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A regional GNSS-VTEC model over Nigeria using neural networks： A novel approach

Geodesy and Geodynamics 2016年第1期7卷 19-31页

作者： Daniel Okoh Oluwafisavo Owolabi Christovher Ekechukwu Olanike Folarin Gila Arhiwo joseph agbo Segun Bolaji Babatunde Rabiu NASRDA Center for Atmospheric Research Kogi State University Anyigba Campus Nigeria Ionospheric & Space Physics Laboratory Department of Physics University of Lagos Nigeria Department of Physics University of Calabar Nigeria Department of Physics Federal University of Agriculture Makurdi Nigeria Department of Surveying & Geo-informatics Nnamdi Azikiwe University Awka Nigeria

A neural network model of the Global Navigation Satellite System - vertical total electron content （GNSS-VTEC） over Nigeria is developed. A new approach that has been utilized in this work is the consideration of the International Reference Ionosphere＇s （IRI＇s） critical plasma frequency （foF2） parameter as an additional neuron for the network＇s input layer. The work also explores the effects of using various other input layer neurons like distur- bance storm time （DST） and sunspot number. All available GNSS data from the Nigerian Permanent GNSS Network （NIGNET） were used, and these cover the period from 2011 to 2015, for 14 stations. Asides increasing the learning accuracy of the networks, the inclusion of the IRI＇s foF2 parameter as an input neuron is ideal for making the networks to learn long-term solar cycle variations. This is important especially for regions, like in this work, where the GNSS data is available for less than the period of a solar cycle. The neural network model developed in this work has been tested for time-varying and spatial per- formances. The latest 10% of the GNSS observations from each of the stations were used to test the forecasting ability of the networks, while data from 2 of the stations were entirely used for spatial performance testing. The results show that root-mean-squared-errors were generally less than 8.5 TEC units for all modes of testing performed using the optimal network. When compared to other models, the model developed in this work was observed to reduce the prediction errors to about half those of the NeQuick and the IRI model.

关键词： Global Navigation Satellite System(GNSS) ionosphereTotal electron content (TEC)Nigerian permanent GNSS network(NIGNET)Neural networkInternational reference ionosphere(IRI)

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Antimotility effects of extracts and fractions of Eastern Nigeria mistletoe(Loranthus micranthus Linn)

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Asian Pacific Journal of Tropical Medicine 2012年第7期5卷 556-560页

作者： Patience O Osadebe Chika C Abba Matthias O agbo Department of Pharmaceutical and Medicinal Chemistry University of NigeriaNsukkaEnugu StateNigeria

Objective:To evaluate the antimotility activity of Eastern Nigerian mistletoe[Loranthus micranthus（***） Linn]parasitic on six different host trees *** nitida,Persia americana,Kola accuminata,Irvingia gabonensis,Citrus simensis and Pentacletra macrophylla （***）.Methods:The antimotility of the methanol extracts and solvent fractions were evaluated in castor oil induced diarrheoa in ***:The methanol extracts（200 mg/kg, i.p.） inhibited defeacation significantly（P 5 exhibited inhibitory activity which was comparable to loperamide（73.3%）. Conclusions:The methanol extract of L micranthus parasitic on *** exhibits higher antimotility activity that other *** solvent fractions could serve as source of novel antimotility agents.

关键词： Loranthus micranthus Fractination Gastrointestinal transit Atropine

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Heterosis and combining ability in cucumber(Cucumis sativus L.)

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Information Processing in Agriculture 2019年第1期6卷 150-157页

作者： Chikezie Onuora Ene Peter Ejimofor Ogbonna Christian Ugwu agbo Uchechukwu Paschal Chukwudi Department of Crop Science University of NigeriaNsukka 410001Nigeria

The objective of this work was to evaluate four parental lines of cucumber which included:‘Zeina’(Zna),‘Beit Alpha’(BA),‘Straight 8’(Strght 8)and‘Calypso’(Capso)and six F1s generated by diallel cross,using randomized complete block design with three replications to study heterosis and combining ability for yield and yield component *** heterosis showed that cross‘ZnaCapso’had the highest Better Parent(BP)heterosis in total fruit yield/ha while‘BACapso’had the highest Mid Parent(MP)heterosis in the same *** general(GCA)and specific(SCA)combining ability variances were obtained in all the traits implying that both the additive and non-additive gene effects operated in the genetic expression of the *** magnitude of GCA and SCA variances indicated preponderance of additive gene action for all the traits.‘Beit Alpha’and‘Straight 8’are best general combiners while‘BACapso’and‘CapsoStrght 8’were the best specific combiners for total fruit yield.

关键词： Cucumber Hybrid vigour Half diallel crosses GCA SCA

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Impact of the emigration of nurses on health care delivery system in selected hospitals,Benin‑City,Edo State,Nigeria

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Journal of Integrative Nursing 2020年第3期2卷 110-115页

作者： Olaolorunpo OLORUNFEMI David Idenyi agbo Omotayo Mercy OLORUNFEMI Esther OdoghoOKUPAPAT Department of Medical Surgical Nursing School of NursingUniversity of Benin Teaching Hospital Department of Measurement and Evaluation University of Benin Teaching Hospital Staff School Department of Perioperative Nursing School of Postbasic Nursing StudiesUniversity of Benin Teaching HospitalBenin-cityEdo StateNigeria

Background:Globally,there is a high demand for nurses,resulting in migration from low‑to high‑income *** emigration of nurses is the act of leaving one's own country to settle permanently in another country,leading to a shortage in the number of nurses in their home ***,this study aims to assess the impact of the emigration of nurses on the health‑care delivery system in *** and Methods:A descriptive cross‑sectional survey was conducted with a stratified sampling technique to select 270 nurses from three selected hospitals in Benin‑city Edo state.A self‑structured questionnaire with open and Likert scale questions were used as an instrument to assess the Impact of the Emigration of nurses on the Health Care Delivery *** collected were analyzed using tables,percentages,means,standard deviation and t‑***:The result showed a mean score of 1.59±0.92 impacts of the emigration of nurses on health‑care delivery system and identified how to reduce *** study also showed that there is no significant difference between gender and reason for emigration among nurses(t=3.84,P≤0.001).Conclusion:The emigration of nurses is severely affecting the health care delivery system in the ***,the Nursing and Midwifery Council of Nigeria gave the directive for training schools to increase their training capacity and number of students’intake to cushion the effect,and this study shows that this palliative can only be a short time measure,and however will encourage more nurses traveling abroad on the long ***,the hospital managers and government should provide a conducive working environment,better remuneration,attractive retirement benefit,and other incentives as a push in factor for nurses to stay back in their home countries.

关键词： Emigration health‑care system migration Nigeria nurses

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Issues in Financial Markets’Development in Sub-Saharan Africa:Lessons From Developed Economies

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Management Studies 2021年第2期9卷 124-136页

作者： Elias Igwebuike agbo Sergius Nwannebuike Udeh Godfrey Okoye University Ugwuomu-NikeEnuguNigeria

For some time now,development of financial markets in developing countries of the world has been saddled with a lot of ***,observations from many studies showed contradictory views which have made debates on the subject matter *** view of this,the general objective of this study is to examine financial and stock market developmental issues in developing African *** specifically intends to highlight strategies to strengthen financial and stock markets in African countries,among *** study adopted table content analysis and descriptive statistics in its *** study discovered that in spite of all the gains derivable from financial market development,the intensity of financial sector reforms implemented in some developing countries has not brought about a reasonable increase in the size and depth of their financial systems,among *** implication of this is that capital market development in these developing countries would continue to suffer setbacks with their attendant consequences on economic *** study concluded that the presence of strong and virile financial and stock markets cannot be overlooked in any *** therefore recommended,amidst others,the promotion of institutional investors as well as development of appropriate business and investor friendly policies.

关键词： finance stock market developmental issues African countries

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Influence of surface modified mixed metal oxide nanoparticles on the electrochemical and mechanical properties of polyurethane matrix

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Frontiers of Chemical Science and Engineering 2023年第1期17卷 1-14页

作者： joseph Raj Xavier Department of Chemistry Saveetha School of EngineeringSaveetha Institute of Medical and Technical SciencesChennai-602105India

Newly synthesized functional nanoparticles,3-amino-1,2,4-triazole(ATA)/SiO_(2)—TiO_(2)were introduced to the polyurethane(PU)*** techniques were used to investigate the barrier properties of the synthesized PU—ATA/SiO_(2)—TiO_(2)nanocomposite coated steel *** natural seawater,electrochemical impedance spectroscopy experiments indicated outstanding protective behaviour for the PU—ATA/SiO_(2)—TiO_(2)coated *** coating resistance(Rcoat)of PU—ATA/SiO_(2)—TiO_(2)was determined to be 2956.90 kΩ·cm^(−2).The Rcoat of the PU—ATA/SiO_(2)—TiO_(2)nanocomposite coating was found to be over 50%higher than the PU *** current measured along the scratched surface of the PU—ATA/SiO_(2)—TiO_(2)coating was found to be very low(1.65 nA).The enhanced ATA/SiO_(2)—TiO_(2)nanoparticles inhibited the entry of electrolytes into the coating interface,as revealed by scanning electron microscopy/energy dispersive X-ray spectroscopy and X-ray diffraction analysis of the degradation *** contact angle testing validated the hydrophobic nature of the PU—ATA/SiO_(2)—TiO_(2)coating(θ=115.4°).When the concentration of ATA/SiO_(2)—TiO_(2)nanoparticles was 2 wt%,dynamic mechanical analysis revealed better mechanical ***,the newly synthesised PU—ATA/SiO_(2)—TiO_(2)nanocomposite provided excellent barrier and mechanical properties due to the addition of ATA/SiO_(2)—TiO_(2)nanoparticles to the polyurethane,which inhibited material degradation and aided in the prolongation of the coated steel’s life.

关键词： SiO_(2)/TiO_(2)nanoparticle nanocomposite coatings dynamic mechanical analysis electrochemical techniques corrosion colloids and interfaces

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Tax Policy and Planning:Lessons From Developed Countries

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Management Studies 2021年第4期9卷 251-269页

作者： Elias Igwebuike agbo Sergius Nwannebuike Udeh Godfrey Okoye University Ugwuomu-NikeEnuguNigeria

One of the fundamental issues in developing countries is how to evolve tax policies that can generate sufficient revenue for government *** upon the above,this study examined tax policies and planning in developing sub-Saharan African *** adopted table content analysis and descriptive statistics in its *** study observed that aggressive tax planning which the Multi-National Corporations execute through royalty payment,interest payment,strategic transfer pricing and treaty shopping,among others,has caused countries around the globe huge revenue losses annually and has become a matter of serious concern to both the developed and developing *** implication of this is that achievement of objectives of tax policies and their reforms will remain a mirage in sub-Saharan African *** study concluded that the prevalence of illicit financial outflows in the form of tax evasion and avoidance in the guise of aggressive tax planning by multinational corporations,however,makes Africa’s tax policies *** was recommended that the Organization for Economic Corporation and Development,and the G-20 should involve developing countries in the Base Erosion and Profit Shifting project as they are the worst victims of these activities.

关键词： tax policy aggressive tax planning developing countries Africa

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On Two Classes of Finite Inseparable p-Groups

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Acta Mathematica Sinica,English Series 2015年第7期31卷 1203-1214页

作者： joseph KIRTL Department of Mathematics Marist College

A finite group is inseparable, it does not split over any proper nontrivial normal subgroup; that is, if it has no nontrivial semidirect product decompositions. This paper investigates two classes of finite inseparabl... 详细信息

关键词： p-group inseparable splitting

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Toll-like receptor signaling in hematopoietic homeostasis and the pathogenesis of hematologic diseases

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Frontiers of Medicine 2015年第3期9卷 288-303页

作者： joseph Cannova Biochemistry and Molecular Biology Program Loyola University Chicago Maywood IL 60153 USA Stritch School of Medicine Loyo& University Chicago Maywood IL 60153 USA Oncology Institute Loyola University Chicago Maywood IL 60153 USA Department of Pathology Loyola University Chicago Maywood IL 60153 USA Department of Biology Loyola University Chicago Chicago IL 60660 USA Department of Molecular and Cellular Physiology Loyola University Chicago Maywood IL 60153 USA

Toll-like receptors （TLRs）, which are found in innate immune cells, are essential mediators of rapid inflammatory responses and appropriate T-cell activation in response to infection and tissue damage. Accumulating evidence suggests that TLR signaling is involved in normal hematopoiesis and specific hematologic pathologies. Particular TLRs and their downstream signaling mediators are expressed not only in terminally differentiated innate immune cells but also in early hematopoietic progenitors. Sterile activation of TLR signaling is required to generate early embryonic hematopoietic progenitor cells. In adult animals, TLR signaling directly or indirectly promotes differentiation of myeloid cells at the expense of that of lymphoid cells and the self renewal of hematopoietic stem cells during infection and tissue damage. Activating mutations of the MyD88 gene, which codes for a key adaptor involved in TLR signaling, are commonly detected in B-cell lymphomas and other B-cell hematopathologies. Dysregulated TLR signaling contributes to the pathogenesis of many hematopoietic disorders, including bone marrow failure, myelodysplastic syndrome, and acute myeloid leukemia. Complete elucidation of the molecular mechanisms by which TLR signaling mediates the regulation of both normal and pathogenic hematopoiesis will prove valuable to the development of targeted therapies and strategies for improved treatment of hematopoietic disorders.

关键词： TLR MyD88 hematopoiesis bone marrow failure leukemia myelodysplastic syndrome

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Modeling some long-term implications of CO_2 fertilization for global forests and forest industries

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Forest Ecosystems 2016年第1期3卷 13-25页

作者： joseph Buongiorno Department of Forest and Wildlife Ecology University of Wisconsin-Madison

Background： This paper explored the long-term, ceteris-paribus effects of potential CO2 fertilization on the global forest sector. Based on the findings of Norby et al. （PNAS 2005, 102（50）） about forest response to elevated [CO2]. Methods： Forest productivity was increased in the Global Forest Products Model （GFPM） in proportion to the rising [CO2] projected in the IPCC scenario A1B, A2, and 132. Projections of the forest area and forest stock and of the production, consumption, prices, and trade of products ranging from fuelwood to paper and paperboard were obtained with the GFPM for each scenario, with and without CO2 fertilization beginning in 2011 and up to 2065. Results： CO2 fertilization increased wood supply, leading to lower wood prices which in turn induced modest lower prices of end products and higher global consumption. However, production and value added in industries decreased in some regions due to the relative competitive advantages and to the varying regional effects of CO2 fertilization. Conclusion： The main effect of CO2 fertilization was to raise the level of the world forest stock in 2065 by 9 to 10 % for scenarios A2 and B2 and by 20 % for scenario A1B. The rise in forest stock induced by fertilization was in part counteracted by its stimulation of the wood supply which resulted in lower wood prices and increased harvests.

关键词： CO2 fertilization Climate change Prices Supply Demand International trade

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