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Establishment of Withania somnifera Hairy.Root Cultures for the Production of Withanolide A

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j.urnal of Integrative Plant Biology 2008年第8期50卷 975-981页

作者： Hosakatte N. Murthy.Camelia Dij.stra Paul Anthony.Daniel A. White mike R. Davey.j. Brian Power Eun j. Hahn Kee y. Paek Plant Sciences Division School of Biosciences University of Nottingham Sutton Bonington Campus Loughborough LE12 5RD UK Department of Botany Karnatak University Dharwad 580 003 India Research Center for the Development of Advanced Horticultural Technology Chungbuk National University Cheongju 361-763 Korea Department of Botany Karnatak University Dharwad 580 003 India Food Sciences Division School of Biosciences University of Nottingham Sutton Bonington Campus Loughborough LE12 5RD UK Research Center for the Development of Advanced Horticultural Technology Chungbuk National University Cheongju 361-763 Korea

Withania sominifera （Indian ginseng） was transformed by.Agrobacterium rhizogenes. Explants from seedling roots, stems, hy.ocoty.s, coty.edonary.nodal segments, coty.edons and y.ung leaves were inoculated with A. rhizogenes strain R1601. Hairy.（transformed） roots were induced from coty.edons and leaf explants. The transgenic status of hairy.roots was confirmed by.poly.erase chain reaction using nptll and rolB specific primers and, subsequently. by.Southern analy.is for the presence of nptll and rolB genes in the genomes of transformed roots. Four clones of hairy.roots were established; these differed in their morphology. The doubling time of faster growing cultures was 8-14 d with a fivefold increase in biomass after 28 d compared with cultured, non-transformed seedling roots. MS-based liquid medium was superior for the growth of transformed roots compared with other culture media evaluated （SH, LS and N6）, with MS-based medium supplemented with 40 g/L sucrose being optimal for biomass production. Cultured hairy.roots sy.thesized withanolide A, a steroidal lactone of medicinal and therapeutic value. The concentration of withanolide A in transformed roots （157.4 μg/g dry.weight） was 2.7-fold more than in non-transformed cultured roots （57.9 μg/g dry.weight）.

关键词： Agrobacterium rhizogenes hairy.(transformed) roots Indian ginseng transformation withanolide A

Biological and Molecular Geochemical Evidence for Dinoflagellate Ancestors in the Upper Sinian-Cambrian

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Acta Geologica Sinica(English Edition) 2000年第4期74卷 740-747页

作者： j.mike MOLDOWAN Department of Geological and Environmental Sciences Stanford University CA 94305 USA

Dinoflagellates are single celled organisms that reflect the ecological conditions in modern oceans and lakes. Their earliest undisputed fossil record suggests that dinoflagellates originated from the Middle Triassic (c. 240 Ma ago). However, the presence of molecular biomarkers (dinosterane, 4α-methy.-24-ethy.cholestane and tria-romatic dinosteroids) in rock extracts and coccoid dinoflagellate fossils from the upper Sinian to Cambrian of the Tarim basin confirms the hy.othesis that dinoflagellates have an ancient origin, and predate the oldest undisputed dinoflagellate fossils at least by.300 Ma, as early.as the late Sinian-Cambrian.

关键词： dinoflagellates dinosterane triaromatic dinosteroids Cambrian

Towards interruption of schistosomiasis transmission in sub-Saharan Africa:developing an appropriate environmental surveillance framework to guide and to support‘end game’interventions

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Infectious Diseases of Poverty 2017年第1期6卷 78-88页

作者： j.Russell Stothard Suzy.j.Campbell mike y.Osei-Atweneboana Timothy.Durant Michelle C.Stanton Nana-Kwadwo Biritwum David Rollinson Dieudonne R.Eloundou Ombede Louis-Albert Tchuem-Tchuente Department of Parasitology Liverpool School of Tropical MedicinePembroke PlaceLiverpool L35QAUK Department of Environmental Biology.and Health Council for Scientific and Industrial Research-Water Research InsituteP.O.Box M 32AccraGhana Neglected Tropical Diseases Programme Ghana Health ServicesAccraGhana Department of Life Sciences Natural History MuseumCromwell RoadLondon SW75BDUK Centre for Schistosomiasis and Parasitology YaoundeCameroon Laboratory.of Parasitology.and Ecology Faculty of SciencesUniversity of YaoundeIYaoundeCameroon National Programme for the Control of Schistosomiasis and Intestinal Helminthiasis Ministry of Public HealthYaoundeCameroon

Schistosomiasis is a waterborne parasitic disease in sub-Saharan Africa,particularly.common in rural populations living in impoverished *** the scale-up of preventive chemotherapy.national campaigns will transition from morbidity.to transmission-focused interventions thus formal investigation of actual or expected declines in environmental transmission is needed as‘end game’scenarios ***,there are no international or national guidelines to do so in sub-Saharan *** article therefore provides an introduction to key.practicalities and pitfalls in the development of an appropriate environmental surveillance *** this context,we discuss how strategies need to be adapted and tailored to the local level to better guide and support future interventions through this *** detection of egg-patent infection in people becomes rare,careful sampling of schistosome larvae in freshwater and in aquatic snails with robust species-specific DNA assay. will be *** metrics,derived from observed prevalence(s)as compared with predetermined thresholds,could each provide a clearer insight into contamination-and exposure-related *** could be twofold,first to certify.areas currently.free from schistosomiasis transmission or second to red-flag recalcitrant locations where extra effort or alternative interventions are needed.

关键词： Environmental monitoring Freshwater snails eDNA WASH Zoonosis

Creep-fatigue lives prediction and sensitivity.study.of 316H at 550 ℃

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Acta Metallurgica Sinica(English Letters) 2011年第2期24卷 132-140页

作者： Zhichao FAN David j.Smith Xuedong CHEN mike W Spindler Hefei General Machinery.Research Institute Hefei 23-0031 China University.of Bristol Bristol BS8 1TR UK British Energy Gloucester GL4 3RS UK

In Volume 2/3 of R5 ＂An assessment procedure for the high temperature response of structures＂, the strain based ductility.exhaustion method is suggested to calculate the creep damage of stress concentration region, which involves description of creep dwell initial stress, stress drop and creep ductility. Considering lots of uncertainty.existed in these assessment, some sensitivity.analy.is is required in R5 procedure to ensure the conservatism of assessment results. In this paper, laboratory.creep-fatigue test data of 316H at 550 ℃ with different loading conditions are selected as a special case to investigate whether the basic R5 approach is conservative, and the different material data combinations of cy.lic stress-strain, creep deformation and creep ductility.are used to identify.those significant parameters affecting the assessment results. The analy.ical results indicate that the creep deformation model and creep ductility.data are more significant to the results comparing with cy.lic stress-strain data. If the upper bound of creep deformation law and lower bound of creep ductility.data are used to predict their creep-fatigue lives, the degree of conservatism can be as large as a factor of -300, but if the modified creep deformation model and cast specific ductility.data are used, very.well prediction results can be gained within a factor of ±2.0 although there is slight non-conservatism.

关键词： Creep Fatigue Damage Life prediction Sensitivity.study

How to Connect the Gap between Clinical Trials and Clinical Practice

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Chinese j.urnal of Integrative Medicine 2008年第4期14卷 309-311页

作者：商洪才徐宏娟陈静张伯礼李幼平 mike j.Clarke West Chin'a Hospital of Sichuan University Academy.of TCM in Tianj.n University.of Traditional Chinese Medicine Evidence-Based Medicine Centre in Tianj.n University.of TCM Heart Department in Tianj.n Chest Hospital West China Hospital of Sichuan University UK Cochrane Centre OxfordOX27LGUK

Clinical research methods have been rapidly.developing, and the design of clinical trials including traditional Chinese medicine is advancing. To a certain extent, all of these ensure that the results of clinical research are obj.ctive and scientific, but whether these results and the resulting guidelines or consensus have much practical significance on clinical practice is still controversial. The authors engage in both clinical practice and clinical research; they.strongly.feel that it is necessary.to discuss the relationship between clinical trials and clinical practice. This essay.discusses this relationship in four parts.

关键词： clinical trials clinical practice external validity

Adult bobcat(Ly.x rufus)habitat selection in a longleaf pine savanna

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Ecological Processes 2018年第1期7卷 206-217页

作者： Andrew R.Little L.mike Conner Michael j.Chamberlain Nathan P.Nibbelink Robert j.Warren Warnell School of Forestry.and Natural Resources University of Georgia180 E.Green StAthensGA 30602USA j.seph W.j.nes Ecological Research Center at Ichauway NewtonGeorgia 39870USA

Background:Pine savannas are primarily.managed with frequent prescribed fire(≤3 y.ars)to promote diversity.of flora and fauna,and to maintain open,park-like conditions needed by.species such as the endangered red-cockaded woodpecker(Picoides borealis).However,a knowledge gap exists in our understanding of bobcat(Ly.x rufus)habitat selection in longleaf pine savannas and research is warranted to direct our future management ***:We examined bobcat habitat selection in a pine savanna managed with frequent fires at two spatial scales(i.e.,study.area boundary.hereafter,landscape scale])and annual area of use[95%kernel density.local scale],and assessed effects of prescribed fire on bobcat habitat ***,we monitored 45 bobcats(16 males and 29 females)during 2001–***:We found differential habitat selection by.*** the landscape scale,female bobcats were closer to mixed pine-hardwoods,y.ung pine,and secondary.roads,but farther from mature pine and hardwoods stands relative to *** found no difference in selection of agriculture,shrub-scrub,and primary.roads between *** the annual area of use scale,female bobcats were closer to secondary.roads,but farther from agriculture and shrub-scrub relative to *** found no difference in selection of mature pine,mixed pine-hardwoods,hardwoods,y.ung pine,and primary.roads between *** primarily.selected for stands burned≤1.1 y.ars ***:Our results show that bobcats exploit a broad range of habitat ty.es in pine landscapes managed with frequent fire and commonly.use recently.burned stands(≤1.1 y.ar post-fire),suggesting prey.in many.areas of this sy.tem are at risk of bobcat ***,we suggest land managers consider scale of selection by.bobcats when developing habitat management strategies.

关键词： Georgia Habitat selection Ly.x rufus Pinus palustris Prescribed fire

3rd ANtarctic Gravity.Wave Instrument Network(ANGWIN)Science Workshop

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Advances in Atmospheric Sciences 2017年第1期34卷 1-3页

作者： Tracy.MOFFAT-GRIFFIN mike j.TAy.OR Takuj. NAKAMURA Andrew j.KAVANAGH j.Scott HOSKING Andrew ORR Britsh Antarctic survey High CrossCambridge CB30ETUK Utah State University LoganUT84322USA National Institute of Polar Research Tachikawa-shiTokyo 190-8518Japan

1. Overview The 3rd ANtarctic Gravity.Wave Instrument Network （ANGWIN） science workshop was held on 12-14 April 2016 in Cambridge, UK. ANGWIN is a highly.successful grassroots program that was started in 2011 （in the Cornish English dialect ANGWIN means ＂the white＂）. Although ini- tially.focused on the Antarctic, we now aim to develop collaborations in both polar regions.

关键词： ANGWIN)Science Workshop Wave

The small hive beetle Aethina tumida： A review of its biology.and control measures

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Current Zoology 2013年第5期59卷 644-653页

作者： Andrew G. S. CUTHBERTSON Maureen E. WAKEFIELD Michelle E. POWELL Gay.MARRIS Helen ANDERSON Giles E. BUDGE j.mes j. MATHERS Lisa F.BLACKBURN mike A. BROWN The Food and Environment Research Agency Sand Hutton York YO41 1LZ UK

The small hive beetle Aethina tumida is an endemic parasitic pest and scavenger of colonies of social bees indigenous to sub-Saharan Africa. In this region this species rarely.inflicts severe damage on strong colonies since the bees have developed strategies to combat them. However, A. tumida has since ＇escaped＇ from its native home and has recently.invaded areas such as North America and Australia where its economic impact on the apiculture industry.has been significant. Small hive beetle, should it become established within Europe, represents a real and live threat to the UK bee keeping industry. Here we review the biology.and current pest status of A. tumida and up to-date research in terms of both chemical and biological control used against this honey.bee pest [Current Zoology.59 （5）： 644-653, 2013].

关键词： Aethina tumida Pesticides Biological control Population development Honey.bees

Efficiency.of soil-applied ^(67)Zn-enriched fertiliser across three consecutive crops

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Pedosphere 2021年第4期31卷 531-537页

作者： Edson M.MATTIELLO Eduardo L.CANCELLIER Rodrigo C.DA SILVA Fien DEGRy.E Rosly. BAIRD mike j.MCLAUGHLIN Department of Soil Science Universidade Federal de ViçosaViçosaMinas Gerais(Brazil) Department of Soil Science Universidade Federal de LavrasMinas Gerais(Brazil) The University.of Adelaide School of AgricultureFood and WineFertiliser Technology Research CentrePMB 1Waite CampusGlen Osmond SA 5064(Australia)

A very.small amount of applied zinc(Zn) is taken up by.crops, resulting in low recovery.by.plants. Adding elemental sulphur to zinc oxide(ZnO) fertiliser could improve Zn solubilisation and exert a higher residual effect on crops than soluble Zn sources. We produced an isotopically.labelled Zn-elemental sulphur fertiliser and evaluated its performance in comparison to traditional Zn sources during sequential crop cultivation. Three ^(67)Zn-labelled fertilisers,ZnO, zinc sulphate(ZnSO_(4)), and ZnO co-granulated with elemental sulphur(ZnOS^(0)), were soil applied, and their contributions to the uptake of Zn by.three consecutive crops, wheat, ry.grass, and corn, were assessed in a 294-d pot experiment. The contributions of Zn fertilisers followed the order: ZnSO_(4) > ZnO= ZnOS^(0). The relative contributions of Zn fertilisers were lower in the first crop than in the subsequent crops. The overall recovery.of applied Zn by.the three crops was higher for ZnSO_(4) than for ZnO and ZnOS^(0), reaching 1.56%, 0.45%, and 0.33% of the applied Zn, respectively. Zinc recovery.by.plants was very.low, regardless of the source of Zn. Adding elemental sulphur to ZnO did not increase its effectiveness up to 294 d after application. Fertiliser contribution was higher for the subsequent crops than for the initial crop, indicating the importance of assessing the residual effects of Zn fertilisers.

关键词： agronomic biofortification elemental sulphur fertilizer residual effect plant uptake Zn bioavailability Zn fertilization Zn source