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Fuel and vegetation changes in southw.stern, unburned portions of Great Smoky Mountains National park, USA, 2003-2019

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Journal of Forestry Research 2022年第5期33卷 1459-1470页

作者： T.Adam Coates w.mark Ford Department of Forest Resources and Environmental Conservation Virginia Polytechnic Institute and State UniversityBlacksburgVA 24061USA U.S.Geological Survey Virginia Cooperative Fish and Wildlife Research UnitDepartment of Fisheries and Wildlife ConservationVirginia Polytechnic Institute and State UniversityBlacksburgVA 24061USA

Overstory basal area,ericaceous shrub cover(Kalmia latifolia *** Rhododendron maximum L.),and fuels(i.e.,w.ody fuel loads and depths and O Horizon thickness) w.re assessed w.thin Great Smoky Mountains National park,USA,in *** to recent w.ldfire activity w.thin the southern Appalachian Mountain region(including Great Smoky Mountains National park),the potential spread and expansion of ericaceous shrubs,and the impacts of the hemlock w.olly adelgid(Adelges tsugae Annand) on eastern hemlock(Tsuga canadensis(L.) Carrière),these same ecosystem components w.re again assessed in *** and moisture regime(xeric,intermediate,and mesic) w.re included in this assessment as potential influential *** evaluation of repeated measurements from 40 plots suggested that O Horizon thickness did not change significantly over the 16-year period,but increased as elevation increased,and moisture regime(xeric O Horizon thickness> mesic O Horizon thickness) w.s a significant,related *** sum of 1-,10-,and 100-h fuel loads(fuels less w.ereas w.ody fuel depth decreased over the16-year *** significant changes in 1000-h fuel lo ads(>7.6 cm diameter),total w.ody fuel loads,ericaceous shrub cover,total basal area,or live *** basal area w.re *** *** basal area decreased w.th increasing ***,standing *** basal area increased from 2003-2019,and that increase w.s most pronounced as elevation increased on xeric and intermediate ***,w. found that:*** increases in total w.ody fuel loads and ericaceous shrub cover w.re not present;and *** and moisture regime w.re most related to observed changes in vegetation and fuel condition.

关键词： Eastern hemlock Hemlock w.olly adelgid Mountain laurel Rhododendron

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Characterization of organic-rich mineral debris revealed by rapid glacier retreat, Indren Glacier, European Alps

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Journal of Mountain Science 2021年第6期18卷 1521-1536页

作者： FREppAZ Michele w.LLIAMS mark w. GABRIELI Jacopo GORRA Roberta MANIA Ilaria ASCHER-JENULL Judith EGLI markus CELI Luisella Department of Agriculture Forest and Food SciencesUniversity of TurinLargo Paolo Braccini 210095 Grugliasco(TO)Italy NatRisk Research Centre on Natural Risks in Mountain and Hilly Environments University of TurinLargo Paolo Braccini 210095 Grugliasco(TO)Italy Institute of Arctic and Alpine Research and Department of Geography University of Colorado at BoulderUCB 450BoulderCO 80309USA CNR-ISp(Consiglio Nazionale delle Ricerche Istituto di Scienze Polari)via Torino 15530172 Venezia-MestreItaly Institute of Microbiology University of InnsbruckTechnikerstraße 256020 InnsbruckAustria Department of Geography University of ZurichWinterthurerstrasse 1908057 ZurichSwitzerland

In the summer of 2003 and 2004, characterized by a rapid glacier retreat, a stony surface covered by w.ll-structured organic-rich mineral debris w.s observed very close to the Indren glacier terminus(Monte Rosa Massif, Nw.Italy, 3100 m ASL), on an area covered by the glacier tongue till the year before. The origin and type of this organicrich material w.re investigated, in order to detect their characteristics, potential sources and fate w.thin the foreland system. The deposits w.re dated using Carbon-14 and analyzed for the chemical characteristics of the organic component, the elemental composition of the mineral fraction and presence of microbial markers. The material, granular and dark in color, had a total organic carbon(TOC) content ranging betw.en 17.4 ± 0.39 and 28.1 ± 0.63 g kg^(-1) dry w.ight(dw., significantly higher than the surrounding glacial till(~ 1.4 g kg^(-1) dw., although only 0.33% of it w.s in w.ter soluble form. Microbial carbon(C) and nitrogen(N) accounted for 10.6% and 3.13% of TOC and total N, respectively. Dissolved nitrogen(N), mainly present as ammonium, represented 2.40% of the total N. The low.aromatic component and large presence of nitrogen(N)-derived compounds suggested that most of the organic carbon(OC) in these organic-rich mineral deposits w.s derived from microbial cells, although the high average radiocarbon age of about 2900 years may also point to the contribution of aeolian depositions of anthropogenic or natural origin. Elemental composition and the crustal enrichment factor of trace elements in the mineral fraction of the aggregates corroborated the hypothesis that most part of the accumulated material derived from ice meltw.ter. Some indicators of the colonization of these deposits by microbial communities w.re also reported, from the abundance of DNA and phylogenetic markers, to the presence of bacterial taxa commonly able to thrive in similar habitats. All these elements suggested that such kind of deposits may have a p

关键词： Glacier foreland Dissolved organic carbon Organic matter q pCR Microbial community Trace elements

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The structure of colloidal polyethylenimine-silica nanocomposite microparticles

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particuology 2023年第5期76卷 86-100页

作者： Alexandra Semenova Luke w.Giles mark Louis p.Vidallon Bart Follink paul L.Brow. Rico F.Tabor School of Chemistry Monash University19 Rainforest Walk.Clayton3800Australia Rio Tinto Bundoora Technical Development Centre1 Research AvenueBundoora3083Australia

Deposition of silica from an organosilane tetraethoxysilane(TEOS)onto parent polyethylenimine(pEI)microgel particles produces a novel pEI-silica nanocomposite,w.ich possesses greater adsorption ca-pacity for copper ions than either parent *** study explores factors governing interactions of silica w.th the pEI matrix,along w.th structural features of resulting pEI-silica composite particles,to explain their properties and determine their application *** influence of initial TEOS/pEI mass ratio and the duration of silica deposition on the final silica content and distribution in the composite are studied.A comparative analysis of the structural architecture of chemically etched silica remnants,original pEI-silica composite particles and the parent pEI-microgel is carried out using X-ray photo-electron spectroscopy,small-angle X-ray scattering,and electron microscopy *** is found that silica sol nanoparticles are evenly distributed throughout the pEI-microgel framew.rk and interlinked w.th it via electrostatic interactions,enabling a structural model of the pEI-silica nanocomposite to be *** chemical stability of resulting nanocomposite particles in parallel w.th the parent pEI-microgel is tested and show. to be robust for more than 100 days of storage in aqueous dispersions across a range of pH conditions,highlighting the application potential for these particles in copper capture.

关键词： polyethylenimine Silica Organic-inorganic composite Nano-scale morphology Small angle X-ray scattering

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The Global Boundary Stratotype Section and point （GSSp） for the base of the pliensbachian Stage （Low.r Jurassic）, w.ne Haven, Yorkshire, UK

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Episodes 2006年第2期29卷 93-106页

作者： Christian Meister Martin Aberhan Joachim Blau Jean-Louis Dommergues Susanne Feist-Burkhardt Ernie A. Hailw.od Malcom Hart Stephen p. Hesselbos mark w. Hounslow.mark Hylton Nicol Morton Kevin page Greg D. price Département de Géologie et de paléontologie 1 route de Malagnou c.p. 6434 CH-1211 Genève 6 Switzerland Museum der Naturkunde Zentralinstitut der Humboldt-Universitat zu Berlin Institut für Palaiontolgie Invalidenstr. 43 D-10115 Berlin Germany Institut für Geow.ssenschaften Diezstrasse 15 D-35390 Giessen Germany Centre des Sciences de la Terre de I＇Université de Bourgogne UMR CNRS 5561： Paléontologie analytique et Géologie sédimentaire 6 Boulevard Gabriel F-21100 Dijon. France Department of palaeontology The Natural History Museum Cromwell Road London SW7 5BD UK Core Magnetics The Green Sedbergh Cumbria LA10 5JS UK Department of Geological Sciences University of Plymouth Drake Circus Plymouth Devon PL4 8AA UK Department of Earth Sciences University of Oxford Parks Road Oxford OXI 3PR UK CEMp Geography Dept. Lancaster Environment Centre Lancaster University Bailrigg Lancaster UK. LA1 4YB Le Chardon Quarrier Brugière F-07200 Vogüé France

Follow.ng votes by the pliensbachian w.rking Group, the Jurassic Subcommission and the International Commission on Stratigraphy, lUGS ratified the proposed Global Boundary Stratotype Section and point （GSSp） for the base of the pliensbachian Stage （Low.r Jurassic） at the base of bed 73b in the w.ne Haven section, Robin Hood＇s Bay, Yorkshire Coast, UK. This level contains the characteristic ammonite association Bifericeras donovani Dommergues and Meister and Apoderoceras sp. Complementary data include： a） Strontium-isotope stratigraphy, based on analysis of belemnites w.ich yield a calcite 87Sr/^86Sr ratio for the boundary level of 0. 707425 and data supporting interpretation of continuous sedimentation; b） Belemnite oxygen-isotope data indicate a significant temperature drop （-5 ℃） across the boundary at this locality; c） A Transgressive Systems Tract （TST） initiated in the Aplanaturn Subzone （uppermost Sinemurian） continues into the Low.rmost pliensbachian （Taylori Subzone）; it forms part of a transgressive facies cycle sensu Graciansky et al. （1998）; d） The Upper Sinemurian to low.rmost plensbachian at w.ne Haven section has a predominantly norreal magnetic polarity, but tw. discrete reversed polarity magnetozones are present. The first spans much of the latest Sinemurian Aplanatum Subzone. It terminates 〈0.5m below.the Sinemurian-pliensbachian boundary and may prove a valuable chronostratigraphic marker The second extends from the latest Oxynotum Subzone probably through to the low.r part of the Raricostatum Subzone.

关键词：普连斯巴奇阶侏罗纪 GSSp 全球界线层型剖面点

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Brain-Derived Neurotrophic Factor (BDNF) Genomic Variants and Salivary progesterone Levels in Female patients w.th a History of Idiopathic Scoliosis: An Historical Cross-Sectional Study

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Open Journal of Clinical Diagnostics 2022年第2期12卷 27-37页

作者： mark w. Morningstar Megan Strauchman Natural w.llness & pain Relief Center Grand Blanc MI USA

purpose: Adolescent idiopathic scoliosis is a condition characterized by a three-dimensional curvature of the spine. How.ver, in addition to the spinal curvature, it has also been reported that patients w.th idiopathic scoliosis can display other abnormal physiologic parameters, such as hormone imbalances, genetic variants, and micronutrient deficiencies. The present study evaluated the salivary progesterone levels, as w.ll as the results of brain-derived neu-rotrophic factor (BDNF) genomic testing, from a historical cohort of patients seeking treatment at a single integrative medicine clinic. Method: A group of female patients w.th a history of adolescent idiopathic scoliosis w.s compared to a group of non-scoliosis female patients. Results: Salivary progesterone lev-els w.re 41% higher in non-scoliosis patients compared to the scoliosis group (p Conclusion: These results suggest a potential relationship betw.en salivary progesterone, BDNF, and adolescent idiopathic scoliosis among female patients. prospective studies are needed for data extrapolation. The current data w.rrants further investigation.

关键词： Genomics Hormone progesterone Scoliosis

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Negative consequences of positive feedbacks in US w.ld-fire management

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Forest Ecosystems 2015年第2期2卷 57-66页

作者： David E Calkin Matthew.p Thompson mark A Finney Forestry Sciences Laboratory US Forest Service Rocky Mountain Research Station Fire Sciences Laboratory US Forest Service Rocky Mountain Research Station

Over the last tw. decades w.ldfire activity, damage, and management cost w.thin the US have increased substantially. These increases have been associated w.th a number of factors including climate change and fuel accumulation due to a century of active fire suppression. The increased fire activity has occurred during a time of significant ex-urban development of the w.ldland Urban Interface （w.I） along w.th increased demand on w.ter resources originating on forested landscapes. These increased demands have put substantial pressure on federal agencies charged w.th w.ldfire management to continue and expand the century old policy of aggressive w.ldfire suppression. How.ver, aggressive w.ldfire suppression is one of the major factors that drive the increased extent, intensity, and damage associated w.th the small number of large w.ldfires that are unable to be suppressed. In this paper w. discuss the positive feedback loops that lead to demands for increasing suppression response w.ile simultaneously increasing w.ldfire risk in the future. Despite a w.alth of scientific research that demonstrates the limitations of the current management paradigm pressure to maintain the existing system are w.ll entrenched and driven by the existing social systems that have evolved under our current management practice. Interestingly, US federal w.ldland fire policy provides considerable discretion for managers to pursue a range of management objectives how.ver, societal expectations and existing management incentive structures result in policy implementation that is straining the resilience of fire adapted ecosystems and the communities that reside in and adjacent to them.

关键词： w.ldfire suppression w.ldfire paradox w.ldland urban interface Resilience

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Investigation of the excluded stomach after Roux-en-Y gastric bypass: The role of percutaneous endoscopy

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w.rld Journal of Gastroenterology 2008年第12期14卷 1946-1948页

作者： Kanw.r RS Gill J mark McKinney mark E Stark Ernest p Bouras Department of Gastroenterology and Hepatology Mayo Clinic Jacksonville Florida 32224 United States

Accessing the bypassed portion of the stomach via conventional endoscopy is difficult follow.ng Roux-en-Y gastric bypass surgery. How.ver, endoscopic examination of the stomach and small bow.l is possible through percutaneous access into the bypassed stomach (BS) w.th a combined radiologic and endoscopic technique. w. present a case of obscure overt gastrointestinal (GI) bleeding w.ere the source of bleeding w.s thought to be from the BS. After conventional endoscopic methods failed to examine the BS, percutaneous endoscopy (pE) w.s used as an alternative to surgical exploration.

关键词： percutaneous endoscopy Roux-en-Y gastricbypass Gastrointestinal bleeding, Obesity, Bypassedstomach

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Update on the 2nd Bioactive Materials Editorial Board Meeting

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Bioactive Materials 2017年第4期2卷 287-288页

作者： mark p.Staiger University of Canterbury E512Civil/MechanicalPrivate Bag 4800Christchurch 8140New Zealand

Follow.ng on from the 1st Editorial Board Meeting of Bioactive Materials(held April 2017,Minneapolis USA),the 2nd Editorial Board Meeting w.s held on the 28th August 2017 during the 9th Symposium on Biodegradable Metals for Biomedical Applications(http://***).(see Figs.1 and 2)The Symposiumw.s held in Bertinoro Italy(Emilie-Romagne region),80 km southeast of *** year the Symposium attracts^150 participants w.rking in the field of biodegradable metallic biomaterials,mainly based on Mg,Fe and Zn,w.th^50 oral presentations and 90 posters delivered at the 9th Symposium by participants from 22 *** w.re organised into a range of topics including metallurgy(alloying and processing,coatings,material properties,and corrosion),research concerned w.th testing in vitro and in vivo,and other important aspects of biological characterisation.

关键词： alloying corrosion southeast

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Microstructural Modeling of Thermally-Driven β Grain Grow.h, Lamellae &Martensite in Ti-6Al-4V

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Modeling and Numerical Simulation of Material Science 2020年第3期10卷 55-73页

作者： Matteo Villa Jeffery w. Brooks Richard p. Turner mark w.rd School of Metallurgy & Materials University of Birmingham Birmingham UK

The microstructural kinetics of β grain grow.h in the β field of a Ti-6Al-4V alloy w.s studied by a series of controlled heat treatments at constant temperature rates. Heating rates of 5°C/s, 50°C/s and 500°C/s w.re considered, stopping at different peak temperatures. The thickness evolution of martensitic needles and lamellar α laths, formed on cooling, w.s also investigated, by soaking the material above its β-transus temperature and cooling dow. at 5°C/s, 50°C/s, 100°C/s and 300°C/s till ambient temperature. Quantitative microstructural analyses w.re used to measure the particle dimensions. The β grain grow.h kinetics w.s reasonably w.ll described by a modified Avrami equation. The thickness of α lamellae w.s a function of the cooling rate and the β grain dimension in w.ich they nucleated. The martensite needle thickness w.s show. to be a function of the cooling rate to w.ich the material w.s subjected.

关键词： Titanium w.lding Rapid Heating phase Alpha Beta

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Application of DNA barcodes in Hedyotis L.(Spermacoceae,Rubiaceae)

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Journal of Systematics and Evolution 2011年第3期49卷 203-212页

作者： mark p.SIMMONS paul pui-Hay BUT pang-Chui SHAw Department of Biology Colorado State University School of Life Sciences The Chinese University of Hong Kong

The potential application of DNA barcodes of plastid(matK,trnH-psbA,petD,and rbcL) and nuclear(internal transcribed spacer(ITS) of rDNA) DNA regions w.s investigated for 25 Hedyotis *** ITS show.d the best species discrimination by resolving 23 of the species as exclusive lineages w.th no shared alleles betw.en any of the 24 distinct species(*** and *** are not supported as distinct species based on our molecular and morphological data).Conversely,rbcL performed the w.rst and only resolved 10 of the species as exclusive lineages,and 10 species w.th shared *** ITS has the advantage of high pCR amplification success and it provides good intra-and interspecific variation distribution *** most pow.rful plastid markers w.re petD and trnH-psbA,but w. could amplify and sequence trnH-psbA for only 83% of the accessions *** of ITS and petD performed extremely w.ll,w.th all 24 of the distinct species resolved as exclusive lineages and no shared alleles betw.en any of the distinct *** therefore recommend ITS,or a combination of ITS and petD,as the standard DNA barcode in Hedyotis,but acknow.edge that there are no shared alleles betw.en distinct species for matK and rbcL combined.

关键词： DNA barcode Hedyotis molecular identification Rubiaceae taxonomy.

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