viable means to collect track data,but would require further testing.

关键词： endangered species population abundance population monitoring Simien fox Simien jackal.

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Effect of Vachellia tortilis on understory vegetation,herbaceous biomass and soil nutrients along a grazing gradient in a semi-arid African savanna

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Journal of Forestry Research 2018年第6期29卷 1601-1609页

作者： Temesgen Yadeta Elmar Veenendaal Karle Sykora Zewdu K.Tessema Addisu Asefa Plant Ecology and Nature conservation Group Centre for Ecosystem StudiesWageningen UniversityDroevendaalsesteeg 3a6708PB WageningenThe Netherlands Rangeland Ecology and Biodiversity Program College of Agriculture and Environmental SciencesHaramaya UniversityPO Box 138Dire DawaEthiopia ethiopian wildlife conservation authority PO Box 386Addis AbabaEthiopia

The spatial pattern and abundance of herbaceous vegetation in semi-arid savannas are dictated by a complex and dynamic interaction between trees and grasses. Scattered trees alter the composition and spatial distribution of herbaceous vegetation under their canopies. Therefore, we studied the effect of Vachellia tortilis on herbaceous vegetation composition, biomass and basal area, and soil nutrients on sites with varying grazing intensities in the central rift valley of Ethiopia. Data were collected on species composition, cover and biomass of herbs and grasses, and soil moisture and nutrient contents under light,medium, and heavy grazing pressures, both under the inside and outside of V. tortilis canopies. Species richness was similar in both locations but decreased with increased grazing. Only the overall biomass and herb cover were significantly greater under the canopy than outside, and overall biomass showed significant unchanging decline with increased grazing. However, vegetation cover was significantly greater on moderately grazed sites compared to low and heavily grazed sites. All soil variables were significantly higher under V. tortilis canopies than *** findings suggest that V. tortilis has more effect on composition and diversity of herbaceous vegetation than on species richness, and that V. tortilis promotes the herbaceous layer biomass by reducing soil moisture loss and increasing soil fertility under the inside than outside the canopies. Therefore, we suggest that management practices should be directed on reducing pressure on V. tortilis by regulating grazing. Low to moderate grazing levels(i.e., a stocking rate less than 39.6 TLU ha-1yr-1) seems to be tolerable to ensure sustainable conservation of the species in the study area in particular and in semi-arid savannas in general.

关键词： Basal area cover Grazing pressure Inside/outside canopy Soil moisture

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Opportunities for New Biorefinery Products from ethiopian Ginning Industry By-products:Current Status and Prospects

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Journal of Bioresources and Bioproducts 2021年第3期6卷 195-214页

作者： Amare Abuhay Wassie Mengie Tamrat Tesfaye Gemeda Gebino Million Ayele Adane Haile Derseh Yillie Birorefinery Research Centre Ethiopian Institute of Textile and Fashion TechnologyBahir Dar UniversityBahir DarEthiopia

The global demand for textile products is rapidly increasing due to population growth,rising living standards,economic development,and fast fashion *** growth and transformation plan(GTP)gives high priorities for the textile and apparel sectors to transform its agriculturally led economy to an industrial-based *** achieve this,the number of tex-tile and apparel industries is rapidly ***,the rapid growth in textile industry is generating mountains and mountains of *** this review,possible applications of cotton stalk and cotton ginning waste in a variety of technologies and products are discussed in ethiopian *** finding of this study shows that ethiopian current cotton cultivating area is about 80000 hm^(2),even though the country has a potential of about 3000810 hm^(2) land for cotton *** the current cultivated area,more than 240000 t of cotton stalk and 9240 t of cotton ginning trash have been generated as a *** only a very little portion of the cotton stalk is being used as a raw fuel for household purposes and a small portion of cotton ginning trash is used for animal ***,these underutilized lignocellulosic biomasses can be used as raw materials for producing different high-value biomaterials and thus country can perceive an economic and environmental benefit.A closer look at the structure and composition of the by-products shows that the whole part of cotton stalk and ginning waste can be used as a source of cellulose which can be exploited for conversion into a number of high-value ***,conversion of the waste into valuable products can make cotton stalk and ginning by-products an attractive raw material for the production of high value bio-products.

关键词： Cotton stalk Cotton ginning waste Biobased materials Biorefinery Waste utilization

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Variation in seed traits and seedling vigour of Cordia africana *** in Ethiopia

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Journal of Forestry Research 2017年第5期28卷 925-934页

作者： Abayneh Derero Genene Tesfaye Zewdie Woldemariam ethiopian Environment and Forest Research Institute

Cordia africana is a very important indigenous tree species for timber and other products and services in Ethiopia. Seed traits and seedling vigour of seeds from 12 provenances of the species were compared. Mean seed mass for each provenance was assessed for 1000 seeds in 10 replications, and seed length and width were measured for 100 seeds in four replications per provenance. Germination was assessed in a glasshouse taking 400 seeds from each provenance. Root collar diameter and height of 440 seedlings grown in a nursery for 290 days in Addis Ababa were measured. Seed length, seed width, seed mass, and shoot height and root collar diameter of seedlings showed significant differences (P < 0.001) among provenances. Correlation analysis between seed and seedling traits and environmental variables revealed significant positive correlations between seed width and germination percentage, seed width and altitude, seed width and longitude and seed length and latitude. Negative correlations were obtained between seed width and temperature, seed width and rainfall, seed mass and temperature, and germination and temperature of the seed source. As expected, differences in seed trait did not explain the variability in seedling vigour. Determining quantitative variations in seed traits and seedling vigour among provenances and the patterns along environmental gradients are essential for informing decisions on the tree improvement programme of the species.

关键词： Clinal Correlation Environmental gradient Improvement Quantitative

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Germination pretreatment and storage behavior of Terminalia laxiflora seed

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Journal of Forestry Research 2019年第4期30卷 1337-1342页

作者： Befkadu Mewded Debissa Lemessa Hailu Negussie Abiyot Berhanu Forest and Rangeland Biodiversity Directorate Ethiopian Biodiversity Institute

Terminalia laxiflora Engl.&*** an important indigenous and multi-purpose species in *** threatened due to low germination and its storage behavior is *** this study,we aimed to(1)test pretreatments for breaking the dormancy of *** seed and(2)determine its storage *** were subjected to four pretreatments such as soaking,scarification,high-temperature,and *** were done before storage and after 2 years of dry storage at cold temperature(-10℃)based on randomized design with four *** first round of experimental results showed that *** seeds with high temperature treatments at 78℃for 10 min showed significantly higher germination percentage(80%).In the second round experiment,high-temperature treatment at 78℃for15 min,cold water soaking,high-temperature treatment at78℃for 10 min,hot water soaking,and high-temperature treatment at 78℃for 5 min showed significantly higher germination percentage from the remaining treatments(75,64,58,56,and 53%,respectively).To break the dormancy of *** seed and attain good germination result,seeds should be pretreated with high-temperature at 78℃for 10 min to test the initial germination before storage and should be pretreated with high-temperature(at 78℃for15,10,or 5 min),soaked in cold,or hot water for 24 h to monitor the germination after *** two experiments show that *** produces orthodox seed.

关键词： Dormancy breaking Dry storage High-temperature Soaking Storage behavior

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Differential Responses of Electrolyte Leakage and Pigment Compositions in Maize and Sorghum After Exposure to and Recovery from Pre- and Post-Flowering Dehydration

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Agricultural Sciences in China 2010年第6期9卷 813-824页

作者： Abuhay Takele ethiopian Institute of Agricultural Research Melkassa Agricultural Research Center

Drought stress is often the most limiting factor to maize and sorghum production in the semi-arid *** study evaluates the response of electrolyte leakage,chlorophyll,carotenoid and anthocyanin contents in maize （***-2 and sorghum ***） after exposure to and recovery from pre- and post-flowering dehydration in plants grown in a controlled environment growth chamber under constant environmental conditions （12/12 h day/night,28-32/17°C day/night temperature,60-80% RH and PPFD of 1 200-1 400 μmol m-2 s-1）,at the Department of Botany,University of Cape Town,South *** was revealed that dehydration induced increases in electrolyte leakage was observed in both species during both pre- and post-flowering *** leakage was however,higher during post- than pre-flowering dehydration in both *** during both pre- and post-flowering stages caused a decrease in chlorophyll and carotenoid contents in both maize and *** and carotenoid contents of both pre- and post-flowering dehydrated sorghum was markedly higher than that of maize throughout the duration of the dehydration *** opposed to chlorophyll and carotenoid contents,anthocyanin contents increased during pre- and post-flowering dehydration in both *** were however,observed between both species in the response of anthocyanin content to pre- and post-flowering *** recovery of chlorophyll,carotenoid and anthocyanin contents were observed in those plants rehydrated during pre-flowering *** was however,no recovery in both species during post-flowering *** study should help understand some adaptive mechanisms developed by maize and sorghum during the dehydration and rehydration periods and contribute to identify useful traits for breeding programs.

关键词： anthocyanin carotenoid chlorophyll dehydration rehydration

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Choices of Varieties and Demand for Improved Rice Seed in Fogera District of Ethiopia

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Rice science 2018年第6期25卷 350-356页

作者： A.H.MESFIN L.ZEMEDU Agricultural Economics Research Ethiopian Institute of Agricultural Research/Agricultural Research Center Agricultural Economics Research Ethiopian Institute of Agricultural Research/Debrezeit Agricultural Research Center

In this study, 151 households were randomly drawn from three randomly selected Kebele in probability proportional to size method. The demographic and socio-economic factors that determine the participation in improved varieties were household labor availability, education level of the household head,land holdings, distance to the nearest village market, proximity to the main market, and distance to access agricultural extension and access to the source of rice seeds. However, determinants of choice decision varied from cultivar to cultivar. The evidence of the study from the interdependence among the decision of adoption of improved rice varieties suggested that technology adoption will be accelerated by launching a progressively developing package and scheme of rice technology generation, and points to the importance of mobilising additional resources to augment households' efforts at popularization and promotion of improved rice *** findings from Linearized Almost Ideal Demand Systems(LA/AIDS) model showed that compelling evidence for small proportion changes in own prices and cross price of improved rice varieties led to greater than unitary proportionate changes in their purchases. The results generally showed that farmers were very sensitive to changes in improved rice seed prices and incomes. The major implication of the findings was that any intervention to improve farmers' seed purchases should take into account efforts to increase farmers' purchasing power of agricultural inputs like improved seeds and fertilizers.

关键词： improved rice choice seed demand multivariate probit Linearized Almost Ideal Demand Systems

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National Network Operation Center for ethiopian Telecommunications Corporation

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ZTE Communications 2008年第2期6卷 48-50页

作者： Tewodros Hailemeskel ethiopian Telecommunications Corporation Addis Ababa 28233 Ethiopia

ethiopian Telecommunications Corporation (ETC) has acquired a patchwork of systems and processes that makes it difficult to cost-efficiently troubleshoot network faults, launch new services quickly, and track and tune the performance of services once delivered. This patchwork also results in increased operational and capital expenditures, so there is an obvious need for ETC to improve and evolve the network and service management environment. Evolving ETC’s network and service management systems and processes shall be done in a well organized phased approach. ZTE is the first choice for ETC to assume this challenging responsibility and provide the National Network Operation Center (NNOC) solution.

关键词： ETC OSS ZTE NGN

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Reduced efficacy of single-dose albendazole against Ascaris lumbricoides, and Trichuris trichiura, and high reinfection rate after cure among school children in southern Ethiopia: a prospective cohort study

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Infectious Diseases of Poverty 2024年第1期13卷 95-96页

作者： Tigist Dires Gebreyesus Eyasu Makonnen Tafesse Tadele Kalkidan Mekete Habtamu Gashaw Heran Gerba Eleni Aklillu Department of Global Public Health Karolinska Institutet Karolinska University Hospital Stockholm Sweden ethiopian Food and Drug authority Addis Ababa Ethiopia Center for Innovative Drug Development and Therapeutic Trials for Africa College of Health Sciences Addis Ababa University Addis Ababa Ethiopia Departments of Pharmacology and Clinical Pharmacy College of Health Sciences Addis Ababa University Addis Ababa Ethiopia College of Medicine and Health Sciences Hawassa University Hawassa Ethiopia ethiopian Public Health Institute Addis Ababa Ethiopia

Background Mass drug administration(MDA)program of albendazole to at-risk populations as preventive chemo-therapy is the core public health intervention to control soil-transmitted helminths(STHs).Achieving this goal relies on drug effectiveness in reducing the parasite reservoirs in the community and preventing *** assessed the effcacy of albendazole against STH parasite infection and reinfection status after *** A total of 984 schoolchildren infected with at least one type of STH parasite(hookworm,Ascaris lumbri-coides,Trichuris trichiura)in southern Ethiopia were enrolled and received albendazole and praziquantel in MDA campaign conducted from January to March *** exams at week-4 and at week-8 of post-MDA were done using Kato Katz *** primary outcome was effcacy assessed by cure rate(CR)and fecal egg reduction rates(ERRs)at four weeks of *** secondary outcome was reinfection status defined as parasite egg positivity at eight weeks among those who were cured at 4 weeks of *** comparisons in CR and related factors were assessed with chi-square or Fisher's exact *** of CR were examined through univariate and multi-variate regression *** The overall CR and ERR for hookworm infection were 97.2%(95%CI:94.6-99.4)and 97.02%,*** overall CR and ERR for *** were 71.5%(95%CI:68.3-74.6)and 84.5% *** overall CR and ERR and for *** were 49.5%(95%CI:44.8-54.2)and 68.3%,*** CR among moderate *** infec-tion intensity was 28.6%.Among children cured of hookworm,*** and *** at week 4 post-MDA,4.6%,18.3% and 52.4% became reinfected at week-8 post-MDA,*** lower CR(36.6%)and higher reinfection after cure(60.6%)among *** and *** coinfected children than *** only(CR=69.6%,reinfection rate=15.1%)or *** only infected children(CR=55.6%,reinfection rate=47.1%)was obse

关键词： Soil transmitted helminths Neglected tropical diseases Preventive chemotherapy Albendazole School age children Ethiopia

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Modeling the System for Hybrid Renewable Energy Using Highly Efficient Converters and Generator

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CES Transactions on Electrical Machines and Systems 2024年第3期8卷 356-366页

作者： Tefera Kitaba Department of Electrical Power Engineering Ethiopian Defence University College of EngineeringBishoftuDebre Zeit 1041Ethiopia

High-efficient isolated DC/DC converters with a high-efficiency synchronous reluctance generator(SRG)are the ultimate solutions in DC microgrid *** design and modeling of isolated DC/DC converters with the performance of SRG are carried *** the generator side,reactive and active powers are used as pulse width modulation(PWM)control ***,the flux estimator is ***-phase PWM rectifier is used by applying space vector modulation(SVM)with a constant switching frequency for direct power ***,the paper also includes the experimental validation of the *** paper also proposes that highly efficient power converters and synchronous reluctance generators are required to achieve high performance for hybrid renewable energy systems applications.

关键词： DC-DC Duty ratio Isolated DTC SRG Converters

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