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EXPLORING THE RECYCLING OF MANURE FROM URBAN LIVESTOCK FARMS:A CASE STUDY IN ETHIOPIA

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Frontiers of Agricultural Science and Engineering 2021年第1期8卷 159-174页

作者： Solomon Tulu TADESSE Oene OENEMA christy van BEEK Fikre Lemessa OCHO Department of Horticulture and Plant Sciences College of Agriculture and Veterinary MedicineJimma UniversityJimmaEthiopia Department of Soil Quality Wageningen University and Research6700 AA Wageningenthe Netherlands Wageningen Environmental Research 6700 AA Wageningenthe Netherlands SoilCares Foundation Nieuwe Kanaal 7c6709 PA Wageningenthe Netherlands

Urban population growth is driving the expansion of urban and peri-urban agriculture(UPA)in developing *** is providing nutritious food to residents but the manures produced by UPA livestock farms and other wastes are not properly *** paper explores the effects of four scenarios:(1)a reference scenario(business as usual),(2)increased urbanization,(3)UPA intensification,and(4)improved technology,on food-protein self-sufficiency,manure nitrogen(N)recycling and balances for four different zones in a small city(jimma)in Ethiopia during the period *** N mass flow model with data from farm surveys,field experiments and literature was used.A field experiment was conducted and N use efficiency and N fertilizer replacement values differed among the five types of composts derived from urban livestock manures and kitchen *** N use efficiency and N fertilizer replacement values were used in the N mass flow *** manures were the main organic wastes in urban areas,although only 20 to 40%of animal-sourced food consumed was produced in UPA,and only 14 to 19%of protein intake by residents was *** indicate that manure production in UPA will increase 3 to 10 times between 2015 and 2050,depending on urbanization and UPA *** 13 to 38%of manure N will be recycled in ***-gate N balances of UPA livestock farms will increase to>1 t·ha−1 in *** livestock productivity and feed protein conversion to animal-sourced food will roughly halve manure N *** of waste recycling were high and indicate the need for government *** of these senarios are wake-up calls for all stakeholders and indicate alternative pathways.

关键词： compost food self-sufficiency livestock production nitrogen balance nitrogen use efficiency scenario analysis

Changes in interstitial fluid flow,mass transport and the bone cell response in microgravity and normogravity

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Bone Research 2022年第4期10卷 696-714页

作者： Fei Wei Kendal Flowerdew Michael Kinzel Luigi EPerotti jackson Asiatico Mahmoud Omer Candice Hovell Veerle Reumers Melanie j.Coathup Biionix Cluster Department of Internal MedicineCollege of MedicineUniversity of Central FloridaOrlandoFLUSA Marian University College of Osteopathic Medicine IndianapolisINUSA Department of Mechanical and Aerospace Engineering University of Central FloridaOrlandoFLUSA Imec USA 194 NeoCity WyOrlandoFLUSA

In recent years,our scientific interest in spaceflight has grown exponentially and resulted in a thriving area of research,with hundreds of astronauts spending months of their time in space.A recent shift toward pursuing territories farther afield,aiming at near-Earth asteroids,the Moon,and Mars combined with the anticipated availability of commercial flights to space in the near future,warrants continued understanding of the human physiological processes and response mechanisms when in this extreme *** skeletal loss,more severe than any bone loss seen on Earth,has significant implications for deep space exploration,and it remains elusive as to why there is such a magnitude of difference between bone loss on Earth and loss in *** removal of gravity eliminates a critical primary mechano-stimulus,and when combined with exposure to both galactic and solar cosmic radiation,healthy human tissue function can be negatively *** additional effect found in microgravity,and one with limited insight,involves changes in dynamic fluid *** provide the most fundamental way to transport chemical and biochemical elements within our bodies and apply an essential mechano-stimulus to ***,the cell cytoplasm is not a simple liquid,and fluid transport phenomena together with viscoelastic deformation of the cytoskeleton play key roles in cell *** microgravity,flow behavior changes drastically,and the impact on cells within the porous system of bone and the influence of an expanding level of adiposity are not well *** review explores the role of interstitial fluid motion and solute transport in porous bone under two different conditions:normogravity and microgravity.

关键词： flow flow apply

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超硬微结构表面模具的精密磨削加工技术

机械工程学报 2011年第23期47卷 174-179页

作者：郭兵赵清亮 jackson Mark j 赵玲玲哈尔滨工业大学机电学院哈尔滨150001 普渡大学技术学院

针对超硬模具材料,研究磨削方式(顺磨和逆磨)、进给率和主轴转速等磨削参数对磨削后微结构表面的表面粗糙度和尖锐部分完整性的影响规律。基于磨削结果,对微结构表面质量不均一现象以及微结构表面磨削过程中的砂轮磨损分布进行研究。试... 详细信息

针对超硬模具材料,研究磨削方式(顺磨和逆磨)、进给率和主轴转速等磨削参数对磨削后微结构表面的表面粗糙度和尖锐部分完整性的影响规律。基于磨削结果,对微结构表面质量不均一现象以及微结构表面磨削过程中的砂轮磨损分布进行研究。试验结果表明磨削后的微结构侧表面粗糙度小于底面粗糙度。采用逆磨可以获得更低的粗糙度和更加完整、锋利的尖锐部分。磨削后的表面粗糙度随着进给率的降低而减小,当进给率为0.2 ***–1时,微结构底面平均表面粗糙度Ra89 nm,侧面为Ra 60 nm。磨削后,尖锐部分圆弧半径随进给率的降低呈现减小趋势,当进给率为0.5 ***–1时,其平均圆弧半径最小,为0.67μm。主轴转速对表面粗糙度和尖锐部分圆弧半径的影响不大。由阶梯光栅表面结构性引起的,相对于其各个表面的磨削轨迹不相同,是导致磨削后阶梯光栅表面质量不均一现象主要原因。在微结构表面的磨削加工过程中,相对于砂轮的径向和轴向磨损,砂轮的形貌磨损更为严重。

关键词：磨削超硬材料微结构表面尖锐部分质量不均一性砂轮磨损

Comparison between vitrified bond and resin bond diamond grinding wheel in grinding PDC

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金刚石与磨料磨具工程 2008年第5期28卷 12-15页

作者： Zhang Xiaofu Zhang Hongxia Lu Anxian Mark j. jackson School of Materials Science and Engineering Central South University Changsha 410083 China School of Chemistry and Chemical Technology Henan University of Technology Zhengzhou 450052 China Centre for Advanced Manufacturing MET Purdue University West Lafayette Indiana 47907 USA

In this research,the advantages and disadvantages of the cylindrical grinding process of Polycrystalline Diamond Compacts(short for PDC) with vitrified and resin bond diamond grinding wheel are *** research results show that the vitrified bond diamond grinding wheels,which use Ti-coated diamond grains as abrasive and glass ceramic as bond,have many advantages in grinding *** with resin diamond grinding wheel,vitrified bond wheels lead to 35% grinding cost reduced,40% grinding time of each PDC saved,and the size precision of PDC improved(from ±0.03mm to ±0.01mm).When grinding feed is <0.10 mm,the grinding ratio increases with increased grinding ***,when the grinding feed exceeds 0.10 mm,the grinding radio decreases rapidly with the increasing of grinding *** disadvantage of this kind of grinding wheel is that the brightness of the ground PDC cylinder is not as shining as that processed by resin bond diamond grinding wheel.

关键词：树脂金刚石砂轮磨削工艺

Future sea level rise along the coast of China and adjacent region under 1.5℃ and 2.0℃ global warming

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Advances in Climate Change Research 2020年第3期11卷 227-238页

作者： QU Ying LIU Yonggang Svetlana jEVREjEVA Luke P.jackson Department of Atmospheric and Oceanic Sciences School of PhysicsPeking UniversityBeijing100871China National Oceanography Center LiverpoolL35DAUK Programme for Economic Modelling Nuffield CollegeOxford UniversityOX1 INFUK

Although future sea level rise along the China coast has been projected by various studies for different representative concentration pathways(RCPs),the projections for different warming thresholds,e.g.1.5℃ and 2.0℃,have not been done specifically for this region,to the best of our *** provide such a projection here based on the climate projections of Coupled Model Intercomparison Project Phase 5(CMIP5).The projections are given for 20 tide-gauge stations along the coast of China,Korea,japan,and *** land motion(VLM)is also estimated for stations that have tide gauge records and satellite altimetry both covering the period of *** land motion(LLM)is then estimated by subtracting the land motion due to glacial isostatic adjustment(GIA)from *** considering LLM,sea level rise by 2100 at median probability is projected to be 38-49 cm relative to the average sea level over 1986-2005 under warming of 1.5℃,and increase to 46-57 cm when the warming threshold is increased to 2.0℃.The steric component is the main contributor to this increase in sea *** of LLM will not affect the sea level increase between the two warming thresholds,but it will make the local sea level rise by 2100 at certain locations substantially higher(up to 36 cm)or lower(up to 13 cm).

关键词： Sea level rise Coast of China Tide gauge records Vertical land motion Warming of 1.5℃ Warming of 2.0℃

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竖直管道内湍流混合对流换热研究

工程热物理学报 2005年第2期26卷 286-288页

作者：刘峰姜培学 S HE j D jackson 清华大学热能工程系热能动力工程与热科学重点实验室北京100084 英国罗伯特戈登大学工学院英国曼彻斯特大学工学院

本文对空气在竖直圆管中的湍流混合对流换热进行了实验研究和数值模拟,并对异种气体(氦气)对混合对流换热的影响进行了初步的实验研究。研究发现,空气在竖直圆管中向上流动时,随着热流密度的不断增大,出现换热恶化现象。如果浮升力足够... 详细信息

本文对空气在竖直圆管中的湍流混合对流换热进行了实验研究和数值模拟,并对异种气体(氦气)对混合对流换热的影响进行了初步的实验研究。研究发现,空气在竖直圆管中向上流动时,随着热流密度的不断增大,出现换热恶化现象。如果浮升力足够大,则换热效果在降到最低点后又好转。在实验过程中,由于实验条件所限没有发现异种气体对混合对流换热有显著的影响。

关键词：混合对流换热恶化实验研究数值模拟

Calcium-mediated paired pulse depression in juvenile rat dorsal striatum

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Neural Regeneration Research 2012年第10期7卷 772-777页

作者： Yufeng Xie Michael F. jackson john F. MacDonald Robarts Research Institute University of Western Ontario London Ontario Canada Department of Physiology and Pharmacology University of Western Ontario London Ontario Canada Department of Anatomy and Cell Biology University of Westem Ontario London Ontario Canada

As the major division of the basal ganglia, neostriatum forms mutual connections with multiple brain areas and is critically involved in motor control and learning/memory. Long-term synaptic plasticity has been widely studied in different species recently. However, there are rare reports about the short-term synaptic plasticity in neostratium. In the present study, using field excitatory postsynaptic potentials recording, we reported one form of short-term synaptic plasticity that is paired pulse depression in juvenile rat dorsal striatum slices induced by stimuli of the white matter. The field excitatory postsynaptic potentials could be abolished by α-amino-3-hydroxy-5-methylizoxazole-4-propionic acid receptor antagonist, 6-cyano-7-nitroquinoxaline-2,3-dione, but not by gamma-aminobutyric acid type A receptor antagonist bicuculline or dopamine D1 receptor antagonist SKF-81297. The paired pulse depression in the corticostratial pathway was different from paired pulse facilitation in the hippocampal CA1 synapse. In addition, the paired pulse depression was not affected by bath application of gamma-aminobutyric acid type A receptor antagonist or dopamine D1 receptor antagonist. However, low calcium and high magnesium could attenuate the paired pulse depression. These findings suggest a more complicated plasticity form in the dorsal striatum of juvenile rats that is different from that in the hippocampus, which is related with extracellular calcium.

关键词： paired pulses depression dorsal striatum calcium juvenile rats

FtsH4 protease controls biogenesis of the PSII complex by dual regulation of high light-inducible proteins

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Plant Communications 2023年第1期4卷 272-286页

作者： Vendula Krynická Petra Skotnicová Philip j.jackson Samuel Barnett jianfeng Yu Anna Wysocka Radek Kaña Mark j.Dickman Peter j.Nixon C.Neil Hunter josef Komenda The Czech Academy of Sciences Institute of MicrobiologyCentre AlgatechNovohradská 23737901 TreboñCzech Republic Plants Photosynthesis and SoilSchool of BiosciencesUniversity of SheffieldSheffield S102TNUK Department of Chemical and Biological Engineering University of SheffieldSheffield S13JDUK Sir Ernst Chain Building-Wolfson Laboratories Department of Life SciencesSouth Kensington CampusImperial College LondonLondon SW72AZUK Faculty of Science University of South Bohemia37005 Ceské BudějoviceCzech Republic

FtsH proteases are membrane-embedded proteolytic complexes important for protein quality control and regulation of various physiological processes in bacteria,mitochondria,and *** most cyanobacteria,the model species Synechocystis *** 6803 contains four FtsH homologs,FtsH1–***1–FtsH3 form two hetero-oligomeric complexes,FtsH1/3 and FtsH2/3,which play a pivotal role in acclimation to nutrient deficiency and photosystem Ⅱ quality control,***4 differs from the other three homologs by the formation of a homo-oligomeric complex,and together with Arabidopsis thaliana AtFtsH7/9 orthologs,it has been assigned to another phylogenetic group of unknown *** results exclude the possibility that Synechocystis FtsH4 structurally or functionally substitutes for the missing or non-functional FtsH2 subunit in the FtsH2/3 ***,we demonstrate that FtsH4 is involved in the biogenesis of photosystem Ⅱ by dual regulation of high light-inducible proteins(Hlips).FtsH4 positively regulates expression of Hlips shortly after high light exposure but is also responsible for Hlip removal under conditions when their elevated levels are no longer *** provide experimental support for Hlips as proteolytic substrates of *** labeling of FtsH4 enabled us to assess its localization using advanced microscopic *** show that FtsH4 complexes are concentrated in well-defined membrane regions at the inner and outer periphery of the thylakoid *** on the identification of proteins that co-purified with the tagged FtsH4,we speculate that FtsH4 concentrates in special compartments in which the biogenesis of photosynthetic complexes takes place.

关键词： thylakoid photosystemⅡbiogenesis FtsH4 high light-inducible protein proteolysis

Effect of coordination structure of aluminum on its activation from minerals and Oxisols during their acidification

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Pedosphere 2024年第5期34卷 916-928页

作者： Kewei LI Yangxiaoxiao SHI jackson Nkoh NKOH jun jIANG Renkou XU State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China University of Chinese Academy of Sciences Beijing 100049China

The types and contents of phyllosilicate minerals in soils play an important role in soil acidification,as soil acid buffering capacity varies with the composition of the phyllosilicate *** addition to aluminum-oxygen(Al-O)octahedrons,a certain number of Al-O tetrahedrons exist in phyllosilicate minerals due to the isomorphic substitution of silicon ion(Si4+)by aluminum ion(Al3+)in Si-O tetrahedrons of ***,the effect of the two coordination structures of Al on the release of Al during mineral acidification has not yet been ***,the differences in Al activation in phyllosilicate minerals and soils with different Al coordination structures were investigated through constant-p H experiments and27Al magic-angle spinning nuclear magnetic resonance(MAS-NMR)*** results of27Al MAS-NMR spectra showed that kaolinite contained Al-O octahedrons,phlogopite and illite contained Al-O tetrahedrons,and vermiculite composite contained both octahedral and tetrahedral *** p Hvermiculite composite>phlogopite>kaolinite,which was consistent with the orders of cation exchange capacity and content of tetrahedral Al of the *** to the rate constants,the Al release rates were in the order of phlogopite>illite>vermiculite composite>kaolinite at p H *** for phlogopite,the Al release rates in these minerals increased with decreasing suspension p ***,the Al release contents and rates were greater in phlogopite,illite,and vermiculite composite containing Al-O tetrahedrons than in kaolinite containing only Al-O *** Oxisols derived from basalt with different ages were selected for similar ***27Al MAS-NMR spectra of the Oxisols showed that the 0.01-million-year(Ma)Oxisol contained both octahedral and tetrahedral Al,while the 1.33-Ma Oxisol contained only Al-O *** contents of both exchan

关键词： Al-O octahedrons Al-O tetrahedrons aluminum release exchangeable Al phyllosilicate minerals soil acidification