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Antioxidant and antimutagenic activities of bark extract of Terminalia arjuna

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Asian Pacific Journal of Tropical Medicine 2010年第12期3卷 965-970页

作者： Gollapalle Lakshminarayana shastry Viswanatha Santosh Kumar Vaidya Ramesh c Nandakumar Krishnadas Srinath Rangappa Department of Pharmacology PES College of PharmacyBangalore-560050 India Department of Pharmacology St.John's College of PharmacyBangalore-560040 India Department of Pharmacology Manipal College of Pharmaceutical SciencesManipal-576104 India

Objective:The alcoholic extract of stem bark of Terminalia arjuna（ALTA） was screened for antioxidant and antimutagenic（anticlastogenic） ***:Antioxidant property was determined by l,l,Diphynyl,2-Picryl hydrazyl（DPPH） assay,super oxide radical scavenging activity,lipid peroxidation assay and total polyphenolic content was determined by Folin-ciocalteau’s *** activity was evaluated using micronucleus test in mice. Results:The ALTA has shown potent antioxidant activity with Ec50 of 2.491±0.160,50.110±0.150 & 71.000±0.250 in DPPH assay,superoxide radical scavenging activity and lipid peroxidation assay, which is comparable with ascorbic acid with Ec50 of 2.471±0.140,40.500±0.390 and 63.000±0.360 *** micronucleus test,ALTA（100 & 200 mg/kg,p.o.） showed significant reduction in percentage of micronucleus in both polychromatic erythrocytes（PcE） and normochromatie erythrocytes（NcE） and also shown significant reduction in P/N ***:These results suggested that ALTA possess significant antioxidant and antimutagenic activity.

关键词： Terminalia arjuna Antioxidant activity Antimutagenic activity Micronuclease test

Genetic Diversity of crop Wild Relatives under Threat in Yangtze River Basin:call for Enhanced In Situ conservation and Utilization

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Molecular Plant 2019年第12期12卷 1535-1538页

作者： Qin L i Yao Zhao Xiaoguo Xiang Jiakuan c hen Jun Rong Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering Institute of Biodiversity ScienceFudan UniversityShanghai 200438China Jiangxi Province Key Laboratory of Watershed Ecosystem change and Biodiversity Center for Watershed EcologyInstitute of Life Science and School of Life SciencesNanchang UniversityNanchang 330031China

The changing climate threatens agricultural production and food security(Vincent et al.,2019).The limited genetic diversity of crops restricts the improvement potential,which acts as an inevitable barrier for breeding... 详细信息

关键词： breeding crops cultivated

Structures and formation mechanisms of dislocation-induced precipitates in relation to the age-hardening responses of Al-Mg-Si alloys

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Journal of Materials Science & Technology 2020年第6期41卷 127-138页

作者： Y.X.Lai W.Fan M.J.Yin c.L.Wu J.H.chen center for High-Resolution Electron Microscopy College of Materials Science&EngineeringHunan UniversityChangsha 410082China Electron Microscopy center Shenzhen UniversityShenzhen 518060China

In the slightly deformed Al-Mg-Si alloys,dislocation-induced precipitates are frequently observed,and they usually line up,forming sophisticated precipitation *** atomic-resolution electron microscopy in association with hardness measurements,we systematically investigated these precipitates in relation to the age-hardening responses of the *** study reveals that the majority of dislocation-induced complex precipitates are actually short-range ordered while long-range disordered polycrystalline precipitates and multiphase composite precipitates,including polycrystalline U2 precipitates,B’/U2,B’-2/U2,B’/B’-2/U2 and’/U2 composite *** is suggested that the formation of these complex precipitates is mainly owing to a high nucleation rate and rapid growth of different precipitate phases parallel to the associated dislocation *** dislocation-induced precipitates consume more Mg than Si from the matrix and have a high formation kinetics,they will have different impacts on the matrix precipitation in different types of Al-Mg-Si *** results further demonstrate that for the"normally-β"-hardened"alloy,their formation leads to a coarser precipitate microstructure in the matrix,whereas for the"normally-β’-hardened"alloy,their formation reverses the precipitation pathway in the matrix,resulting in a reduced age-hardening potential of the former alloy and an improved age-hardening potential of the latter alloy.

关键词： Al-Mg-Si alloys Precipitation Dislocation Age-hardening Electron microscopy

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Isotropic Affine Spheres

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Acta Mathematica Sinica,English Series 2012年第10期28卷 1955-1972页

作者： Olivier BIREMBAUX Mirjana DJORI Université Lille Nord de France F-59000 Lille Laboratoire de Mathématiques et ses Applications de Valenciennes Université de Valenciennes et du Hainaut Cambrésis Faculty of Mathematics University of Belgrade Studentski trg 16

In this paper, we study affine spheres which are isotropic and we obtain a complete clas- sification. In particular, we show that all such afline spheres are hyperbolic afiine spheres, isometric with SL（3, R）/SO（3... 详细信息

关键词： Afline sphere isotropic submanifold symmetric space

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Speciation with gene flow via cycles of isolation and migration:insights from multiple mangrove taxa

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National Science Review 2019年第2期6卷 275-288页

作者： Ziwen He Xinnian Li Ming Yang Xinfeng Wang cairong Zhong Norman c.Duke chung-I Wu Suhua Shi State Key Laboratory of Biocontrol Guangdong Key Lab of Plant Resources Key Laboratory of Biodiversity Dynamics and Conservation of Guangdong Higher Education InstitutesSchool of Life Sciences Sun Yat-Sen University Department of Ecology and Evolution University of Chicago cAS Key Laboratory of Genome Sciences and Information Beijing Institute of GenomicsChinese Academy of Sciences Hainan Dongzhai Harbor National Nature Reserve Administration centre for Tropical Water and Aquatic Ecosystem Research James Cook University

Allopatric speciation requiring an unbroken period of geographical isolation has been the standard model of neo-Darwinism. While doubts have been repeatedly raised, strict allopatry without any gene flow remains a plausible mechanism in most cases. To rigorously reject strict allopatry, genomic sequences superimposed on the geological records of a well-delineated geographical barrier are necessary. The Strait of Malacca,narrowly connecting the Pacific and Indian Ocean coasts, serves at different times either as a geographical barrier or a conduit of gene flow for coastal/marine species. We surveyed 1700 plants from 29 populations of 5 common mangrove species by large-scale DNA sequencing and added several whole-genome assemblies. Speciation between the two oceans is driven by cycles of isolation and gene flow due to the fluctuations in sea level leading to the opening/closing of the Strait to ocean currents. Because the time required for speciation in mangroves is longer than the isolation phases, speciation in these mangroves has proceeded through many cycles of mixing-isolation-mixing, or MIM, cycles. The MIM mechanism, by relaxing the condition of no gene flow, can promote speciation in many more geographical features than strict allopatry can. Finally, the MIM mechanism of speciation is also efficient, potentially yielding mn(m > 1) species after n cycles.

关键词： speciation gene flow allopatry geographical isolation mangrove

commentary on “Prevalence and evolution of drug resistance HIV-1 vari-ants in Henan, china”

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cell Research 2005年第Z1期15卷 850-851页

作者： Bruce L GILLIAM Robert R REDFIELD Richard Y ZHAO Robert c GALLO Institute of Human Virology University of Maryland Baltimore MD 21201 USA Institute of Human Virology University of Maryland Baltimore MD 21201 USA Department of Microbiology-Immunology University of Maryland School of Medicine Baltimore MD 21201 USA Institute of Human Virology University of Maryland Baltimore MD 21201 USA .Department of Pathology University of Maryland School of Medicine Baltimore MD 21201 USA

critical to the implementation and scale-up of successful antiretroviral therapy worldwide is an understanding of the effcacy, toxicitie and durability of antiretroviral regimens in the specific populations, which the... 详细信息

关键词： HIV commentary on Prevalence and evolution of drug resistance HIV-1 vari-ants in Henan

Bidirectional Erbium Doped Fiber Amplifiers

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High Technology Letters 1995年第1期1卷 66-70页

作者： Zhong, c. Peixuan, J. Ling, L. Peida, Y. Beijing Univ of Posts and Telecommunications Beijing China

Bidirectional EDFAs(Bi-EDFAs)featuring bidirectional signal input are *** and noise performances of Bi-EDFAs are analysed numerically and comparedwith that of other optical *** of Bi-EDFAs in fiber networks and otherf... 详细信息

关键词： Erbium doped fiber amplifiers ASE Bidirectional optical amplifiers

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Ethical challenges in mass drug administration for reducing childhood mortality:a qualitative study

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Infectious Diseases of Poverty 2022年第5期11卷 93-94页

作者： Ahmed Alasmar Alex c.Kong Anthony D.So Matthew Decamp 不详 Division of General Internal Medicine and center for Bioethics and Humanities Department of MedicineUniversity of Colorado School of MedicineUniversity of Colorado Anschutz Medical Campus13080 E.19th AveMail Stop B137AuroraCO 80045USA

Background:Mass drug administration(MDA)of medications to entire at-risk communities or populations has shown promise in the control and elimination of global infectious *** of the broad-spectrum antibiotic azithromycin has demonstrated the potential to reduce childhood mortality in children at risk of premature death in some global ***,MDA of antibiotics raises complex ethical challenges,including weighing near-term benefts against longer-term risks—particularly the development of antimicrobial resistance that could diminish antibiotic efectiveness for current or future *** aim of this study was to understand how key actors involved in MDA perceive the ethical challenges of ***:We conducted 35 semi-structured interviews from December 2020–February 2022 with investigators,funders,bioethicists,research ethics committee members,industry representatives,and others from both highincome countries(HIcs)and low-and middle-income countries(LMIcs).Interview participants were identifed via one of seven MDA studies purposively chosen to represent diversity in terms of use of the antibiotic azithromycin;use of a primary mortality endpoint;and whether the study occurred in a high child mortality *** were analyzed using constructivist grounded theory ***:The most frequently discussed ethical challenges related to meaningful community engagement,how to weigh risks and benefts,and the need to target MDA We developed a concept map of how participants considered ethical issues in MDA for child mortality;it emphasizes MDA’s place alongside other public health interventions,empowerment,and *** over an ethical double standard in weighing risks and benefts emerged as a unifying theme,albeit one that participants interpreted in radically diferent *** thought MDA for reducing child mortality was ethically obligatory;others suggested it was ***:Ethical challenges raised by MDA of antib

关键词： Antimicrobial resistance Decolonizing global health Mass drug administration child mortality Ethics Global health equity

Antioxidant,cytotoxic,and anti-venom activity of Alstonia parvifolia ***

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Asian Pacific Journal of Tropical Biomedicine 2021年第10期11卷 460-468页

作者： Maria carmen S.Tan Mary Stephanie S.carranza Virgilio c.Linis Raymond S.Malabed Yves Ira A.Reyes Francisco c.Franco,Jr. Glenn G.Oyong chemistry Department De La Salle University2401 Taft AvenueManila 1004Philippines Biology Department De La Salle University2401 Taft AvenueManila 1004Philippines Department of chemistry Graduate School of ScienceOsaka UniversityOsaka 563-0034Japan Molecular Science Unit Laboratory Center for Natural Sciences and Environmental ResearchDe la Salle University2401 Taft AvenueManila 1004Philippines

Objective:To evaluate antioxidant,cytotoxic,and anti-venom capacity of crude bark extracts of Alstonia parvifolia ***:Gas chromatography-mass spectrometry(Gc-MS)and energy dispersive X-ray analyses were accomplished to characterize the chemical constituents of Alstonia *** characterization was evaluated using an inhibitory phospholipase A_(2)(PLA_(2))assay,DPPH,and cytotoxicity *** the constituents listed in the Gc-MS analyses,molecular docking was conducted to inspect the binding energies between the chosen compounds and selected PLA_(2) ***:Gc-MS analyses showed that the Alstonia parvifolia crude extract consisted predominantly of acetylmarinobufogenin(14.89%),γ-sitosterol(10.44%),3-O-methyl-D-glucose(5.88%),3,5-dimethoxy-4-hydroxyphenylacetic acid(5.30%),(2α,5α)-17-methoxyaspidofractinin-3-one(AFM)(4.08%),and 2,3,5,6,7,8,9-heptahydro-1-phenyl-5-(p-chlorophenylimino)-1H-benzo[e][1,4]thiazepine(HPT)(1.37%).The principal elemental components of Alstonia parvifolia were ca(4.012%)and K(1.496%),as exhibited by energy dispersive X-ray *** parvifolia showed significant free radical scavenging ability(Ic_(50):0.287 mg/mL)and was non-cytotoxic to normal HDFn cells(Ic_(50)>100μg/mL).Moreover,Alstonia parvifolia was favorably cytotoxic to McF-7(Ic_(50):4.42µg/mL),followed by H69PR,HT-29,and THP-1,with Ic_(50) values of 4.94,5.07,and 6.27µg/mL,*** parvifolia also displayed notable inhibition against PLA_(2) activity of Naja philippinensis Taylor venom with Ic_(50) of(15.2±1.8)μg/*** and cluster analyses projected negative binding energies from AFM(−6.36 to−9.68 kcal/mol),HPT(−7.38 to−9.77 kcal/mol),and acetylmarinobufogenin(−7.22 to−9.59 kcal/mol).These calculations were for the particular interactions of Alstonia parvifolia constituents to PLA_(2) homologues where the utmost affinity was detected in HPT owing to the dipole interactions with amino acid ***:The bark e

关键词： Alstonia parvifolia Merr. Naja philippinensis Taylor Gas chromatography-electron ionization-mass spectrometry Secretory phospholipase A_(2) cytotoxicity assay Anti-venom