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Total phenolic content,in vitro antioxidant activity and chemical composition of plant extracts from semiarid Mexican region

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Asian Pacific Journal of Tropical Medicine 2015年第2期8卷 104-111页

作者： jorge e.wong-paz Juan C.Contreras-esquivel Raúl Rodríguez-Herrera María L.Carrillo-Inungaray Lluvia I.López Guadalupe V.Nevárez-Moorillón Cristóbal N.Aguilar Laboratory of Bioprocesses and Natural Products Food Research DepartmentSchool of ChemistryUniversidad Autónoma de CoahuilaSaltillo25280México Laboratory of Biochemistry Multidisciplinary Academic Unit-HuastecaUniversidad Autónoma de San Luis Potosí79060Cd.VallesS.L.P.Mexico Department of Microbiology School of ChemistryUniversidad Autónoma de Chihuahua31125 ChihuahuaMexico

Objective:To determine the extraction suitable conditions of total phenolic content(TPC) by heat-reflux system,antioxidant activities and HPLC characterization of the aqueous-ethanolic extracts of Jatropha dioica(J.dioica)(Dragon's blood).Flourensia cernua(F.cernua)(Tar bush).eucalyptus camaldulensis(e.camaldulensis)(eucalyptus) and Turnera diffusa(T.diffusa)(Damiana).Methods:TPC was evaluated by the well-known colorimetric assay using FolinCiocalteu reagent.The antioxidant activities were assayed by three methods based on scavenging of DPPH,ABTS and by lipid oxidation inhibition.The chemical composition of the extracts obtained was subject to HPLC analysis.Results:TPC in the plant extracts ranged from 2.3 to14.12 mg gallic acid equivalents/g for J.dioica and e.camaldulensis,respectively.The plant extracts of F.cernua,e.camaldulensis and T.diffusa showed similar strong antioxidant activities on scavenging of DPPH and lipid oxidation inhibition.In contrast,J.dioica extracts had lowest potential antioxidant in three assays used.HPLC assay showed the presence of several phenolic compounds in the extracts used.Conclusions:The results obtained suggest that F.cernua,e.camaldulensis and T.diffusa are potential sources to obtain bioactive phenolic compounds with high antioxidant properties which can be used in the factories as antioxidant agents or for treatments in diseases.

关键词： Plant-extracts Polyphenols Natural antioxidants Mexican plants Heat-reflux system

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Avian responses to an extreme weather event:The case of the‘Filomena’snowstorm in Madrid(central Spain)

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Avian Research 2024年第2期15卷 180-186页

作者： Carlos Lazaro Carlos Sanchez-García Fabian Casas e.jorge Tizado Department of Research Fundacion Artemisan13001 Ciudad RealSpain Department of Zoology Faculty of SciencesUniversity of GranadaGranadaSpain Department of Biodiversity and environmental Management Universidad de Leon24401 PonferradaSpain

Cold spells and severe weather may have detrimental effects in wild birds,but owing to the stochastic nature of these events,it is not always possible to measure their impacts.In January 2021,a strong snowstorm known as‘Filomena’affected Spain,mainly the region of Madrid(Central Spain),which was fully covered with snow and suffered freezing temperatures for a fortnight.Using bird surveys conducted in the winter-spring of 2020 and 2021(before and after Filomena)at same locations,we addressed the possible impact of the cold spell in three widespread gamebirds:Wood Pigeon(Columba palumbus),eurasian Magpie(Pica pica)and Red-legged Partridge(Alectoris rufa).No significant abundance differences were found between years for none of the species and hunting pressure was only significantly reduced for Partridges,hence this species may have been negatively affected by Filomena.Results suggest that in response to Filomena,Pigeons conducted partial migration in search of better conditions,while Magpies aggregated in certain areas of Madrid and Partridges endured the harsh conditions within their home ranges.Our results highlight the importance to alleviate negative impacts of extreme weather events in wild birds through management actions,especially for sedentary species.

关键词： Alectoris rufa Climate change Cold spell Columba palumbus Migration Pica pica Winter

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The electroweak monopole–antimonopole pair in the standard model

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Communications in Theoretical Physics 2024年第3期76卷 113-119页

作者： Dan Zhu Khai-Ming wong Guo-Quan wong School of Physics Universiti Sains Malaysia11800 USMPenangMalaysia

We present the first numerical solution that corresponds to a pair of Cho–Maison monopoles and antimonopoles(MAPs) in the SU(2) × U(1) Weinberg–Salam(WS) theory.The monopoles are finitely separated,while each pole carries a magnetic charge ±4π/e.The positive pole is situated in the upper hemisphere,whereas the negative pole is in the lower hemisphere.The Cho–Maison MAP is investigated for a range of Weinberg angles,0.4675≤ tan θ_(W)≤10,and Higgs self-coupling,0 ≤ β ≤ 1.7704.The magnetic dipole moment(μm) and pole separation(d_(z)) of the numerical solutions are calculated and analyzed.The total energy of the system,however,is infinite due to point singularities at the locations of monopoles.

关键词： magnetic monopole Cho-Maison monopole Weinberg-Salam model

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Functionalized selenium nanoparticles ameliorated acetaminophen-induced hepatotoxicity through synergistically triggering PKCδ/Nrf2 signaling pathway and inhibiting CYP 2e1

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Food Science and Human Wellness 2024年第2期13卷 932-945页

作者： Si Zou Yetao Gong Xiujie Li Yanbin Wu Jinzhong Wu Jianguo Wu Ka-Hing wong College of Pharmacy Fujian University of Traditional Chinese MedicineFuzhou 350122China Research Institute for Future Food The Hong Kong Polytechnic UniversityHong Kong 999077China Department of Food Science and Nutrition The Hong Kong Polytechnic UniversityHong Kong 999077China

Selenium nanoparticles(SeNPs)have been demonstrated potential for use in diseases associated with oxidative stress.Functionalized SeNPs with lower toxicity and higher biocompatibility could bring better therapeutic activity and clinical application value.Herein,this work was conducted to investigate the protective effect of Pleurotus tuber-regium polysaccharide-protein complex funtionnalized SeNPs(PTR-SeNPs)against acetaminophen(APAP)-induced oxidative injure in HepG2 cells and C57BL/6J mouse liver.Further elucidation of the underlying molecular mechanism,in particular their modulation of Nrf2 signaling pathway was also performed.The results showed that PTR-SeNPs could significantly ameliorate APAP-induced oxidative injury as evidenced by a range of biochemical analysis,histopathological examination and immunoblotting study.PTR-SeNPs could hosphorylate and activate PKCδ,depress Keap1,and increase nuclear accumulation of Nrf2,resulting in upregulation of GCLC,GCLM,HO-1 and NQO-1 expression.Besides,PTR-SeNPs suppressed the biotransformation of APAP to generate intracellular ROS through CYP 2e1 inhibition,restoring the mitochondrial morphology.Furthermore,the protective effect of PTR-SeNPs against APAP induced hepatotoxicity was weakened as Nrf2 was depleted in vivo,indicating the pivotal role of Nrf2 signaling pathway in PTR-SeNPs mediated hepatoprotective efficacy.Being a potential hepatic protectant,PTR-SeNPs could serve as a new source of selenium supplement for health-promoting and biomedical applications.

关键词： PTR-SeNPs(polysaccharide-proteincomplex functionalized selenium nanoparticles) Acetaminophen-induced hepatotoxicity Nuclear factor erythroid 2-related factor 2 Cytochrome P450 enzyme 2e1 Mitochondria

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Review of Networked Microgrid Protection:Architectures,Challenges,Solutions,and Future Trends

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CSee Journal of Power and energy Systems 2024年第2期10卷 448-467页

作者： jorge de la Cruz Ying Wu John e.Candelo-Becerra Juan C.Vasquez Josep M.Guerrero Center for Research on Microgrids(CROM) Department of Energy TechnologyAalborg University9220 AalborgDenmark Facultad de Minas Departamento de Energia Eléctrica y AutomaticaUniversidad Nacional de ColombiaSede MedellinCarrera 80 No.65-223RobledoMedellin 050041Colombia. Center for Research on Microgrids at UPC(UPC CROM) Department of Electronic EngineeringTechnical University of Catalonia(UPC)08019 Barcelona Spain ICReA Pg.Lluis Companys 2308010 BarcelonaSpain Center for Research on Microgrids at AAU(AAU CROM) AAU EnergyAalborg University(AAU)9220 Aalborg EastDenmark

Design and selection of advanced protection schemes have become essential for reliable and secure operation of networked microgrids.Various protection schemes that allow correct operation of microgrids have been proposed for individual systems in different topologies and connections.Nevertheless,protection schemes for networked microgrids are still in devel-opment,and further research is required to design and operate advanced protection in interconnected systems.Interconnection of these microgrids in different nodes with various intercon-nection technologies increases fault occurrence and complicates protection operation.This paper aims to point out challenges in developing protection for networked microgrids,potential solutions,and research areas that need to be addressed for their development.First,this article presents a systematic analysis of different microgrid clusters proposed since 2016,including several architectures of networked microgrids,operation modes,components,and utilization of renewable sources,which have not been widely explored in previous review papers.Second,the paper presents a discussion on protection systems currently available for microgrid clusters,current challenges,and solutions that have been proposed for these systems.Finally,it discusses the trend of protection schemes in networked microgrids and presents some conclusions related to implementation.IndexTerms—Adaptive eprotection,microgrid cluster,microgrid,multiple microgrid,networked microgrid,real-time simulation,smart grid.

关键词： Adaptive eprotection microgrid cluster microgrid multiple microgrid networked microgrid real-time simulation smart grid

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Incorporating physiological knowledge into correlative species distribution models minimizes bias introduced by the choice of calibration area

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Marine Life Science & Technology 2024年第2期6卷 349-362页

作者： Zhixin Zhang Jinxin Zhou jorge García Molinos Stefano Mammola Ákos Bede‑Fazekas Xiao Feng Daisuke Kitazawa jorge Assis Tianlong Qiu Qiang Lin CAS Key Laboratory of Tropical Marine Bio-resources and ecology South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China Guangdong Provincial Key Laboratory of Applied Marine Biology South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China Marine Biodiversity and ecological evolution Research Center South China Sea Institute of OceanologyGuangzhou 510301China Global Ocean and Climate Research Center South China Sea Institute of OceanologyGuangzhou 510301China Institute of Industrial Science The University of Tokyo5-1-5 KashiwanohaKashiwaChiba 277-8574Japan Arctic Research Center Hokkaido UniversitySapporoHokkaido 001-0021Japan Finnish Museum of Natural History University of HelsinkiHelsinkiFinland Molecular ecology Group(MeG) Water Research Institute(IRSA)National Research Council of Italy(CNR)28922 Verbania PallanzaItaly National Biodiversity Future Center(NBFC) PalermoItaly Institute of ecology and Botany HUN-REN Centre for Ecological ResearchVácrátótHungary Department of environmental and Landscape Geography ELTE Eötvös Loránd UniversityBudapestHungary Department of Biology University of North CarolinaChapel HillNC 27599USA Centre of Marine Sciences University of AlgarveCampus de GambelasFaroPortugal CAS Key Laboratory of experimental Marine Biology Institute of OceanologyChinese Academy of SciencesQingdao 266071China University of Chinese Academy of Sciences Beijing 100049China

Correlative species distribution models(SDMs)are important tools to estimate species’geographic distribution across space and time,but their reliability heavily relies on the availability and quality of occurrence data.estimations can be biased when occurrences do not fully represent the environmental requirement of a species.We tested to what extent species’physiological knowledge might influence SDM estimations.Focusing on the Japanese sea cucumber Apostichopus japonicus within the coastal ocean of east Asia,we compiled a comprehensive dataset of occurrence records.We then explored the importance of incorporating physiological knowledge into SDMs by calibrating two types of correlative SDMs:a naïve model that solely depends on environmental correlates,and a physiologically informed model that further incorporates physiological information as priors.We further tested the models’sensitivity to calibration area choices by fitting them with different buffered areas around known presences.Compared with naïve models,the physiologically informed models successfully captured the negative influence of high temperature on A.japonicus and were less sensitive to the choice of calibration area.The naïve models resulted in more optimistic prediction of the changes of potential distributions under climate change(i.e.,larger range expansion and less contraction)than the physiologically informed models.Our findings highlight benefits from incorporating physiological information into correlative SDMs,namely mitigating the uncertainties associated with the choice of calibration area.Given these promising features,we encourage future SDM studies to consider species physi-ological information where available.

关键词： Bayesian approach Climate change Habitat suitability Physiological knowledge Species distribution model

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Tribological behavior of lubricant-impregnated porous polyimide

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Friction 2024年第4期12卷 711-725页

作者： Jinbang LI Ningning ZHOU Janet S.S.wong School of Mechanical engineering and Mechanics Ningbo UniversityNingbo 315211China Beijing Key Laboratory of Long-life Technology of Precise Rotation and Transmission Mechanisms Beijing Institute of Control EngineeringBeijing 100029China Department of Mechanical engineering Imperial College LondonLondon SW72AZUK

Porous materials impregnated with lubricants can be used in conditions where limited lubricant is desirable.In this work,three porous polyimides(PPI)with different densities were prepared.Polyalphaolefin(PAO)impregnated PPI(iPPI)discs were rubbed against steel and sapphire balls.In operando observations of the iPPI-sapphire contacts show that oil is released under an applied load,forming a meniscus around contacts.Cavitation at the outlet is created at high sliding speeds.The amount of released oil increases with increasing PPI porosity.Contact moduli,e*,estimated based on the actual contact size show that trapped oil in iPPIs contributes to load support.At higher speeds,tribological rehydration of the contact occurs in low density iPPI,with that e*rises with speed.For high density PPIs,high speeds give a constantly high e*which is limited by the viscoelastic properties of the PPI network and possibly the rate of oil exudation.Friction of iPPI-steel contacts is governed by the mechanical properties of the PPI,the flow of the lubricant,and the roughness of the PPI surfaces.For low-and medium-density(highly porous,high roughness)PPIs,large amount of oil is released,and lubrication is mainly via lubricant restricted in the contact in the pores and possibly tribological rehydration.For high density(low porosity)PPI,with lower roughness,hydrodynamic lubrication is achieved which gives the lowest friction.Our results show that polymeric porous materials for effective lubrication require the optimization of its surface roughness,stiffness,oil flow,and oil retentions.

关键词： polyimide porous material friction mechanism polymer limited lubrication

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Transfer of Highest Weight Modules and Small Unipotent Representations

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Acta Mathematica Sinica,english Series 2024年第3期40卷 772-791页

作者： Hai An He Jing Song HUANG Kayue Daniel wong Department of Mathematics College of SciencesShanghai UniversityShanghai 200444P.R.China Newtouch Center for Mathematics of Shanghai University Shanghai 200444P.R.China Mathematics Research Center School of Science and EngineeringThe Chinese University of Hong KongShenzhen 518172P.R.China

We study the transfer between small special unipotent representations for all equal rank real forms of type e_(6) and e_(7). As a consequence, one can verify these modules are unitarity using the results of Wallach an... 详细信息

关键词： Unipotent representations Wallach representations Transfer of unitary modules

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Assessing parameter sensitivity in a university campus COVID-19 model with vaccinations

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Infectious Disease Modelling 2023年第2期8卷 374-389页

作者： Meghan Rowan Childs Tony e.wong Rochester Institute of Technology 1 Lomb Memorial DrRochesterNY14623USA

From the beginning of the COVID-19 pandemic,universities have experienced unique challenges due to their dual nature as a place of education and residence.Current research has explored non-pharmaceutical approaches to combating COVID-19,including representing in models different categories such as age groups.One key area not currently well represented in models is the effect of pharmaceutical preventative measures,specifically vaccinations,on COVID-19 spread on college campuses.There remain key questions on the sensitivity of COVID-19 infection rates on college campuses to potentially time-varying vaccine immunity.Here we introduce a compartment model that decomposes a campus population into constituent subpopulations and implements vaccinations with timevarying efficacy.We use this model to represent a campus population with both vaccinated and unvaccinated individuals,and we analyze this model using two metrics of interest:maximum isolation population and symptomatic infection.We demonstrate a decrease in symptomatic infections occurs for vaccinated individuals when the frequency of testing for unvaccinated individuals is increased.We find that the number of symptomatic infections is insensitive to the frequency of testing of the unvaccinated subpopulation once about 80%or more of the population is vaccinated.Through a Sobol’global sensitivity analysis,we characterize the sensitivity of modeled infection rates to these uncertain parameters.We find that in order to manage symptomatic infections and the maximum isolation population campuses must minimize contact between infected and uninfected individuals,promote high vaccine protection at the beginning of the semester,and minimize the number of individuals developing symptoms.

关键词： COVID-19 Vaccination Subpopulation Modeling Sensitivity analysis University

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Insights on advanced substrates for controllable fabrication of photoanodes toward efficient and stable photoelectrochemical water splitting

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Carbon energy 2024年第4期6卷 164-221页

作者： Huilin Hou Gang Shao Yang Wang Wai‐Yeung wong Weiyou Yang Institute of Micro/Nano Materials and Devices Ningbo University of TechnologyNingboChina School of Materials Science and engineering Zhengzhou UniversityZhengzhouChina Department of Applied Biology and Chemical Technology and Research Institute for Smart energy The Hong Kong Polytechnic UniversityHong KongChina

Conversion of solar energy into H2 by photoelectrochemical(PeC)water splitting is recognized as an ideal way to address the growing energy crisis and environmental issues.In a typical PeC cell,the construction of photoanodes is crucial to guarantee the high efficiency and stability of PeC reactions,which fundamentally rely on rationally designed semiconductors(as the active materials)and substrates(as the current collectors).In this review work,we start with a brief introduction of the roles of substrates in the PeC process.Then,we provide a systematic overview of representative strategies for the controlled fabrication of photoanodes on rationally designed substrates,including conductive glass,metal,sapphire,silicon,silicon carbide,and flexible substrates.Finally,some prospects concerning the challenges and research directions in this area are proposed.

关键词： hydrogen photoanode photoelectrochemical substrates water splitting

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