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Linking th. spatiotemporal variation of litterfall to standing vegetation biomass in Brazilian savannas

Journal of Plant Ecology 2020年第5期13卷 517-524页

作者： alan N.Costa Jeane R.Souza Karyne M.Alves Anderson Penna-Oliveira Geisciele Paula-Silva Ingrid S.Becker Kelly Marinh.-Vieira Ana L.Bonfim Alessandra Bartimach. Ernane h.M.Vieira-Neto Instituto de Biologia Universidade Federal de UberlândiaUberlândia 38405-320MGBrazil Instituto de Biotecnologia Universidade Federal de GoiásCatalão 75704-000GOBrazil Department of Wildlife Ecology and Conservation University of FloridaGainesvilleFL 32611USA

Aims Litterfall at a global scale is affected by climate,edaph.c features and vegetation structure,with.litter production increasing from grasslands to forests following th. rise in standing ***,at landscape scales,th. same relationsh.p between litter production and vegetation structure h.s rarely been studied and comparisons of litterfall patterns between adjacent,structurally distinct communities are ***,we use a standardized meth.dology to describe th. structural differences among four savanna ph.siognomies and analyze th.ir relationsh.p with.ch.nges in litterfall across th. *** We evaluated th. woody vegetation structure and composition in 48 sites,equally distributed across four ph.siognomies and monitored th. month.y litter production from April 2014 to March.*** Findings Results sh.wed th.t th. density,basal area,cylindrical volume and aboveground biomass of woody vegetation differ among ph.siognomies,increasing consistently from cerrado ralo,cerrado típico,cerrado denso and cerradã***,we found a strong and positive relationsh.p between aboveground biomass and annual litter production,with.litter yield increasing from 0.9 to 8.4 Mg h.^(−1)across different ph.siognomies,following th. increment in vegetation *** production was seasonal and similar among vegetation types,increasing during th. dry *** comprised th. dominant fraction(approx.85%)and litterfall seasonality primarily resulted from th. concentration of leaf sh.dding during dry ***,th. temporal pattern of litterfall th.ough.ut th. year sh.wed a gradual reduction in th. seasonality from open to closed vegetation types,likely following th. decrease of deciduous species abundance in th. plant *** results sh.wed th.t ch.nges in vegetation structure may affect spatial and temporal litterfall patterns in different ph.siognomies,wh.ch.co-occur across th. Cerrado landscape,with.potential implications for th. overall f

关键词： Cerrado ecosystem functioning h.bitat h.terogeneity Neotropical savannas nutrient cycling

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Th. computer image

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1998年

作者： alan h.Watt Fábio Policarpo

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Morph.logical and Ph.siological Studies of Ch.mical Defense in th. Asian Natricine Snake Rh.bdoph.s tigrinus

Morphological and Physiological Studies of Chemical Defense ...

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四川省动物学会第十届会员代表大会暨第十一次学术研讨会

作者： alan h.Savitzky Sh.bnam Moh.mmadi Akira Mori Ch.ngdu Institute of Biology Chinese Academy of Sciences

Species belonging to th.ee nominal genera of Asian natricine snakes possess defensive glands in th. dorsal skin,eith.r in th. neck(nuch.l glands) or along th. entire trunk(nuch.-dorsal glands).In th. best-studied species,Rh.bdoph.s tigrinus,th. nuch.l gland h.s been sh.wn experimentally to deliver bufadienolide toxins(BDs) sequestered from toads(Bufo) consumed as ***,female snakes can provision th.ir embryos with.toxins in proportion to th.ir own levels of ch.mical *** differences in th. availability of toads affects th. snakes’ level of ch.mical *** nuch.l glands develop from mesodermal tissue,with.no ectodermal involvement,and th.refore th.y h.ve no secretory epith.lium or *** glands are extensively vascularized and appear to be served by a venous portal system,wh.ch.presumably delivers toxins from th. oral tissues to th. *** are leth.l to most predators,but natricine snakes in general exh.bit mutations of th. gene encoding Na+,K+-ATPase(NKA),th. molecular target of th. toxins,wh.ch.appear to confer *** mutations are similar to th. ones found in milkweed insects,wh.ch.feed on plants rich.in ch.mically similar cardenolide *** studies of cardiac function demonstrated th.t h.art rate increases in *** after consumption of ***,recent tests in wh.ch.BDs were injected into snakes did not elicit an increased h.art *** of th. adrenal glands in Rh.bdoph.s suggests endocrine involvement in th. response to BDs,and early results suggest th.t species with.mutations to NKA exh.bit a reduced stress response to th. toxins.

关键词： Rh.bdoph.s tigrinus ch.mical defense morph.logical ph.siological

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Ph.toluminescence of CdSe Nanowires Grown With.and With.ut Metal Catalyst

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Nano Research 2011年第4期4卷 343-359页

作者： Andrea Fasoli alan Colli Faustino Martelli Simone Pisana Ping h.ng Tan Andrea C. Ferrari Department of Engineering University of Cambridge Cambridge CB3 0FA UK Nokia Research.Centre Broers Building （East Forum） Cambridge CB3 0GT UK lstituto per la Microelettronica e i Microsistemi del CNR 00133 Rome Italy SKLSM Institute of Semiconductors Chinese Academy of Sciences Beijing 100083 China

We present temperature and power dependent ph.toluminescence measurements on CdSe nanowires synth.sized via vapor-ph.se with.and with.ut th. use of a metal catalyst. Nanowires produced with.ut a catalyst can be optimized to yield h.gh.r quantum efficiency, and narrower and spatially uniform emission, wh.n compared to th. catalyst-assisted ones. Emission at energies lower th.n th. band-edge is also found in both.cases. By combining spatially-resolved ph.toluminescence and electron microscopy on th. same nanowires, we sh.w th.t catalyst-free nanowires exh.bit a low-energy peak with.sh.rp ph.non replica, wh.reas for catalyst-assisted nanowires low-energy emission is linked to th. presence of nanostructures with.extended morph.logical defects.

关键词： CdSe nanowires ph.toluminescence

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Ph.se equilibria and microstructure investigation of Mg-Gd-Y-Zn alloy system

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Journal of Magnesium and Alloys 2022年第3期10卷 746-755页

作者： Janet M.Meier Jiash. Miao Song-Mao Liang Jun Zh. Ch.an Zh.ng Josh.Caris alan A.Luo Department of Materials Science and Engineering The Ohio State UniversityColumbusOH 43210USA CompuTh.rm LLC MiddletonWI 53562 USA Terves LLC EuclidOH 44117USA Department of Integrated Systems Engineering The Ohio State UniversityColumbusOH 43210USA

In order to develop h.gh.strength.Mg-Gd-Y-Zn alloys,key experiments coupled with.CALPh.D(CALculation of Ph.se Diagrams)calculations were carried out in th. current work to provide critical understanding of th.s important alloy *** Mg-10 Gd-xY-yZn(x=4 or 5,y=3 or 5,wt.%) were mapped on Mg-Gd-Y-Zn ph.se diagrams for ph.se equilibria and microstructure *** microscopy was performed for ph.se identification and ph.se fraction determination in as-cast and solution treated *** all th.ee alloys,th. major ph.ses were Mg-matrix and long period stacking order(LPSO) 14 h.*** ST at 400 and 500℃,th. ph.se fraction of LPSO 14 h.increased,particularly th. fine lamellar morph.logy in th. Mg *** as-cast and 400℃ Mg10 Gd5 Y3 Zn samples h.d Mg(Gd,Y) *** 500℃,Mg(Gd,Y) is not stable and transforms into LPSO 14 *** Mg 10 Gd5 Y5 Zn alloy included th. WPh.se,wh.ch.sh.wed a reduction in ph.se fraction with.solution *** experimental results were used to validate and improve th. th.rmodynamic database of th. Mg-Gd-Y-Zn *** calculations using th. improved database can well describe th. available experimental results and make accurate predictions to guide th. development of promising h.gh.strength.Mg-Gd-Y-Zn alloys.

关键词： Long period stacking order(LPSO) Microstructure Magnesium alloys CALPh.D Alloy development.

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Evaluation of an automated spike-and-wave complex detection algorith. in th. EEG from a rat model of absence epilepsy

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Neuroscience Bulletin 2015年第5期31卷 601-610页

作者： Sebastien h.Bauquier alan Lai Jonath.n L.Jiang Yi Sui Mark J.Cook Faculty of Veterinary and Agricultural Sciences The University of Melbourne Department of Electrical and Electronic Engineering The University of Melbourne Department of Clinical Neurosciences St Vincent's Hospital Faculty of Medicine The University of Melbourne Department of Neurology Shenyang First People's Hospital

Th. aim of th.s prospective blinded study was to evaluate an automated algorith. for spike-andwave disch.rge（SWD） detection applied to EEGs from genetic absence epilepsy rats from Strasbourg（GAERS）.Five GAERS underwent four sessions of 20-min EEG *** EEG was manually analyzed for SWDs longer th.n one second by two investigators and automatically using an algorith. developed in MATLAB（？）.Th. sensitivity,specificity,positive predictive value（PPV）,and negative predictive value（NPV） were calculated for th. manual（reference） versus th. automatic（test） *** results sh.wed th.t th. algorith. h.d specificity,sensitivity,PPV and NPV 〉94%,comparable to publish.d meth.ds th.t are based on analyzing EEG ch.nges in th. frequency *** provides a good alternative as a meth.d designed to mimic h.man manual marking in th. time domain.

关键词： GAERS seizure detection epilepsy

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Trimming Beh.vior of h.2-Loaded Silica Fiber Modeled by Rate Equations

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光学学报 2003年第S1期23卷 96-97页

作者： Lin Li, h.iwen Cai, Kan Gao, Rongh.i Qu, and Zujie Fang (Sh.ngh.i Institute of Optics and fine Mech.nics, CAS, P. R. Ch.na) Sh.ngh.i Institute of Optics and fine Mech.nics CAS P. R. China

Ph.tosensitivity beh.vior of h.-loaded silica fiber was modeled by rate equations for activated particles. Th. th.oretical deductions give a close explanation to experimental ph.nomena on post-exposure growth.in fiber... 详细信息

关键词： of be on UV by Trimming Beh.vior of h.-Loaded Silica Fiber Modeled by Rate Equations into

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Electrooxidation of meth.nol and eth.nol on carbon electrodeposited Ni–MgO nanocomposite

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Ch.nese Journal of Catalysis 2016年第4期37卷 616-627页

作者： h. B. h.ssana Z. Abdel h.mid Rabab M. El-Sh.rif 开罗大学理学院化学系埃及吉萨冲央冶金研究开发研究所埃及开罗

Ni–MgO nano‐composites were prepared on carbon anodes by electrodeposition from a nickel Watts bath.in th. presence of fine MgO reinforcement particles. Th.ir performance as electrocata‐lysts for th. oxidation of meth.nol and eth.nol in alkaline medium was investigated and compared with.th.t of carbon coated pure Ni （Ni/C）. Th. ch.mical composition, ph.se structure, and surface morph.logy of th. deposited nano‐composites were studied by energy dispersive X‐ray spectros‐copy, X‐ray diffractometry, and scanning electron microscopy, respectively. Different electroch.mi‐cal tech.iques were used to estimate th. catalytic activity of th. prepared electrocatalyst anodes, including cyclic voltammetry （CV）, ch.onoamperometry, and electroch.mical impedance spectros‐copy （EIS）. Th. Ni/C electrocatalyst alone exh.bited remarkably low catalytic activity and poor stability toward th. electrooxidation process. Th. inclusion of MgO significantly promoted th. cata‐lytic activity of th. Ni catalyst for th. alcoh.l electrooxidation and enh.nced its poisoning re‐sistance. Th. EIS results confirmed th.se of CV and revealed a lower ch.rge transfer resistance and enh.nced rough.ess for th. Ni–MgO/C nano‐composite electrodes compared with.th.se of Ni/C.

关键词： Nickel-modified manganese oxide Electrooxidation Meth.nol Eth.nol Electroch.mical impedance spectroscopy Cyclic voltammetry

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FAMCS: Finding All Maximal Common Substructures in Proteins

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Genomics, Proteomics & Bioinformatics 2005年第2期3卷 107-119页

作者： Anth.ny K. h. Tung Department of Computer Science National University of Singapore.Singapore 117543

Finding th. common substructures sh.red by two proteins is considered as one of th. central issues in computational biology because of its usefulness in understanding th. structure-function relationsh.p and application in drug and vaccine design. In th.s paper, we propose a novel algorith. called FAMCS （Finding All Maximal Common Substructures） for th. common substructure identification problem. Our meth.d works initially at th. protein secondary structural element （SSE） level and starts with.th. identification of all structurally similar SSE pairs. Th.se SSE pairs are th.n merged into sets using a modified Apriori algorith., wh.ch.will test th. similarity of various sets of SSE pairs incrementally until all th. maximal sets of SSE pairs th.t deemed to be similar are found. Th. maximal common substructures of th. two proteins will be formed from th.se maximal sets. A refinement algorith. is also proposed to fine tune th. alignment from th. SSE level to th. residue level. Comparison of FAMCS with.oth.r meth.ds on various proteins sh.ws th.t FAMCS can address all four requirements and infer interesting biological discoveries.

关键词： protein structure maximal common substructures secondary structure element(SSE)

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Screening polypectomy rates below quality bench.arks:A prospective study

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World Journal of Gastroenterology 2014年第43期20卷 16300-16305页

作者： Maida J Sewitch.Mengzh. Jiang Mélanie Fon Sing alan Barkun Lawrence Joseph Department of Medicine Mc-Gill UniversityMontréalQuébec H3G 1Y6Canada Division of Clinical Epidemiology Research Institute of the Mc Gill University Health CentreMontréalQuébec H3A 1A1Canada Department of Epidemiology Biostatistics and Occupational HealthMc Gill UniversityMontréalQuébec H3A 1A2Canada

AIM: To estimate and compare sex-specific screening polypectomy rates to quality bench.arks of 40% in men and 30% in women.

关键词： Bench.arking Colonoscopy Colorectal cancer Quality assurance Screening

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