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Modeling Global and Local Aspects of Spatial Structure Explicitly in Land-Use Optimization: The Case of Mek'ele City, Ethiopia

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Chinese Journal of Urban and Environmental Studies 2023年第2期11卷 66-96页

作者： ashenafi mehari Paolo Vincenzo GENOVESE School of Architecture Tianjin University International Center of History Critics of Architecture and Restoration of Historical Heritage (ICHCR) College of Civil Engineering and Architecture Zhejiang University

Urban spatial structure remains the center of quest and modeling. The decentralization concept is among the leading literature discourses that guide spatial analyses. In line with the decentralization discourse, the application of land-use optimization as a modeling method has grown significantly. Despite decentralization dominating the contemporary spatial analysis literature, no study so far explicitly declares an end to the centers(and subcenters). While centers(and subcenters) are alive, the land-use optimization has never taken this macro-morphological structure into consideration. This case study frames land-use optimization within the agglomeration and decentralization concepts based on the view that no single conceptual framework addresses spatial analysis sufficiently. On a theoretical level, the link is between coarse morphological assumption(basis of economic geography) and decentralization(basis of sustainable built environment). The paper blends these dual theories, one governing urban macro-morphological structures and the other governing decentralization literature. On a methodological modeling level, it blends centers and other discretized uses. Optimizing four objectives across the complete centralization through multiple centers of gravity to complete the decentralization of urban spatial structures applying Non-dominated Sorting Genetic Algorithm II, the case study findings justify the importance of explicit modeling of the macro-morphological element. It has been observed that multicenter urban forms perform well above both the single center and the dispersed scenarios. It is, therefore,argued that an appropriate approach to land-use optimization is modeling both the macro-spatial element and fine spatial elements. The result further indicates that local land-use planning regulations place the structure of city in a suboptimal state.

关键词： Land-use optimization urban form multicenter city decentralization coarse spatial scale fine spatial scale

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Beyond just a tight fortress:contribution of stroma to epithelial-mesenchymal transition in pancreatic cancer

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Signal Transduction and Targeted Therapy 2020年第1期5卷 328-339页

作者： ashenafi Bulle Kian-Huat Lim Division of Oncology Department of Internal MedicineBarnes-Jewish Hospital and The Alvin J.Siteman Comprehensive Cancer CenterWashington University School of MedicineSt.LouisMO 63110USA

Novel effective treatment is direly needed for patients with pancreatic ductal adenocarcinoma(PDAC).Therapeutics that target the driver mutations,especially the KRAS oncoprotein and its effector cascades,have been ineffective.It is increasing clear that the extensive fibro-inflammatory stroma(or desmoplasia)of PDAC plays an active role in the progression and therapeutic resistance of PDAC.The desmoplastic stroma is composed of dense extracellular matrix(ECM)deposited mainly by the cancer-associatedfibroblasts(CAFs)and infiltrated with various types of immune cells.The dense ECM functions as a physical barrier that limits tumor vasculatures and distribution of therapeutics to PDAC cells.In addition,mounting evidence have demonstrated that both CAFs and ECM promote PDAC cells aggressiveness through multiple mechanisms,particularly engagement of the epithelial-mesenchymal transition(EMT)program.Acquisition of a mesenchymal-like phenotype renders PDAC cells more invasive and resistant to therapyinduced apoptosis.Here,we critically review seminal and recent articles on the signaling mechanisms by which each stromal element promotes EMT in PDAC.We discussed the experimental models that are currently employed and best suited to study EMT in PDAC,which are instrumental in increasing the chance of successful clinical translation.

关键词： stroma transition render

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The invasion of Prosopis juliflora and Afar pastoral livelihoods in the Middle Awash area of Ethiopia

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Ecological Processes 2015年第1期4卷 145-153页

作者： Zeraye H.mehari Natural Resources Research Division Werer Agricultural Research CenterEthiopian Institute of Agricultural Research(EIAR)Addis Ababa 2003Ethiopia

Introduction:An evergreen shrub,Prosopis juliflora is one of the most invasive species in arid and semi-arid areas.Since its introduction to the Middle Awash area of Ethiopia,it has invaded a huge acreage of grass-and rangelands which are life-supporting unit for Afar pastoralists.Methods:Survey,using group discussion and questionnaire,was made to study the effect of P.juliflora invasion on Afar pastoral livelihoods.The obtained data were analyzed using Wilcoxon signed-rank test,chi-square analysis,and logistic regression.Results:According to the result,84%of the total surveyed households rated P.juliflora as undesirable species even though the bush was often used for fuelwood,fencing homesteads,and barn and house construction.Invasion of P.juliflora was also blamed to limit transhumance,occupying settlement areas and affecting multipurpose trees/bushes and grass availability.All these effects put pressure on the livestock assets causing about 80%livestock loss,testing the pastoral livelihoods heavily.Each household,on average,lost 6.5 small stock and 7 cattle during the past 10 years due to health hazards caused by P.juliflora pod.Consequently,P.juliflora as a source of income was considered by a quarter of the surveyed pastoral households,with the age of a household head and change in livestock asset being influential variables in decision-making.Conclusions:In sum,P.juliflora invasion has made livestock rearing extremely difficult which raised pastoralists’ecological vulnerability in the fragile ecosystem they possess.

关键词： Afar pastoralists Middle Awash area Prosopis juliflora Invasion Livestock Livelihoods

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Ecological and floristic study of Hirmi woodland vegetation in Tigray Region,Northern Ethiopia

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Ecological Processes 2020年第1期9卷 615-633页

作者： mehari Girmay Tamrat Bekele Sebsebe Demissew Ermias Lulekal Ministry of Mining and Petroleum of Ethiopia P.O.Box 486Addis AbabaEthiopia Department of Plant Biology and Biodiversity Management Addis Ababa UniversityP.O.Box 3434Addis AbabaEthiopia

The dryland area in Ethiopia covers a substantial region endowed with diverse plant resources.However,the landmass has received less attention even if it has high ecological,environmental,and economic uses.The present study was conducted in Hirmi woodland vegetation,which is one of the dryland areas in Ethiopia,with the objective of investigating the floristic composition,plant community types,vegetation structure,communityenvironment relations and its regeneration status.Vegetation and environmental data were collected from 80 sampling plots with a size of 25 m×25 m designated as the main plots.Diameter at breast height(DBH),height,basal area,density,vertical structure,importance value index(IVI),and frequency were computed.Species diversity and evenness were analyzed using Shannon diversity and evenness indices.The plant community types and vegetation-environment relationships were analyzed using classification and ordination tools,respectively.A total of 171 vascular plant species belonging to 135 genera and 56 families were recorded.About 5.3%of the species were endemic and near-endemic to Ethiopia.The highest number of species was recorded in families Fabaceae(16.4%)and Poaceae(11.7%)followed by Asteraceae(7.0%),Combretaceae,Lamiaceae,and Moraceae(3.5%each).Five plant communities were identified.According to the results from ordination analysis,the floristic composition of these plant communities was significantly affected by altitude,slope,sand,silt,soil organic matter,total nitrogen,and disturbance.The vegetation structure reveals that a large number of individual species was categorized in the lower DBH,frequency,and height classes.The highest Shannon diversity index and evenness values of the study area were 4.21 and 0.95,respectively.Anogeissus leiocarpa,Combretum hartmannianum,Ziziphus mucronata,Terminalia macroptera,and Acacia polyacantha were the species with high IVI.Some endemic plants were in the IUCN red list categories of Ethiopia and Eritrea.The overall regeneration status of the study area was

关键词： Diversity Dryland Hirmi woodland Regeneration status Plant communities

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埃塞俄比亚南方各族州德拉什特区公立中学校本督导的影响因素研究

埃塞俄比亚南方各族州德拉什特区公立中学校本督导的影响因素研究

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作者： ashenafi Taye Mengesha 华东师范大学

学位级别：硕士

本研究旨在探查影响南方各族州德拉什特区(DSW)政府中学校本督导的因素。具体而言,本研究评估了校本督导员在中学推行校本督导活动时所面临的挑战。本研究采用并行混合研究设计,通过问卷调查、访谈和文献研究收集量化和质性数据。171名... 详细信息

本研究旨在探查影响南方各族州德拉什特区(DSW)政府中学校本督导的因素。具体而言,本研究评估了校本督导员在中学推行校本督导活动时所面临的挑战。本研究采用并行混合研究设计,通过问卷调查、访谈和文献研究收集量化和质性数据。171名相关人员通过可用性和比例性以及简单随机抽样,被纳入本研究。其中,问卷调查共计回收有效问卷163份,回答者包括123名教师、40名校本督导员、3名区级学校督导员和5名区级教育干事,参加访谈的受访者包括3名学校督导员和5名区级教育官员。对通过问卷收集的数据,本研究一方面使用百分比、平均值和标准差等描述性统计,另一方面将回答者分为教师和校本督导员,在对比两组人员的平均值之外,进行独立样本t检验,比较两组的异同。调查结果显示,校本督导的各种方式未能很好地指出教师教学的局限性,也没有为教师纠正课堂教学实践提供足够的支持。此外,校本督导员没有与学校和社区合作,解决教学过程中的资金和材料问题。校本监督受到许多问题的影响,例如校本督导员能力不足,督导员知识和技能培训项目缺乏,校本督导手册缺失,开展督导活动的预算拨款不足,学校督导工作量繁重等。研究得出以下结论:德拉什特区的中学未能有效开展校本监督活动,校本督导未能指出教师的局限性。研究建议,学校校长应作出巨大努力,通过定期培训来提高督导员的能力。研究还建议区级学校督导员与区教育办公室合作,为教师提供关于学校督导的培训。这可以为教师、相关方和督导员之间分享经验提供良好的机会,从而推动有效的学校督导。

关键词：监督校本督导德拉什特区中学南方各族州

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Genome wide identification and characterization of MAPK genes reveals their potential in enhancing drought and salt stress tolerance in Gossypium hirsutum

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Journal of Cotton Research 2022年第3期5卷 261-273页

作者： SADAU Salisu Bello mehari Teame Gereziher AHMAD Adeel TAJO Sani Muhammad IBRAHIM Sani IQBAL Muhammad Shahid ELASAD Mohammed ZHANG Jingjing WEI Hengling YU Shuxun State Key Laboratory of Cotton Biology Institute of Cotton ResearchChinese Academy of Agricultural SciencesAnyangHenan 455000China Key Laboratory of Biology and Genetic Improvement of Oil Crops Ministry of AgricultureOil Crops Research InstituteChinese Academy of Agricultural SciencesWuhan 430062China Department of Science and Technology Education Bayero University KanoP.O.Box 3011KanoNigeria Agricultural Research Corporation(ARC) P.O.Box 126Wad MedaniSudan.

Background:The cotton crop is universally considered as protein and edible oil source besides the major contributor of natural fiber and is grown in tropical and subtropical regions around the world Unpredicted environmental stresses are becoming significant threats to sustainable cotton production,ultimately leading to a substantial irreversible economic loss.Mitogen-activated protein kinase(MAPK)is generally considered essential for recognizing environmental stresses through phosphorylating downstream signal pathways and plays a vital role in numerous biological processes.Results:We have identified 74 MAPK genes across cotton,41 from G.hirsutum,19 from G.raimondii,whereas 14 have been identified from G.arboreum.The MAPK gene-proteins have been further studied to determine their physicochemical characteristics and other essential features.In this perspective,characterization,phylogenetic relationship,chromosomal mapping,gene motif,cis-regulatory element,and subcellular localization were carried out.Based on phylogenetic analysis,the MAPK family in cotton is usually categorized as A,B,C,D,and E clade.According to the results of the phylogenic relationship,cotton has more MAPKS genes in Clade A than Clade B.The cis-elements identified were classified into five groups(hormone responsiveness,light responsiveness,stress responsiveness,cellular development,and binding site).The prevalence of such elements across the promoter region of these genes signifies their role in the growth and development of plants.Seven GHMAPK genes(GH_A07G1527,GH_D02G1138,GH_D03G0121,GH_D03G1517,GH_D05G1003,GH_D11G0040,and GH_D12G2528)were selected,and specific tissue expression and profiling were performed across drought and salt stresses.Results expressed that six genes were upregulated under drought treatment except for GH_D11G0040 which is downregulated.Whereas all the seven genes have been upregulated at various hours of salt stress treatment.Conclusions:RNA sequence and qPCR results showed that genes as differentially expressed across

关键词： Cotton MAPK gene Drought stress Salt stress

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Improving milk safety at farm-level in an intensive dairy production system:relevance to smallholder dairy producers

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Food Quality and Safety 2018年第3期2卷 135-143页

作者： Habtamu Lemma D. ashenafi Mengistu Taddese Kuma Berhanu Kuma Wolaita Sodo University College of AgriculturePOB 138Ethiopia Addis Ababa University College of Veterinary Medicine and AgricultureEthiopia Ethiopian Development Research Institute Ethiopia

Objective:This paper discusses methods for improving milk safety in smallholder dairying.Methodology:Analyzing best practices/experiences of selected countries and Ethiopian dairy farming as a case study(household survey and milk testing).Results:The coliform count was slightly higher than European standard.The value of total bacterial count found was higher than the standard of bacteriological quality of milk.Somatic Cell count is slightly higher than US standard,but it is in the range of the EU standard.Moreover,there were other associated challenges facing dairy farmers,including shortage of feed concentrate and water,milk marketing,health of dairy stock,and manure management.Some better practices were also observed including literacy and dairying experience of smallholder dairy producing-households.Despite this,increased availability of some dairy stakeholders and their efforts would also be an added advantage.The efforts of private veterinarians to engage in provision of drugs and on-call home-treatment for stall-fed cows were good,but this needs to be complemented with laboratory based-diagnostic/clinical and advisory services prevent diseases.Conclusion:Improvement of milk safety can be achieved through good management practices by dairy farmers,market incentives,and increased efforts of various stakeholders and the adoption of best practices.In this regard,a coordinated action involving all stakeholders is needed to implement preventative/control measures,quality management strategies,and appropriate regulation while supporting and building capacity of smallholder dairy producers to minimize risks associated with milk production.

关键词： milk safety challenges prevention intensive dairy systems smallholders dairy farms.

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Titanium effect on the microstructure and properties of laminated high boron steel plates

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International Journal of Minerals,Metallurgy and Materials 2015年第5期22卷 492-499页

作者： Lin-lin Yuan Jing-tao Han Jing Liu Dong-bin Wei mehari Zelalem Abathun School of Materials Science and Engineering University of Science and Technology Beijing School of Electrical Mechanical and Mechatronic Systems University of TechnologySydney

High-boron steel is an important material used for thermal neutron shielding. The appropriate amount of added boron must be de- termined because excessive boron may deteriorate the steel＇s workability. A uniform microstructure can be formed by adding titanium to boron steel. In this study, casting and hot rolling were used to fabricate laminated high-boron steel plates whose cores contained 2.25wt% boron and 0wt%-7.9wt% titanium. The effects of titanium content and hot-rolling and heat-treatment processes on the microstructure and properties of the laminated plates were studied. The results indicated that the optimum titanium content was 5.7wt% when the boron content was 2.25wt%, and that the best overall properties were obtained after heat treatment at 1100℃ for 4 h. The tensile strength, yield strength, and elongation at the specified temperature and holding time were as high as 526.88 MPa, 219.36 MPa, and 29%, respectively.

关键词： boron steel laminated materials titanium boride hot rolling heat treatment

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The Need for Agricultural Water Management in Sub-Saharan Africa

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Journal of Water Resource and Protection 2016年第9期8卷 835-843页

作者： Kbrom Ambachew Gebrehiwot mehari Gidey Gebrewahid Department of Water Resources and Irrigation Engineering Institute of Technology Haramaya University Haramaya Ethiopia

This paper discusses the current and future conditions that affect water resources and the constraints of water (agricultural) management in sub-Saharan Africa and suggests remedial measures to be considered by policy makers. The pressure on the quantity and quality of water resources is rising in sub-Saharan Africa due to the increased demand of water for agriculture and other purposes as a result of increase in population and food demand. The availability of water is also under threat from changing climate and as a result, water scarcity is expected in many countries in sub-Saharan Africa. On the other hand, the availability of water for agriculture is expected to further shrink due to the increasing demand of water for other purposes like industry, manufacturing and environmental requirement. The current poor efficiency rate of irrigation systems and massive expansion of irrigated area is expected to further exacerbate the water scarcity. Hence, a water management policy focused on maximization of water use efficiency and water productivity should be prioritized in order to meet the food demand of the growing population and cope with water scarcity problems. Engineering and management intervention integrated with strong society awareness and participation is considered very crucial in enhancing water use efficiency and crop water productivity.

关键词： Water Scarcity Water Management Water Use Efficiency Water Productivity Sub-Saharan Africa

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Investigation of Laser Induced Breakdown Spectroscopy(LIBS)for the Differentiation of Nerve and Gland Tissue-A Possible Application for a Laser Surgery Feedback Control Mechanism

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Plasma Science and Technology 2016年第6期18卷 654-660页

作者： F.mehari M.ROHDE C.KNIPFER R.KANAWADE F.KLAMPFL W.ADLER N.OETTER F.STELZLE M.SCHMIDT Clinical Photonics Lab Erlangen Graduate School in Advanced Optical Technologies(SAOT)Friedrich-Alexander-Universitat Erlangen-NurnbergPaul-Gordan-Str.691052 ErlangenGermany Institute of Photonic Technologies Friedrich-Alexander-Universitat Erlangen-NiirnbergKonrad-Zuse-Str.3/591052 ErlangenGermany Department of Oral and Maxillofacial Surgery University Hospital ErlangenFriedrich-Alexander-Universitat Erlangen-NurnbergGliickstrasse 1191054 ErlangenGermany Chair of Biometry and Epidemiology Friedrich-Alexander-Universitat Erlangen-Niirnberg Waldstrabe 691054 ErlangenGermany

Laser surgery provides clean,fast and accurate modeling of tissue.However,the inability to determine what kind of tissue is being ablated at the bottom of the cut may lead to the iatrogenic damage of structures that were meant to be preserved.In this context,nerve preservation is one of the key challenges in any surgical procedure.One example is the treatment of parotid gland pathologies,where the facial nerve（N.VII） and its main branches run through and fan out inside the glands parenchyma.A feedback system that automatically stops the ablation to prevent nerve-tissue damage could greatly increase the applicability and safety of surgical laser systems.In the present study,Laser Induced Breakdown Spectroscopy（LIBS） is used to differentiate between nerve and gland tissue of an ex-vivo pig animal model.The LIBS results obtained in this preliminary experiment suggest that the measured spectra,containing atomic and molecular emissions,can be used to differentiate between the two tissue types.The measurements and differentiation were performed in open air and under normal stray light conditions.

关键词： laser induced breakdown spectroscopy plasma chemical composition nerveparotid gland

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