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Implications of Land Use Land Cover Change and Climate Variability on Future Prospects of Beef Cattle Production in the Lake Victoria Basin

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American Journal of Climate Change 2015年第5期4卷 461-473页

作者： Japhet Joel Kashaigili emmanuel zziwa Siwa Ernest Emma Laswai Bernard Musana Segatagara Denis Mpairwe Reuben Mpuya Joseph Kadigi Cyprian Ebong Samuel Katambi Mugasi Germana Henry Laswai Mutimura Mupenzi Polycarp Jacob Ngowi Ibrahim Lwaho Kadigi Sokoine University of Agriculture Morogoro Tanzania Makerere University Kampala Uganda Association for Strengthening Agricultural Research in Eastern and Central Africa (ASARECA) Entebbe Uganda Tanzania Forestry Research Institute (TAFORI) Morogoro Tanzania Rwanda Agriculture Board (RAB) Kigali Rwanda National Agricultural Advisory Services (NAADS) Kampala Uganda

This paper presents the lessons learnt from a research project titled “Improving Beef Cattle Productivity for Enhanced Food Security and Efficient Utilization of Natural Resources in the Lake Victoria Basin” which includes Tanzania, Uganda and Rwanda. The key focus is on the implications of land use land cover change and climate variability on the future prospects of beef cattle production in this region. The study utilizes information and data from natural resources and climate components to deduce the impact of land use and land cover changes on climate variability. Additional analysis is conducted to summarize the land use and land cover data to carry out analysis on climate data using the Mann-Kendal test, linear regression and moving averages to reveal patterns of change and trends in annual and seasonal rainfall and temperature. The findings reveal that the study areas of Rwanda, Uganda and Tanzania in the Lake Victoria Basin (LVB) have changed over time following land cover manipulations and land use change, coupled with climate variability. The grazing land has been converted to agriculture and settlements, thereby reducing cattle grazing land which is the cheapest and major feed source for ruminant livestock production. Although the cattle population has been on the increase in the same period, it has been largely attributed to the fact that the carrying capacity of available grazing areas had not been attained. The current stocking rates in the LVB reveal that the rangelands are greatly overstocked and overgrazed with land degradation already evidenced in some areas. Climate variability coupled with a decrease in grazing resources is driving unprecedented forage scarcity which is now a major limiting factor to cattle production. Crop cultivation and settlement expansion are major land use types overtaking grazing lands;therefore the incorporation of crop residues into ruminant feeding systems could be a feasible way to curtail rangeland degradation and inc

关键词： Beef Cattle Production Climate Variability Crop Residues Land Use Land Cover Change Lake Victoria Basin

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Modelling die filling with charged particles using DEM/CFD

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Particuology 2012年第2期10卷 229-235页

作者： emmanuel Nkem Nwose School of Chemical Engineering University of Birmingham Birmingham B15 2TT UK

The effects of electrostatic charge on powder flow behaviour during die filling in a vacuum and in air were analysed using a coupled discrete element method and computational fluid dynamics （DEM]CFD） code, in which long range electrostatic interactions were implemented. The present 2D simulations revealed that both electrostatic charge and the presence of air can affect the powder flow hehaviour during die filling. It was found that the electrostatic charge inhibited the flow of powders into the die and induced a loose packing structure. At the same filling speed, increasing the electrostatic charge led to a decrease in the fill ratio which quantifies the volumetric occupancy of powder in the die. In addition, increasing the shoe speed caused a further decrease in the fill ratio, which was characterised using the concept of critical filling speed, When the electrostatic charge was low, the air/particle interaction was strong so that a lower critical filling speed was obtained for die filling in air than in a vacuum. With high electrostatic charge, the electrostatic interactions became dominant. Consequently, similar fill ratio and critical filling speed were obtained for die filling in air and in a vacuum.

关键词： DEMCFDElectrostaticsDie fillingPowder flowCohesionCharged particles

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Scanning electron microscopy of fruits in the West African Polygonaceae

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Journal of Systematics and Evolution 2010年第5期48卷 336-343页

作者： Abiodun emmanuel AYODELE Key Laboratory of Biodiversity and Biogeography Kunming Institute of BotanyChinese Academy of Science

The fruit morphology of 18 taxa representing seven genera of the family Polygonaceae in West Africa was investigated using scanning electron *** achenes are trigonous,lenticular,globose,subglobose,heart shaped,ovoid,or cone *** range from 0.12×0.10 cm2 in Polygonum plebeium to 7.87×0.58 cm2 in Afrobrunnichia *** are brown to *** cells are isodiametric in ***,irregular in ***,Antigonon leptopus,and Harpagocarpus snowdenii,and polygonal in other *** walls are straight,curved,or undulate and are either raised or *** erecta is characterized by deeply sinuate lateral *** cell surface may be smooth or tuberculate or fibrillate in the family,usually covered with wax *** combination of these characters is mainly taxonomically useful at the tribal level and rarely at the specific or infraspecific level for the delimitation of the taxa.

关键词： fruit Polygonaceae SEM taxonomy West Africa.

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Systems Analysis of Vulnerability to Hydrometeorological Threats: An Exploratory Study of Vulnerability Drivers in Northern Zimbabwe

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International Journal of Disaster Risk Science 2019年第2期10卷 204-219页

作者： emmanuel Mavhura Department of Geography Bindura University of Science Education

Disasters result from complex interactions of hazards and vulnerability conditions. Reducing human exposure and sensitivity to threats can reduce disaster impact. Prior knowledge about community vulnerability levels is crucial to minimizing potential losses from future threats. Most vulnerability studies focus on high-impact disasters and their temporal and spatial analyses. Yet highfrequency, low-impact disasters have a cumulative potential to severely disrupt or damage socioeconomic *** is limited knowledge especially in the global south about the creation of vulnerability to hydrometeorological threats. Using a systems approach, this study explores ways in which communities in the northern semiarid tropics of Zimbabwe are vulnerable to hydrometeorological *** predominantly qualitative study used literature review, interviews, transect walks, and focus groups to gather data from selected samples involving smallholder farmers with in-depth knowledge about community vulnerability. The results show that the communities are vulnerable to multiple hydrometeorological threats due to multiple interacting factors including rainfed and floodbased farming, land tenure, topography, climate, and other socioeconomic conditions such as inadequate income sources and high poverty. In order to reduce vulnerability,this study provides five policy options for government and nongovernmental organization interventions, including the need to transform rural economies beyond the traditional rainfed and flood-based farming systems.

关键词： Community vulnerability Flood-based farming Hydrometeorological threats Rainfed agriculture Zimbabwe

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Revaluation of deuterostome phylogeny and evolutionary relationships among chordate subphyla using mitogenome data

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Journal of Genetics and Genomics 2009年第3期36卷 151-160页

作者： emmanuel Mukwaya Key Laboratory of Ministry of Education for Coastal and Wetland Ecosystems School of Life SciencesXiamen University

The traditional knowledge in textbooks indicated that cephalochordates were the closest relatives to vertebrates among all extant organisms. However, this opinion was challenged by several recent phylogenetic studies using hundreds of nuclear genes. The researchers suggested that urochordates, but not cephalochordates, should be the closest living relatives to vertebrates. In the present study, by using data generated from hundreds of mtDNA sequences, we revalue the deuterostome phylogeny in terms of whole mitochondrial genomes （mitogenomes）. Our results firmly demonstrate that each of extant deuterostome phyla and chordate subphyla is monophyletic. But the results present several alternative phylogenetic trees depending on different sequence datasets used in the analysis. Although no clear phylogenetic relationships are obtained, those trees indicate that the ancient common ancestor diversified rapidly soon after their appearance in the early Cambrian and generated all major deuterostome lineages during a short historical period, which is consistent with ＂Cambrian explosion＂ revealed by paleontologists. It was the 520-million-year＇s evolution that obscured the phylogenetic relationships of extant deuterostomes. Thus, we conclude that an integrative analysis approach rather than simply using more DNA sequences should be employed to address the distant evolutionary relationship.

关键词： mitochondrial genome deuterostomes phylogeny gene arrangement chordate evolutionary relationship amphioxus

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Physico-chemical characterization of a farmland affected by wastewater in relation to heavy metals

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第3期9卷 366-372页

作者： emmanuel U. ONWEREMADU Department of Soil Science and Technology Federal University of Technology PMB 1526 Owerri Nigeria

This study investigated selected properties of soils affected by wastewater and its relationship with some heavy metals. A free survey technique involving target sampling was used in siting soil profile pits. Soil samples were collected based on horizon differentiation and analyzed using routine and special analytical techniques. Soil data were subjected to correlation analysis using SAS program. Results show that all heavy metals studied had values above critical limits in the polluted soils using known standards and that these biotoxic metals decreased with soil depths. Highly significant (P=0.01 and 0.05) relationships were established between investigated heavy metals and some soil properties, especially soil pH and organic matter. Further studies involving more edaphic properties, biotoxic metals and their bioaccessibility in crops growing on wastewater soils will surely enhance knowledge and management of these highly anthropogenically influenced soils of the study site.

关键词： Bioavailability Characterization Heavy metals Soil pollution Wastewater

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A Unified Spatio-Temporal Framework of the Cuerno-Barabasi Stochastic Continuum Model of Surface Sputtering

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Communications in Theoretical Physics 2012年第7期58卷 165-170页

作者： Oluwole emmanuel Oyewande Department of Physics University of Ibadan

The nonlinear continuum model proposed by Cuerno and Barabasi is the most successful and widely acceptable theoretical description of oblique incidence ion sputtered surfaces to date and is quite robust in its predictions of the time evolution and scaling of interfaces driven by ion bombardment. However, this theory has thus far predicted only ripple topographies and rough surfaces for short and large scales, respectively. As a result, its application to the interpretation and study of nanodots, predicted by Monte Carlo simulations for, and observed in experiments of, oblique incidence sputtering is still unclear and, hence, an open problem. In this paper, we provide a new insight to the theory, within the same length scale, that explains nanodot formation on off-normal incidence sputtered surfaces, among others, and propose ways of observing the predicted topographies of the MC simulations, as well as possible control of the size of the nanodots, in the framework of the Cuerno-Barabasi continuum theory.

关键词： topographic phase diagrams surface nanostructures surface nanodots Cuerno-Barabasi model

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Optimization of adsorbent dose and contact time for the production of jackfruit waste nutrient-enriched biochar

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Waste Disposal and Sustainable Energy 2023年第1期5卷 63-74页

作者： Denis Nsubuga Isa Kabenge Ahamada zziwa Vianney Andrew Yiga Yusufu Mpendo Mawejje Harbert Ronald Kizza Noble Banadda Kerstin D.Wydra Department of Agricultural and Biosystems Engineering Makerere UniversityP.O.Box 7062KampalaUganda Department of Mechanical Engineering Makerere UniversityP.O.Box 7062KampalaUganda Department of Agricultural Production Makerere UniversityP.O.Box 7062KampalaUganda School of Engineering University of British ColumbiaEME242-1137 Alumni AveKelownaBCCanada Plant Production and Climate Change Erfurt University of Applied SciencesLeipziger Straβe 7799085ErfurtGermany

Raw biochar can be enriched with nutrients from digestates through adsorption producing nutrient-enriched *** nutrient-enriched biochar can be used as a soil amendment to support sustainable *** study assessed the effect of adsorbent dose and contact time on the jackfruit waste biochar adsorption of essential nutrients of nitrogen,phosphors and potassium from the *** surface methodology(RSM)using central composite design(CCD)was utilized to optimize the adsorbent dose and contact time during the adsorption *** adsorbent dose of 20–70 mg/g and contact time range of 48–120 h were used in this *** optimal adsorbent dose and contact time were found to be 20 mg/g and 114.6 h,*** corresponding optimum nitrogen,phosphorus and potassium adsorbed were 17.44,20.94,and 21.36 mg/g,*** for the prediction of these values for nitrogen,phosphorus and potassium had R2 values of 0.9801,0.9804 and 0.9843,respectively,and non-significant lack of fit(p<0.05).This indicates the suitability of the models in predicting the adsorption conditions of adsorbent dose and contact time to produce high-quality nutrient-enriched biochar.

关键词： Adsorption Response surface methodology Digestate Nutrient-enriched biochar

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Abiraterone acetate for prostate cancer： a new era ot hormonal therapies

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Asian Journal of Andrology 2011年第5期13卷 663-664页

作者： emmanuel S Antonarakis Johns Hopkins Sidney Kimmel Comprehensive CancerCenter Baltimore MD 21231 USA

Therapies targeting the androgen receptor （AR） axis have constituted the HolyGraft in the management of advanced prostate cancer for seven decades） These hormonal therapies have traditionally taken two main forms： those that suppress gonadal androgen synthesis （e.g., the gonadotropin releasing hormone agonists/antagonists, such as leuprolide）, and those that inhibit the AR directly （e.g., the anti-androgens, such as bicalutamide）. However, although the vast majority of patients with prostate cancer initiaUy respond favorably to androgen-ablative therapies （manifested by tumor regressions and symptomatic improvements）, all patients will eventually develop further disease progression after a median of 18-24 months. This transformed disease state, known as castration-resistant prostate cancer （CRPC）, is invariably fatal.

关键词： Abiraterone hormonal therapies

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Combining active immunotherapy with immune checkpoint blockade for the treatment of advanced prostate cancer

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Asian Journal of Andrology 2012年第4期14卷 520-521页

作者： emmanuel S Antonarakis Johns Hopkins Sidney Kimmel Comprehensive Cancer Center Baltimore MD 21231 USA

Combination immunotherapy is emerging as a promising approach for the treatment of advanced prostate cancer. This research highlight discusses the combination of a PSA-directed pox-viral vaccine and a monoclonal antibody blocking an important immune checkpoint molecule to treat men with metastatic castration- resistant prostate cancer. The results demonstrate feasibility and safety, as well as intriguing clinical responses to this combination therapy.

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