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Assessment of Spatial Distribution and Temporal Trends of Precipitation and Its Extremes over Nigeria

American Journal of Climate Change 2021年第3期10卷 331-352页

作者： moses Owoicho Audu Emmanuel Ejembi Tertsee Igbawua Department of Physics Joseph Sarwuan Tarka University Makurdi Nigeria Department of Natural and Applied Sciences Namibia University of Science and Technology Namibia

This study analyzed the spatial distribution and temporal trends of precipitation and its extremes over Nigeria from 1979-2013 using climate indices, in order to assess climatic extremes in the country. Daily precipitation data used in this study were obtained from Nigeria Meteorological Agency (NIMET), Lagos. The study used climate indices developed by the Expert Team on Climate Change Detection (ETCCDI) for assessing extreme precipitation. Sen’s slope estimator and Mann-Kendall trend test were employed in data analysis. Results revealed that precipitation and its extremes varied spatially across Nigeria. Significant negative trends were observed in most of the precipitation indices for the period under study. Furthermore, significant downward trends were observed in the CWD (Consecutive Wet Day) while the CDD (Consecutive Dry Day) showed significant upward trends in all the regions. These spatial and temporal changes indicate that Nigeria’s climate is trending towards a warmer and drier condition, which could be attributed to global warming-induced climate change;which altered historical rainfall patterns thereby leading to extreme events. The findings of this study have provided useful information in understanding the extreme events that are assumed by the general populace to be normal recurrent events in Nigeria. The results of the analysis of yearly and decadal changes in precipitation totals and extreme values for the last 35 years (1979-2013) suggest the likelihood of severe impacts on water resources, agriculture, and water-sensitive economic activities

关键词： Climate Indices Climate Extreme Climate Change Spatial Pattern Temporal Trends Nigeria

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Evaluation of CHIRPS Satellite Gridded Dataset as an Alternative Rainfall Estimate for Localized Modelling over Uganda

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Atmospheric and Climate Sciences 2021年第4期11卷 797-811页

作者： Ivan Bamweyana moses Musinguzi Lydia Mazzi Kayondo Department of Geomatics and Land Management Makerere University Kampala Uganda

The Ugandan economy is largely dependent on rural-based and rain-fed agriculture. This creates a critical need to understand the rainfall dynamics at the local scale. However, the country has a sternly sparse and unreliable rain gauge network. This research, therefore, sets out to evaluate the use of the CHIRPS satellite gridded dataset as an alternative rainfall estimate for local modelling of rainfall in Uganda. Complete, continuous and reliable in situ station observations for the period between 2012 and 2020 were used for the comparison with CHIRPS satellite data models in the same epoch. Rainfall values within the minimum 5 km and maximum 20 km radii from the in situ stations were extracted at a 5 km interval from the interpolated in situ station surface and the CHIRPS satellite data model for comparison. Results of the 5 km radius were adopted for the evaluation as it’s closer to the optimal rain gauge coverage of 25 km2. They show the R2 = 0.91, NSE = 0.88, PBias = -0.24 and RSR = 0.35. This attests that the CHIRPS satellite gridded datasets provide a good approximation and simulation of

关键词： Spatial Statistics CHIRPS Satellite Gridded Dataset Rainfall Estimates

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Estimation of Ground Deformation in Landslide Prone Areas Using GPS: A Case Study of Bududa, Uganda

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International Journal of Geosciences 2021年第3期12卷 213-232页

作者： Brian Makabayi moses Musinguzi John Richard Otukei Department of Geomatics and Land Management Makerere University Kampala Uganda

Landslides are a frequent phenomenon on mountain Elgon, particularly in Bududa district on the SW side of this extinct shield volcano. Landslides have led to the destruction of property and loss of life we, therefore, need to monitor them. Monitoring how landslides build-up makes it possible to timely evacuate people and build barriers to protect property against damage by landslides. Residents in Bududa have reported cracks developing in the ground and houses. These cracks continue to grow, suggesting a future catastrophic event. Such an event may resemble the 2010 landslide in Bududa, which killed approximately 450 people and destroyed much property. In order to mitigate the consequences of a new landslide as much as possible, we monitored ground motion in Bududa in eleven stations from June 2018 to June 2019. Six-hour session GPS observations were made, and deformation was determined over the observation period, June to September 2018, September to November 2018, November 2018 to February 2019 and February to June 2019. A congruency test was performed to determine how significant the deformation was. It appeared that the ground deformation differed largely at various monitored stations, ranging from 0.004 to 0.076 m, 0.001 to 0.067 m and 0 to 0.078 m in the East, North and vertical directions respectively. The values indicate that most slopes in the district are unstable, particularly in the wet seasons, which implies that future landslides pose a high risk for society.

关键词： Bududa GPS Ground Deformation Natural Hazards

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Desired Characteristics of Non-Oriented Electrical Steels for Use in Next Generation, Energy Efficient, Electrical Power Equipment

Desired Characteristics of Non-Oriented Electrical Steels fo...

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第十届中国钢铁年会暨第六届宝钢学术年会

作者： moses Anthony John Wolfson Centre for Magnetics School of Engineering Cardiff University

Non-oriented electrical steel is by far the most widely used soft magnetic material. It has evolved over the past 100 years and is likely to remain prominent for decades to come despite the challenge for greater market share from emerging materials. However complex ways in which the steels are magnetised in modern electrical equipment are rapidly becoming more common in many applications so it is useful to review the parameters which control their magnetic properties and consider the growing need for optimising the magnetic properties under more challenging magnetisation conditions such as high flux density, rotational magnetisation or non-sinusoidal flux density. The presentation reviews the reasons for the dominating influence of composition（silicon content）, grain size, internal stress, impurities, sheet thickness and texture. Although the generality of the well know method of analysing losses in terms of hysteresis, classical eddy current and excess losses is often questioned today, it is still a useful approach for attempting to understand the factors influencing the losses in non-oriented steels. However, the effectiveness of the approach under these more challenging magnetising conditions is discussed. It is likely that users will demand far more versatility from non-oriented materials in the future in terms of effective operation under wide ranges of magnetisation conditions which make the relevance of established Standard ways of grading materials at a fixed frequency and flux density questionable when selecting best material for a given purpose. The inference of this situation on material development is briefly discussed. Finally the possible impact of future developments in controlled textures or resistivity gradients through the sheet thickness on the performance of energy efficient non-oriented materials operating on under more complex magnetising conditions is considered.

关键词： magnetic materials electrical steel non-oriented silicon steel

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Brevipedicelones D and E,Two C-O-C Flavonoid Dimmers from the Leaves of Garcinia brevipedicellata and Anti-onchocercal Activity

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Natural Products and Bioprospecting 2019年第1期9卷 61-68页

作者： Mirabel Akongwi Anastasie ETih Kennedy D.Nyongbela moses Samje Raphael T.Ghogomu Bernard Bodo Department of Organic Chemistry Faculty of ScienceUniversity of Yaounde 1P.O.Box 812YaoundeCameroon Pharmacochemistry Research Laboratory Department of ChemistryFaculty of ScienceUniversity of BueaP.O.Box 63BueaSouth West RegionCameroon Faculty of Science ANDI Centre of Excellence on Onchocerciasis ResearchUniversity of BueaP.O.Box 63BueaSouth West RegionCameroon Laboratoire de Chimie des Substances Naturelles Muse´um National d’Histoire Naturelle63 Rue Buffon75005 ParisFrance

A novel isoflavone–chromone flavonoid C–O–C dimmer,brevipedicelone D(1),along with one new C–O–C biflavonoid derivative,brevipedicelone E(2),were isolated from the ethyl acetate extract of the leaves of Garcinia brevipedicellata,a medicinal plant used in folk medicine in parts of *** structures were elucidated by extensive spectroscopic techniques,including 1D-and 2D-NMR,MS experiments,as well as comparing their spectral data with those of known ***-onchocercal screening of 1 showed moderate inhibition of adult worm motility of Onchocerca ochengi by 60%at the highest concentration(20 μg/mL)and inhibited motility of both the juvenile worms of *** and Loa loa by 90%at this same concentration.

关键词： Garcinia brevipedicellata Brevipedicelone Anti-onchocercal activity

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Estimation of Ground Vertical Displacement in Landslide Prone Areas Using PS-InSAR. A Case Study of Bududa, Uganda

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International Journal of Geosciences 2021年第4期12卷 347-380页

作者： Brian Makabayi moses Musinguzi John Richard Otukei Department of Geomatics and Land Management Makerere University Kampala Uganda

Estimation of ground displacement in landslide susceptible regions is very critical to understanding how landslides develop. The knowledge of ground displacement rates and magnitudes helps plan for the safety of the people and infrastructure. The early detection of landslides in Bududa is still a challenge due to the limited technology, hard to access, and a need for an affordable technique that can monitor a wide area continuously. In recent studies, the use of Persistent Scatterer Interferometry Synthetic Aperture Radar (PS-InSAR) has provided vital information on landslide monitoring through the measurement of ground displacement. In this study, Synthetic Aperture Radar (SAR) band C series of Sentinel 1-A and 1-B Satellite images were acquired between 2019 and 2020 along ascending and descending orbit paths. The Line of Sight Sight (LOS) displacement was determined for both satellite tracks, and then the LOS displacement was projected to the vertical direction. The PS-InSAR derived vertical displacement was then compared with GPS vertical displacement magnitudes over three GPS stations in the area. It was observed that vertical displacement velocity reached 20 cm/yr in Mountain Elgon. This displacement rate showed that there are points in the region that are highly unstable. The displacement velocity and magnitude in Bududa reached 6 cm/yr and 13 cm in two years. This rate and magnitude showed that Bududa is highly unstable compared with displacement velocities and magnitudes in landslide susceptible areas globally. The displacement was generally subsidence over the observation period. The vertical displacement estimated by PS-InSAR was comparable with GPS based on the estimated RMSE. The vertical displacement was highest at slopes between 32

关键词： Bududa Landslides PS-InSAR Vertical Displacement

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Support induced phase engineering toward superior electrocatalyst

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Nano Research 2022年第3期15卷 1831-1837页

作者： Beibei Sheng Dengfeng Cao Hongwei Shou Oyawale Adetunji moses Wenjie Xu Yujian Xia Yuzhu Zhou Huijuan Wang Ping Wan Shuang Zhu Wangsheng Chu Xiaojun Wu Shuangming Chen Li Song National Synchrotron Radiation Laboratory CAS Center for Excellence in NanoscienceUniversity of Science and Technology of ChinaHefei 230026China Hefei National Laboratory for Physical Sciences at the Microscales Department of Materials Sciences and EngineeringUniversity of Science and Technology of ChinaHefei 230026China Experimental Center of Engineering and Material Science University of Science and Technology of ChinaHefei 230026China Materials Interfaces Center Shenzhen Institutes of Advanced TechnologyChinese Academy of SciencesShenzhen 440305China Institute of Energy Hefei Comprehensive Nation Science CenterHefei 230031China

The phase transformation of catalysts has been extensively observed in heterogeneous catalytic reactions that hinder the long cycling catalysis,and it remains a big challenge to precisely control the active phase during the complex conditions in electrochemical ***,we theoretically predict that carbon-based support could achieve the phase engineering regulation of catalysts by suppressing specific phase *** single-walled carbon nanotube(SWCNT)as typical support,combined with calculated E-pH(Pourbaix)diagram and advanced synchrotron-based characterizations technologies prove there are two different active phases source from cobalt selenide which demonstrate that the feasibility of using support effect regulating the potential advantageous ***,it is worth noting that the phase engineering derived Co_(3)O_(4)-SWCNT exhibits a low overpotential of 201 mV for delivering the current density of 10 mA/cm^(2)in electrocatalytic oxygen evolution reaction(OER).Also,it reaches a record current density of 529 mA/cm^(2)at 1.63 V(***)in the electrocatalytic urea oxidation reaction(UOR),overwhelming most previously reported catalysts.

关键词： phase engineering support synchrotron radiation characterization oxygen evolution reaction(OER) urea oxidation reaction(UOR)

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Mathematical modeling of COVID-19 infection dynamics in Ghana: Impact evaluation of integrated government and individual level interventions

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Infectious Disease Modelling 2021年第1期6卷 381-397页

作者： Duah Dwomoh Samuel Iddi Bright Adu Justice moses Aheto Kojo Mensah Sedzro Julius Fobil Samuel Bosomprah Department of Biostatistics School of Public HealthCollege of Health SciencesUniversity of GhanaLegonAccraGreater AccraGhana Department of Statistics University of GhanaLegonAccraGreater AccraGhana Noguchi Memorial Institute for Medical Research Department of ImmunologyCollege of Health SciencesUniversity of GhanaLegonGreater AccraGhana Department of Biological Environmental and Occupational HealthSchool of Public HealthCollege of Health SciencesUniversity of GhanaLegonAccraGreater AccraGhana

The raging COVID-19 pandemic is arguably the most important threat to global health *** there is currently a vaccine,preventive measures have been proposed to reduce the spread of infection but the efficacy of these interventions,and their likely impact on the number of COVID-19 infections is *** this study,we proposed the SEIQHRS model(susceptible-exposed-infectious-quarantine-hospitalized-recovered-susceptible)model that predicts the trajectory of the epidemic to help plan an effective control strategy for COVID-19 in *** provided a short-term forecast of the early phase of the epidemic trajectory in Ghana using the generalized growth *** estimated the effective basic Reproductive number Re in real-time using three different estimation procedures and simulated worse case epidemic scenarios and the impact of integrated individual and government interventions on the epidemic in the long term using compartmental *** maximum likelihood estimates of Re and the corresponding 95%confidence interval was 2.04[95%CI:1.82e2.27;12th March-7th April 2020].The Re estimate using the exponential growth method was 2.11[95%CI:2.00e2.24]within the same *** Re estimate using time-dependent(TD)method showed a gradual decline of the Effective Reproductive Number since March 12,2020 when the first 2 index cases were recorded but the rate of transmission remains high(TD:Re=2.52;95%CI:[1.87e3.49]).The current estimate of Re based on the TD method is 1.74[95%CI:1.41 e2.10;(13th May 2020)]but with comprehensive integrated government and individual level interventions,the Re could reduce to 0.5 which is an indication of the epidemic dying out in the general *** results showed that enhanced government and individual-level interventions and the intensity of media coverage could have a substantial effect on suppressing transmission of new COVID-19 cases and reduced death rates in Ghana until such a time that a potent vaccine or drug is di

关键词： COVID-19 Mathematical modeling Intervention Effective reproductive number Infectious disease Differential equations

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Variations in Patch Use by Ruminant and Non-ruminant Herbivores in a Tropical Wildlife Reserve, Ghana

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Journal of Resources and Ecology 2022年第6期13卷 1143-1151页

作者： Godfred BEMPAH Joseph KAFRIFA moses ANARTEY LU Changhu College of Forestry Nanjing Forestry UniversityNanjing 210037China Department of Conservation Biology and Entomology University of Cape CoastCape Coast CC-145-8669Ghana Department of Animal Science University of Energy and Natural ResourcesSunyani BS-0061-2164Ghana College of Biology and the Environment Nanjing Forestry UniversityNanjing 210037China

Food processing and consumption by herbivores are affected differently by the availability of forage quality and quantity per unit of time. This demonstrates the “Allometric response concept”, and it is considered a significant determinant in habitat use for foraging by grazers. The relevance of this approach has comprehensively been applied to herbivores of different body sizes, but little is known about its demonstration to explain patch use in herbivores with different digestive physiology and body size. We explain the use of patches by grazing herbivores of different digestive physiology and body sizes, Hippopotamus amphibius(hippopotamus, mega non-ruminant) and cattle(ruminant), by integrating foraging relationship herbivores. We analysed the significant relationships between species dropping densities and environmental variables across forty-eight 100 m×100 m plots in Bui National Park,Ghana, during the wet and dry seasons. We found that both species utilised areas closer to the river in the wet season, but the H. amphibius foraged further away from the river during the dry season. Sward height also determined patch use by both species, with the H. amphibius utilising shorter swards than the cattle. Considering the quality of food resources, the study revealed that patch selection of ruminants(cattle) was significantly influenced by nitrogen content. In contrast, acidic detergent fibre content was positively related to non-ruminant species(***). The high seasonal effect of sward height and food quality on patch use is primarily due to the species digestive physiology and body size of hippopotamus and cattle at the Bui National Park.

关键词： digestive physiology herbivore mammals foraging hippopotamus

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A Field Study in the Status and Threats of Cultivation in Kimana and Ilchalai Swamps in Amboseli Dispersal Area, Kenya

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Natural Resources 2011年第4期2卷 197-211页

作者： moses Makonjio Okello John M. Kioko 不详

The scarcity of water and dependence of local communities on wetlands for resources and services is a common occurrence in dry rangelands such as Amboseli in Kenya. There are only a few swamps outside Amboseli National Park available to the Maasai, livestock and wildlife. Such swamps may disappear in the near future because of conversion to cultivation. This study established the current size and threats to Kimana and Ilchalai near Amboseli National Park. Swamps were regularly used by over 15 large mammal species among them elephants, buffalo, wildebeest, zebra, gazelles and hippopoatums. However, only 15.7% of Kimana Swamp and 36.1% of Ilchalai Swamp remained unconverted to cultivation, with the rest of the remaining swamp area converted to agriculture. Cultivation was mainly done by non–Maasai land leasers, and for mainly commercial purposes. Swamps were converted because of adequate and free water, cheap lease fee, and their fertile soils. Although concerned with swamp conversion, most cultivators were ready to expand cultivation in other swamps. These findings demonstrate how unsustainable resource use and swamp conversion can seriously threaten critical resources for local livelihoods and wildlife conservation.

关键词： Amboseli Ecosystem Irrigated Agriculture Kenya Maasai Livelihoods Resource Conservation Swamps

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