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Phytochemical analysis and anti-oxidant activities of Albuca bracteata *** Albuca setosa Jacq bulb extracts used for the management of diabetes in the Eastern Cape,South Africa

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Asian Pacific Journal of Tropical Biomedicine 2017年第6期7卷 577-584页

作者： samuel Odeyemi Anthony Afolayan Graeme Bradley Department of Biochemistry and Microbiology University of Fort Hare MPED Research Niche Area Department of BotanyUniversity of Fort Hare

Objective:The bulb of Albuca bracteata Jacq.,and Albuca setosa commonly used in Eastern Cape Province of South Africa for the treatment of several types of disease conditions including diabetes,was investigated for their phytochemical contents and antioxidant ***:The antioxidant activity was determined by evaluating the effect of various solvent extracts(acetone,methanol,ethanol and water) on 2,2 – diphenyl-2-picrylhydrazyl(DPPH) scavenging activity,2,20– azino-bis(3-ethylbenzthiazoline-6-sulfonic acid diammonium salt(ABTS),ferric reducing power,hydrogen peroxide and nitric oxide scavenging activity while the various extracts were also analysed for phytochemical their ***:The results obtained indicate that polyphenols,proanthocyanidins,saponins and alkaloids are present in higher *** composition of phenols(117 mg/g),flavonols(26.28 mg/g),proanthocyanidins(84.85 mg/g) and flavonoids(5.36 mg/g) were significantly higher in the acetone extract while saponin and alkaloids contents were higher in the aqueous *** studies of the extracts for nitric oxide,hydrogen peroxide,ABTS and DPPH showed high antioxidant potential in a concentration-dependent manner that was not significantly different from Vitamin C,BHT and Rutin used as standard *** methanol extract showed higher ferric reducing potential compared to the aqueous extract but was significantly different from Vitamin C,BHT and ***:This implies that the bulb of Albuca bracteata may serve as a natural source of antioxidants,which together with the numerous phytochemicals present,could account for its folkloric use as a medicinal plant.

关键词： Phytochemicals Antioxidants Ornitogalum longibrateum Albuca bracteata Diabetes Albuca setosa

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AnAll-Regime Lagrange-Projection Like Scheme for the Gas Dynamics Equations on Unstructured Meshes

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Communications in Computational Physics 2016年第6期20卷 188-233页

作者： Christophe Chalons Mathieu Girardin samuel Kokh LMV-UMR 8100 Univ.Versailles Saint-Quentin-en-YvelinesUFR des SciencesBatiment Fermat45 avenue des Etats-Unis78035 Versailles cedexFrance DEN/DANS/DM2S/STMF/LMEC CEA Saclay bat.454 PC 4791191 Gif sur Yvette CedexFrance LRC MANON Laboratoire de Recherche Conventionne CEA/DEN/DANS/DM2S and UPMC-CNRS/LJLL Maison de la Simulation USR 3441 Digiteo Labsbat.565PC 190CEA Saclay91191 Gif-sur-YvetteFrance DEN/DANS/DM2S/STMF CEA Saclay91191 Gif-sur-YvetteFrance

We propose an all regime Lagrange-Projection like numerical scheme for the gas dynamics *** all regime,we mean that the numerical scheme is able to compute accurate approximate solutions with an under-resolved discretization with respect to the Mach number M,*** that the ratio between the Mach number M and the mesh size or the time step is small with respect to *** key idea is to decouple acoustic and transport phenomenon and then alter the numerical flux in the acoustic approximation to obtain a uniform truncation error in term of *** modified scheme is conservative and endowed with good stability properties with respect to the positivity of the density and the internal energy.A discrete entropy inequality under a condition on the modification is obtained thanks to a reinterpretation of the modified scheme in the Harten Lax and van Leer formalism.A natural extension to multi-dimensional problems discretized over unstructured mesh is *** a simple and efficient semi implicit scheme is also *** resulting scheme is stable under a CFL condition driven by the(slow)material waves and not by the(fast)acoustic waves and so verifies the all regime *** evidences are proposed and show the ability of the scheme to deal with tests where the flow regime may vary from low to high Mach values.

关键词： Gas dynamics equations low-Mach regime finite volume schemes all-regime schemes Lagrange-Projection like schemes large time-steps

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Strategies for reducing the costs of clean-energy technologies in buildings in Nigeria

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Clean Energy 2020年第4期4卷 349-359页

作者： samuel Ekung Victor Ohama Reginald Ajiero Department of Quantity Surveying Imo State UniversityOwerriNigeria Department of Building University of UyoUyoNigeria

The costs of clean-energy technologies are currently very high and their adoption in buildings is *** study evaluated strategies for improving the cost performance of photovoltaic(PV)electricity applied in buildings in Nigeria using a questionnaire survey involving 415 *** efficacy of each strategy and consensus in respondents’perceptions were determined using Fuzzy Set Theory and Kruskal-Wallis *** top four strategies for achieving PV-cost reduction are mandating green buildings,standardization of building designs and PV components,facilitating import licensing and massive public *** these strategies to improve the PV value chain will increase the supply capacity of clean energy in emerging markets.

关键词： buildings cost reduction photovoltaic sustainable energy sustainable development

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Coupling between fluids and rock deformation in the continental crust:Preface

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Geoscience Frontiers 2019年第6期10卷 2085-2092页

作者： Silvia Japas Sebastian Oriolo Vinod samuel Instituto de Geociencias Básicas Aplicadas y Ambientales(IGeBA)CONICETUniversidad de Buenos AiresCiudad UniversitariaBuenos AiresArgentina Department of Earth System Sciences Yonsei UniversitySeoulRepublic of Korea

*** Fluids are essential and widespread components of the Earth *** regulate the main process of mass and energy transport,conditioning the geochemical and geophysical evolution of the crust(Bredehoeft and Norton.1990)and,consequently,its properties and mechanical *** coupling between fluids,rock deformation,and heat are crucial engines for plate tectonics,playing a leading role in the rheology and evolution of the lithosphere(*** et al.,2000;Kennedy and van Soest,2007;Thompson,2010;Miller.2013;Yardley and Bodnar,2014:Hirauchi et al.,2016:Menzies et al.,2016;Plümper et al.,2017;Vizán et al.,2017).

关键词： rock crust continental

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Presbyopic correction on the cornea

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Eye and Vision 2014年第1期1卷 24-33页

作者： samuel Arba Mosquera Jorge L Alió SCHWIND eye-tech-solutions KleinostheimGermany Vissum Corporation AlicanteSpain Division of Ophthalmology Universidad Miguel HernándezAlicanteSpain.

Purpose:The aim of this systematic review was to synthesize and appraise the evidence of the benefits of presbyopic correction on the cornea for visual ***:Comprehensive search was conducted in MEDLINE using keywords like“presbylasik”,“presbyopic refractive surgery”,“corneal pseudoaccommodation”and“corneal multifocality”.We reviewed corrected and uncorrected visual acuities for distance and near(uncorrected distance visual acuity(UDVA),uncorrected near visual acuity(UNVA),corrected distance visual acuity(CDVA),distance corrected near visual acuity(DCNVA),corrected near visual acuity(CNVA)),along with the refractive outcomes in spherical equivalent(SE)and astigmatism comparing the differences observed between preoperative myopic and hyperopic patients,as well as among ***-one studies met the inclusion and quality *** provides excellent distance and near uncorrected acuities,but with a 17%retreatment and a 5%reversal *** multifocal ablations result in 12%loss of 2 or more lines of CDVA,and a 21%retreatment *** Blended Vision provides excellent UDVA,but with a 19%retreatment *** experiences with Supracor show moderate predictability and a 22%retreatment *** results in 9%loss of 2 or more lines of *** provides excellent UDVA,with only a 1%retreatment rate,but a 6%reversal *** experiences with PresbyMAX provided excellent UNVA and DCNVA,showing excellent predictability and a 1%reversal ***:The findings have implications for clinicians and policymakers in the health-care industry and emphasize the need for additional trials examining this important and widely performed clinical procedure.

关键词： Presbyopic refractive correction Presbylasik Corneal pseudoaccommodation Corneal multifocality Distance corrected near visual acuity Monovision Laser Blended Vision Supracor and Intracor KAMRA PresbyMAX

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Inaccuracies in the history of a well-known introduction:a case study of the Australian House Sparrow(Passer domesticus)

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Chinese Birds 2016年第2期7卷 95-109页

作者： samuel C.Andrew Simon C.Griffith Department of Biological Sciences Macquarie University

Background:Modern ecosystems contain many invasive species as a result of the activity of acclimatisation societies that operated in the second half of the nineteenth century,and these species provide good opportunities for studying invasion ***,to gain insight into the ecological and genetic mechanisms that determine the rate of colonization and adaptation to new environments,we need a good understanding of the history of the introduced species,and a knowledge of the source population,timing,and number of individuals introduced is particularly ***,any inaccuracies in the history of an introduction will affect subsequent assumptions and ***:Focusing on a single well-known species,the House Sparrow(Passer domesticus),we have documented the introduction into Australia using primary sources(*** records and newspaper articles).Results:Our revised history differs in a number of significant ways from previous *** evidence indicates that the House Sparrow was not solely introduced from source populations in England but also from Germany and most strikingly also from India—with the latter birds belonging to a different *** also clarify the distinction between the number released and the number of founders,due to pre-release captive breeding programs,as well as identifying inaccuracies in a couple of well-cited sources with respect to the range expansion of the introduced ***:Our work suggests that caution is required for those studying introductions using the key sources of historical information and ideally should review original sources of information to verify the accuracy of published accounts.

关键词： Acclimatisation Bottlenecks Propagule size Range expansion Hybridisation

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Flying Capacitor Design Considerations for a 48-to-12 V,35 A Split-phase Dickson SC Converter

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Chinese Journal of Electrical Engineering 2020年第4期6卷 28-41页

作者： Richard(Yue) Sun samuel Webb Yan-Fei Liu Department of Electrical and Computer Engineering Queen's UniversityKingston K7L 3N6Canada

Switched-capacitor converters can deliver better performance,power density,and switch utilization compared to inductor-based power converters,but they suffer from current spikes during switching due to capacitor charge *** can be solved by methods such as split-phase control,which was developed to address charge redistribution in Dickson SC converters by controlling the charging and discharging of the circuit‟s flying capacitors,such that the equivalent branch voltages line up when the circuit switches ***,split-phase control is most effective at compensating for charge redistribution when all the circuit‟s flying capacitors are matched in capacitance *** between the capacitance values of the circuit flying capacitors may result in split-phase control not being able to fully compensate for charge redistribution,due to the different charge/discharge rates of the flying *** work presented in this paper provides an in-depth analysis of the sensitivity of the split-phase Dickson converter to mismatches in flying capacitor values,as well as discussions regarding the design considerations and prototype test results of a split-phase Dickson converter for high-current loads.

关键词： Switched-capacitor converter Dickson converter split-phase control capacitor mismatch

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Phages and their potential to modulate the microbiome and immunity

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Cellular & Molecular Immunology 2021年第4期18卷 889-904页

作者： Sara Federici samuel P.Nobs Eran Elinav Immunology Department Weizmann Institute of ScienceRehovot 7610001Israel Cancer-Microbiome Division Deutsches Krebsforschungszentrum(DKFZ) Neuenheimer Feld 28069120 HeidelbergGermany

Bacteriophages(hence termed phages)are viruses that target bacteria and have long been considered as potential future treatments against antibiotic-resistant bacterial ***,the molecular nature of phage interactions with bacteria and the human host has remained elusive for decades,limiting their therapeutic *** many phages and their functional repertoires remain unknown,the advent of next-generation sequencing has increasingly enabled researchers to decode new lytic and lysogenic mechanisms by which they attack and destroy ***,the last decade has witnessed a renewed interest in the utilization of phages as therapeutic vectors and as a means of targeting pathogenic or commensal bacteria or inducing ***,the narrow host range,immense antibacterial repertoire,and ease of manipulating phages may potentially allow for their use as targeted modulators of pathogenic,commensal and pathobiont members of the microbiome,thereby impacting mammalian physiology and immunity along mucosal surfaces in health and in microbiomeassociated *** this review,we aim to highlight recent advances in phage biology and how a mechanistic understanding of phage-bacteria-host interactions may facilitate the development of novel phage-based *** provide an overview of the challenges of the therapeutic use of phages and how these could be addressed for future use of phages as specific modulators of the human microbiome in a variety of infectious and noncommunicable human diseases.

关键词： Microbiota Microbiome Phages

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Risk of predation: a critical force driving habitat quality perception and foraging behavior of granivorous birds in a Nigerian forest reserve

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Avian Research 2019年第3期10卷 285-293页

作者： Umarfarooq A.Abdulwahab samuel Temidayo Osinubi Jacinta Abalaka A.P.Leventis Ornithological Research Institute University of JosJosPlateau StateNigeria Department of Watershed Sciences and the Ecology Center Utah State UniversityLoganUT 84322-5210USA FitzPatrick Institute of African Ornithology University of Cape TownRondeboschCape TownSouth Africa

Background:Understanding the factors that influence the foraging behavior and perception of habitat quality by animals has long been the focus in ecology. Due to the direct effect resource acquisition has on an individual's fitness and species' survival, predation risk is considered widely to be a major driver of foraging decision. The objectives of this study were to investigate how predation risk is perceived by granivorous bird species with respect to different habitat and microhabitat types, time of day and food types in Amurum Forest Reserve, Nigeria, with a view to direct future conservation planning. Methods: For 3 months, we conducted field experiments to measure giving-up densities (GUD, the amount of food left behind in artificial patches after birds cease to forage in it) and how it differs with habitat types, microhabitats, times of day, and food types. General linear mixed-effect models (GLMMs) were fitted to investigate the differences in GUD with respect to the aforementioned variables. Model selection was done based on the Akaike's Information Criterion (AIC). Results: There was no significant difference in GUDs across habitats. However, there was a significant difference in GUDs between microhabitats. Higher food remnants were recorded in the open than in cover microhabitats, as birds exploited food patches in the cover more. Time of day influenced foraging behavior in the birds. They foraged more in the morning than afternoon across all three habitats except for the gallery forest where birds foraged less in the morning. Higher GUDs were recorded in open than cover microhabitats both in the morning and the afternoon. Birds had a preference for rice, millet, and groundnut respectively. Conclusion:The differences in GUDs were very indicative of differences in foraging behavior and perception of resource availability in response to perceived predation risk. Therefore, this study suggests that the understanding of foraging decisions can be a veritable

关键词： Food availability Foraging behavior Giving-up density Habitat quality Predation risk

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Climate Change Effects on Employment in the Nigeria's Agricultural Sector

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Chinese Journal of Urban and Environmental Studies 2023年第3期11卷 149-171页

作者： Kehinde samuel ALEHILE Department of Economics Faculty of Social Sciences Kogi State University

Climate change poses mounting risks to agricultural development and rural livelihoods in *** study investigates the impacts of climate change on agricultural sector employment in Nigeria. Agriculture provides income and sustenance for much of Nigeria’s rural ***, smallholder rain-fed farming predominates, with minimal resilience to climate *** data reveal rising temperatures and declining, erratic rainfall across Nigeria’s agroecological zones since the 1970s. Crop modeling predicts further climate changes will reduce yields of key staple crops. This threatens the viability of smallholder agriculture and risks widespread job losses. The study adopts a nonlinear autoregressive distributed lag(NARDL)modeling approach to evaluate climate change effects on agricultural sector employment in Nigeria from 1990 to 2020. Findings reveal reduced rainfall initially raises employment, as farming requires more labor in dry conditions. However, protracted droughts significantly reduce agricultural jobs. Increased temperatures consistently lower farm employment through reduced yields and incomes. Based on these findings, the study recommends that adaptive strategies are urgently needed to build resilience, promote climate-smart agriculture, and safeguard rural livelihoods.

关键词： Climate change agricultural employment rainfall temperature Nigeria

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