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Evaluation of Antiplasmodial Effect of Methanol Leaf Extract and Fractions of Eucalyptus camadulensis (Denhn) in Albino Wistar Mice

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American Journal of Plant Sciences 2023年第6期14卷 662-676页

作者： Amarachi Akachukwu Moses Ikegbunam emmanuel enyi Theresa Osarunwese Ifeyinwa Onochie-Igbinedion Harrison Abone Dorothy Ezeagwuna Joy Nnanna Chibueze Ihekwereme Chukwuemeka Nworu Department of Pharmacology and Toxicology Nnamdi Azikiwe University Awka Nigeria Department of Pharmaceutical Microbiology and Biotechnology Nnamdi Azikiwe University Awka Nigeria Molecular Research Foundation for Students and Scientists Nnamdi Azikiwe University Awka Nigeria Department of Parasitology and Entomology Nnamdi Azikiwe University Awka Nigeria Department of Pharmacology and Toxicology University of Nigeria Nsukka Nigeria

Nigeria is one of the malaria-endemic countries, where the treatment of malaria has relied heavily on natural and traditional medicines. This study was designed to investigate and ascertain the preference of Eucalyptus camaldulensis in treating malaria using three standard models among local herbalists. Extraction was carried out on the leaves of Eucalyptus camadulensis using methanol. The methanol crude extract and other solvent fractions obtained were used for analysis. An acute toxicity test (LD50) was carried out using Lorke’s Method. The extract and its fractions were screened for phytochemical constituents using standard procedures. Different doses of the methanol crude extract (250 mg/kg, 500 mg/kg, and 1000 mg/kg) and other solvent fractions (250 mg/kg, 500 mg/kg) were assessed for their antiplasmodial property using the Suppressive, Curative, and Prophylactic models on different days. One hundred and eighty grams (18% w/w) of the extract were recovered from 1000 g of powdered leaves. The weight of fractions and their yields calculated from 50 g crude extract are n-hexane fraction (3.45 g, 6.9%), ethylacetate fraction (11.65 g, 23.3%), and butanol (7.84 g, 15.68%). The result of the acute toxicity test showed that the lethal dose of the plant was above 5000 mg/kg. For the crude extract, the 1000 mg/kg dose had the highest percentage of parasitemia suppression of 97.3%, 95.30%, and 75.97% in the curative, suppressive, and prophylactic models, respectively. The fractions exhibited a significant chemosuppressive effect when compared with the negative control, with the butanol fraction (500 mg/kg) showing a higher percentage suppression. The findings in this study justify the use of this plant in traditional medicine for the management of malaria fever and tally with its folkloric use. However, more research is needed to establish the functions of the constituents in relation to antiplasmodial activity.

关键词： Eucalyptus camadulensis Antiplasmodial

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HIV-1 RNA Viral Load, CD4 Count and Some Haematological Parameters of People Living with HIV in the Enugu Metropolis

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World Journal of AIDS 2023年第2期13卷 57-69页

作者： Izuchukwu Ibeagha Evelyn Ada Kyrian-Ogbonna Felix Emelike Ekene Ibeagha emmanuel enyi Theresa Osarunwese Ifeyinwa Onochie-Igbinedion Harrison Abone Dorothy Ezeagwuna Chinwe Chukwuka Moses Ikegbunam Anti-Retroviral Therapy (ART) Laboratory University of Nigeria Teaching Hospital Ituku Enugu Nigeria APIN Public Health Initiative Makurdi Nigeria Department of Applied Microbiology and Brewing Nnamdi Azikiwe University Awka Nigeria Medical Laboratory Department Ambrose Alli University Ekpoma Nigeria Center for Clinical Care and Clinical Research of Nigeria (CCRN) Makurdi Nigeria Department of Pharmaceutical Microbiology and Biotechnology Nnamdi Azikiwe University Awka Nigeria Department of Parasitology and Entomology Nnamdi Azikiwe University Awka Nigeria Molecular Research Foundation for Students and Scientists (MRFSS) Nnamdi Azikiwe University Awka Nigeria

Background: It is widely known that the human immune-deficiency virus (HIV) induces biochemical and physiological changes in affected persons. Consequently, the overall aim of this study was to evaluate the HIV-1 RNA viral load, CD4 count, and certain haematological parameters among HIV treatment-na?ve subjects in the Enugu metropolis of Nigeria. Materials and Methods: A total of 252 HIV-infected, ART-native subjects (≥18) attending the University of Nigeria Teaching Hospital (UNTH) in Ituku-Ozalla, Enugu were recruited for this study and were made up of 157 (62.3%) females and 95 (37.7%) males. A total of 250 HIV-negative subjects were used as control subjects (100 males and 150 females). Blood samples were collected from all the participants and their HIV-1 status was confirmed by an immunoblot confirmatory test. Their haematological parameters and CD4 count were evaluated, while the HIV-1 viral load was only assessed on confirmed HIV-positive subjects. Results: There was female predominance (62.3%) among these HIV-positive subjects. The mean age of HIV-positive subjects was 39.16 ± 10.08 years while the mean age of the control subjects was 34.8 ± 8.6 years. The age group of 31 - 40 years (102/252 (40.5%)) constituted most of the test subjects. The total white blood cells (TWBC) (6.05 ± 5.46), lymphocyte counts (36 ± 14), haemoglobin concentrations (Hb) (9.85 ± 7.36) and the CD4 counts (242 ± 228) of the HIV-infected subjects showed a significant difference when compared with their control counterpart values of TWBC (4.5 ± 0.568), lymphocytes (39.67 ± 8.2), Hb (13.48 ± 1.5), and CD4 counts (807 ± 249) (p 0.05). Anaemia, lymphocytopenia, and thrombocytopenia were the haematological abnormalities seen in the HIV-positive subjects. HIV viral load correlated with haemoglobin concentration, CD4 count, lymphocyte count, and neutrophil count (p Conclusion: Prognostic factors, such as haemoglobin concentrations, CD4 counts, lymphocyte counts, and neutrophil counts can be

关键词： HIV-1 RNA CD4 Count Haematological Parameters

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Comparison of Four Diagnostic Tests Methods for the Detection of Dengue Virus Non-Structural-1 Antigen and IgM/IgG Antibodies

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Journal of Biosciences and Medicines 2022年第5期10卷 179-190页

作者： Moses N. Ikegbunam Ifeyinwa T.O. Onochie-Igbinedion Nzube F. Ekpunobi Abone Harrison enyi emmanuel Simon Nkpeh Ushie Micheal U. Adiukwu Charles O. Esimone Department of Pharmaceutical Microbiology and Biotechnology Nnamdi Azikiwe University Awka Nigeria Molecular Research Foundation for Students and Scientists Nnamdi Azikiwe University Awka Nigeria Department of Medical Microbiology Nnamdi Azikiwe University Awka Nigeria Department of Pharmaceutics University of Nigeria Nsukka (UNN) Nsukka Nigeria

Objectives: Dengue virus (DENV) infection is a mosquito-borne disease that stands out as one of the major public health issues and has a wide-ranging geographical distribution throughout the tropics and subtropics. The general alarming increase in the number of cases over the last two decades can be attributed to an extent by the change in national practices to keeping records and reporting dengue to the Ministries of Health, and WHO. Dengue diagnosis is routinely carried out by detection of dengue virus (DENV) antigen NS1 (Non-structural Antigen 1) and/or anti-DENV IgM/IgG antibodies using enzyme-linked immunosorbent assays (ELISAs) and rapid diagnostic tests (RDTs). This study compared the performance of three RDTs and one ELISA used for dengue diagnosis in southeastern, Nigeria. Design: This study adopted a cross-sectional design that included prospective hospital-based surveillance of cases among febrile participants attending two major health facilities within the southeastern region of Nigeria. In this study, 338 HIV-infected participants from two teaching hospitals in Nigeria’s southeast were systematically tested for Dengue with four methods: NS1 RDT, IgG RDT, IgM RDT, and NS1 ELISA. Their specificities and sensitivities were compared, as well as their level of concordance. Their respective performances were also evaluated using the Receivers Operational curve (ROC). Results: Out of the 338 patients, the dengue prevalence from the four dengue diagnostic methods Dengue virus NS1 ELISA, NS1 RDT, IgM and IgG seropositivity were 8.9%, 0.6%, 5.6%, and 8.0%, respectively. The Dengue IgM RDT test indicated 36.8% sensitivity, 92.8% specificity, the IgG anti-dengue specific test indicated 29.6% sensitivity, 92.9% specificity and the dengue NS1 RDT test indicated 3.3% sensitivity, 99.4% specificity when compared with the Dengue NSI Elisa test method as a reference method. Conclusion: The use of NSI ELISA for DENV diagnosis showed good performance and the RDTs showed,

关键词： Dengue Virus Diagnosis Methods Comparison Performance Southeastern Nigeria

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3D TEM study on hollow α-Fe2O3 nanostructures and nanorings

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Progress in Natural Science:Materials International 2019年第6期29卷 685-689页

作者： Ming Lin enyi Ye Jia Zhang Institute of Materials Research and Engineering A*STAR (Agency for Science Technology and Research) Institute of High Performance Computing A*STAR (Agency for Science Technology and Research)

Controlled synthesis of hollow structures with non-spherical holes is significant in fabricating nanomaterials with well-defined geometries and specific catalytic and electrochemical properties. Here we report the synthesis of uniform hexagonal bipyramid hematite(α-Fe2O3) nanoparticles with hollow and faceted interior via directional etching process in solution. The delicate hollow structures were investigated by electron tomography and growth mechanism was revealed unambiguously. The three-dimensional visualization demonstrates the outside surfaces of hematite particles are enclosed by six {104} and twelve {113} planes, due to the stabilizing effect of the F-anions on the exposed surfaces. The concurrent etching process is a reverse process of crystal growth and leads to the dissolution occurring at the edges and tips of the hexagonal bipyramid particles, resulting in the perforated crystals with exposed {102} internal facets or overetched nanorings with hexagonal *** nanoscale growth and etching process still strictly follows the bulk crystal growth mechanism, thus shedding light on the synthesis of other nanoparticle with controlled morphologies and porous structures.

关键词： Tomography Hexagonal bipyramid Dissolution Facet control Phase transformation

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SFD-AGC algorithm with ADC digitalizing bit fully utilized and stable PAR

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The Journal of China Universities of Posts and Telecommunications 2017年第5期24卷 8-15页

作者： Wang Jie Hu Xiaoguang Guan enyi Ding Zhushun Yao Yidong Li Wen School of Automation Science and Electrical Engineering Beihang University Beijing 100191 China Beijing Institute of Aerospace Control Devices Beijing 100039 China

Aiming at making full use of analog to digital converter （ADC） digitalizing bit without oversaturation while keeping peak to average ratio （PAR） stable, this paper puts forward a new segmented full-digital （SFD）-automatic gain control （AGC） algorithm for a new long term evolution （LTE） communication system. Segmented digital gain control strategy is adopted to adjust the gain by only one step based on detected power status. Whether the gain needs to be adjusted is determined by current signal state derived from the change ranges of adjacent root mean square （RMS） of input signal, but not the difference between the power level of current signal and target signal. Software simulation and hardware implementing had been conducted with LTE frequency division dual （FDD） uplink signal and the results indicated that the proposed AGC algorithm can judge power status accurately and hence adjust the gain precisely in one step with a short delay, further, it can make full use of ADC digitalizing bit without oversaturation as well as keeping stable PAR. In addition, the mean error vector magnitude （EVM） was confined less than 1.6% to meet the 3rd generation partnership project （3GPP） standard well.

关键词： digitalizing bit stable PAR full-digital segmented AGC LTE FDD EVM

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Segmentation multi-dimensional crest factor reduction for multi-service supporting digital radio over fibre system

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The Journal of China Universities of Posts and Telecommunications 2018年第2期25卷 10-22页

作者： Wang Jie Tao Xiuli Hu Xiaoguang Guan enyi Ding Zhushun Li Wen School of Automation Science and Electrical Engineering Beihang University Beijing 100191 China Communication Technology Research Division Beijing Institute of Aerospace Control Devices Beijing 100039 China Fifth Technology Department Beijing Aerospace Times Optical-Electronic Technology Company Limited Beijing 100039 China

A segmentation multi-dimensional crest factor reduction （SMD-CFR） algorithm is proposed for multi-service supporting digital radio over fibre （DRoF） system. Benefit from segmentation dynamic clipping threshold and clipping factor got basing on characteristics of all service bands, the SMD-CFR is able to get better peak clipping and peak to average power ratio （PAPR） reduction for multi-band combined signal. Simulation results show that SMD-CFR gets more than 2.3 reduction in PAPR for two-bands combined signal of long term evolution （LTE） , which is much better than traditional one dimensional （1D）-CFR. Meanwhile, for 64-quadrature amplitude modulation （QAM） modulation and demodulation link, it has very small effect on bit error rate （BER） and error vector magnitude （EVM） , which are controlled less than 0. 1% and 0.2% respectively. For hardware experiment, SMD-CFR obtains 4.5% increase in drain efficiency and about 4 dBc increase in adjacent channel leakage ratio （ACLR）. These are very significant for the wide band power amplifier （PA） in multi-service supporting DRoF system.

关键词： CFR multi-dimensional dynamic crest factor DRoF muhi-service supporting LTE

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Environmental economic geography:Recent advances and innovative development

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Geography and Sustainability 2022年第2期3卷 152-163页

作者： Canfei He Shuqi He enyi Mu Jian Peng College of Urban and Environmental Sciences Peking UniversityBeijing 100871China Peking University-Lincoln Institute Center for Urban Development and Land Policy Beijing 100871China

Modern environmental problems are the result of human-environment interaction in the process of *** relationship between economic development and environmental quality is an important aspect of understanding human-environment interaction and has been widely concerned by multidisciplinary *** geography(EG)is a discipline that mainly focuses on the location and connections of economic *** has developed to environmental economic geography(EEG)by incorporating environmental factors into its research framework,considering the operational mechanism of the co-evolution of economy and environment,and the dynamic process of green transition of techno-economic *** the resource and environ-mental effects of R&D,production,trade,and other aspects of the economic cycle is beneficial to realizing the“greening”*** paper traces the background and theoretical development path of EEG and elaborates on the interaction between EEG and other research paradigms on environmental *** recent years,the focuses of EEG are as follows:(1)the“location-environment”relationship of production from the perspective of local actors;(2)the“GVC/GPN-environment”relationship of multinational enterprises and space of flows from the perspective of the global network;(3)the“trade/circulation-environment”relationship from the perspective of national linkages;and(4)the co-evolution of the economic system and environment from the perspective of synergistic evolution,with a focus on innovation and institutional *** future development trend of EEG is combined with the endogenous growth theory and the sustainable development theory,mainly from the aspects of endogenous,system integration and multi-scale,to explain the differences in environmental issues of differ-ent regional economic activities,and to promote the development of EEG theory and interdisciplinary research,strengthening the construction of global and regional sustai

关键词： Environmental economic geography Greening Evolution Sustainable development

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Current Research Trends and Perspectives on Solid-State Nanomaterials in Hydrogen Storage

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Research 2021年第1期2021卷 125-163页

作者： Jie Zheng Chen-Gang Wang Hui Zhou enyi Ye Jianwei Xu Zibiao Li Xian Jun Loh Institute of Materials Research and Engineering A^(∗)STAR(Agency for Science Technology and Research)2 Fusionopolis WayInnovis#08-03SingaporeSingapore 138634

Hydrogen energy,with environment amicable,renewable,efficiency,and cost-effective advantages,is the future mainstream substitution of fossil-based ***,the extremely low volumetric density gives rise to the main challenge in hydrogen storage,and therefore,exploring effective storage techniques is key hurdles that need to be crossed to accomplish the sustainable hydrogen *** physically or chemically stored into nanomaterials in the solid-state is a desirable prospect for effective large-scale hydrogen storage,which has exhibited great potentials for applications in both reversible onboard storage and regenerable off-board storage *** attractive points include safe,compact,light,reversibility,and efficiently produce sufficient pure hydrogen fuel under the mild *** review comprehensively gathers the state-of-art solid-state hydrogen storage technologies using nanostructured materials,involving nanoporous carbon materials,metal-organic frameworks,covalent organic frameworks,porous aromatic frameworks,nanoporous organic polymers,and nanoscale *** describes significant advances achieved so far,and main barriers need to be surmounted to approach practical applications,as well as offers a perspective for sustainable energy research.

关键词： mounted attractive substitution

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Effects of Two Potential Allelochemicals on the Photosystem II of Nitzschia closterium and Monostroma nitidum

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Phyton-International Journal of Experimental Botany 2023年第1期92卷 251-269页

作者： Bowen Huang enyi Xie Yu Ran Xinyi Chen Yongjian Huang Jianjun Cui Fishery College Guangdong Ocean UniversityZhanjiang524088China

In aquaculture,high-density seaweed farming brings higher economic benefits but also increases outbreaks of diatom *** effective control of diatom felt in high-density seaweed farming has always been a research *** study selected two potential allelochemicals 2-hydroxycinnamic acid and quinic acid to explore their effects on a diatom Nitzschia closterium and an economic seaweed Monostroma *** results showed that 2-hydroxycinnamic acid had better inhibitory effects than quinic acid on the growth,pigment content and photosynthetic efficiency of *** half-maximal inhibitory concentrations at 120 h(IC_(50–120 h))were 0.9000 and 1.278 mM,***,these allelochemicals had limited inhibitory effects on the growth,pigment content and photosynthetic efficiency of *** before 24 *** further explore the allelopathic effect of these chemicals,this study focused on the photosystem II energy fluxes of *** was found that 3 mM 2-hydroxycinnamic acid could destroy the whole photosynthetic system by devastating the PSII reaction centre(RC)before 24 h;however,the same concentration of quinic acid could only down-regulate the electron transport efficiency by changing the effective antenna size of an active RC and downregulating the PSII reaction centre *** experimental results are expected to provide a new strategy to control diatom felt blooms on the high-density seaweed farming areas.

关键词： Allelochemicals 2-hydroxycinnamic acid quinic acid Nitzschia closterium Monostroma nitidum photosynthetic system

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Superionic Conductivity in Ceria‑Based Heterostructure Composites for Low‑Temperature Solid Oxide Fuel Cells

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Nano-Micro Letters 2020年第12期12卷 264-283页

作者： Yifei Zhang Jingjing Liu Manish Singh enyi Hu Zheng Jiang Rizwan Raza Faze Wang Jun Wang Fan Yang Bin Zhu Jiangsu Provincial Key Laboratory of Solar Energy Science and Technology/Energy Storage Research Center School of Energy and EnvironmentSoutheast UniversityNanjing 210096People’s Republic of China Department of Chemistry Division for Pure and Applied BiochemistryLund UniversityNaturvetarvägen 1422362 LundSweden Clean Energy Research Lab(CERL) Department of PhysicsCOMSATS University IslamabadLahoreLahore 54000Pakistan

Ceria-based heterostructure composite(CHC)has become a new stream to develop advanced low-temperature(300–600°C)solid oxide fuel cells(LTSOFCs)with excellent power outputs at 1000 mW cm−2 *** state-ofthe-art ceria–carbonate or ceria–semiconductor heterostructure composites have made the CHC systems significantly contribute to both fundamental and applied science researches of LTSOFCs;however,a deep scientific understanding to achieve excellent fuel cell performance and high superionic conduction is still missing,which may hinder its wide application and *** review aims to establish a new fundamental strategy for superionic conduction of the CHC materials and relevant *** involves energy band and built-in-field assisting superionic conduction,highlighting coupling effect among the ionic transfer,band structure and alignment ***,theories of ceria–carbonate,e.g.,space charge and multi-ion conduction,as well as new scientific understanding are discussed and presented for functional CHC materials.

关键词： Ceria-based heterostructure composite Ceria–semiconductor Energy band Built-in field Solid oxide fuel cell

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