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Cane toads beneath bird rookeries： utilization of a natural disturbance by an invasive species

Current Zoology 2018年第4期64卷 433-439页

作者： damian C. LETTOOF Jessica A. LYONS richard SHINE Grdgoire MANIEL Martin MAYER daniel J, d.NATUSCHa School of Life and Environmental Sciences University of Sydney NSW 2006 Australia Resource Evaluation and development Bamaga QLD 4876 Australia 87 Cours Aristide Briand 33000 Bordeaux France Faculty of Arts and Sciences University College of Southeast Norway Bei Telemark Norway

Many invasive species exploit anthropogenically disturbed habitats, but most of those taxa evolved long before humans. Presumably, then, an ability to use natural （non-anthropogenic） disturbances pre-adapted invaders to a world later degraded by people. Studies on invasive species in naturally disturbed habitats thus can clarify the ancestral niche of invaders. In the Australian tropics, metallic starlings Aplonis metallica nest communally in emergent rainforest trees during the wet-season, and invasive cane toads Rhinella marina join other predators （mammals, birds, reptiles, and other anurans） to exploit the food resources beneath those trees. Compared to conspecifics found along nearby roads through the forest, cane toads beneath bird-nesting trees occur at higher densities, and are smaller in body size. The sex ratio is female-biased, and recapture records suggest that fe- males may be philopatric at these sites （whereas recaptures were rare for both sexes found along the roads）. Some toads were found under the same trees in successive wet-seasons. Spooling showed that distances moved per night were similar along the road versus under the trees, but toads under trees showed lower net displacements. diets also differed （based upon scat analysis）, with tree toads feeding more on beetles and less on ants. These nutrient-rich hotspots are ex- ploited primarily by adult females and juvenile toads, whereas adult males congregate at breeding sites. By magnifying pre-existing intraspecific divergences in habitat use, bird rookeries may en- hance population viability of cane toads by enabling critical age and sex classes to exploit food- rich patches that are rarely used by adult males.

关键词： ancestral niche communal nesting niche partitioning pre-adaptation spatial ecology

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Combining X-ray microtomography with computer simulation for analysis of granular and porous materials

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Particuology 2010年第2期8卷 81-99页

作者： Roberto Moreno-Atanasio richard A. Williams Institute of Particle Science and Engineering School of Process Environmental and Materials Engineering University of Leeds Leeds LS2 9JT UK

The use of X-ray microtomographic （XMT） methods in analysing particulate systems has expanded rapidly in recent years with the availability of affordable desk-top apparatus. This review presents a summary of the major applications in which computer simulations are explicitly coupled with XMT in the area of granular and porous materials. We envisage two main ways of establishing the coupling between both techniques, based on the transference or exchange of information by using physical or geometrical parameters （i.e. a parametric link through fitting to a process model） or through the direct use of3d XMT digital images （i.e. comparing image pixels and features directly）. Examples of coupled applications are shown for the study of transport properties of rocks, particle packing, mechanical loading and sintering. Often, the link between XMT and computer simulations is based on visual comparisons and we conclude that the use of quantitative parameters such as the number of interparticle contacts, force networks or granule shape to link both techniques is still underrepresented in the literature. Strategies to provide a more robust and quantitative approach to optimise the information obtained from such tomography analyses are proposed. 2010 Chinese Society of Particuology and Institute of Process Engineering, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.

关键词： X-ray microtomographyGranular flowComputer modellingLattice Boltzmann methoddiscrete element method

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From dirac’s Aether to the dirac Equation

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Journal of High Energy Physics, Gravitation and Cosmology 2024年第4期10卷 1450-1466页

作者： richard d. Bateson Cavendish Laboratory Cambridge UK

In 1951, dirac proposed a formalism for a Lorentz invariant Aether with a vacuum state that contains all possible velocity states at each space-time point. dirac showed no explicit path from the Aether towards the Quantum Mechanics. In this paper, we demonstrate that dirac’s proposed Aether can be described by a lattice of possible events in space-time built in the local Lorentz frame. The idealised case of single velocity state leads to the famous dirac equation for a plane wave state and is compatible with quantum statistics. On the lattice, possible space-time events are connected by the dirac spinors which provide the probability of observing an event. The inertial mass of a particle is shown to be equivalent to the density of possible events on the lattice. Variation of the lattice density of events modifies the metric and provides a space-time curvature leading to the Hilbert action associated with general relativity. In classical limit, the perturbation in the density of possible events of the Aether is proportional to the Newtonian gravitational potential.

关键词： dirac Aether Lorentz Invariance dirac Equation Quantum Mechanics Space-Time Lattice dirac Spinors Inertial Mass Metric Modification Space-Time Curvature General Relativity

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Reappraising the P-T evolution of the Rogaland-Vest Agder Sector,southwestern Norway

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Geoscience Frontiers 2017年第1期8卷 1-14页

作者： Eleanore Blereau Tim E.Johnson Chris Clark richard J.M.Taylor Peter d.Kinny Martin Hand department of Applied Geology The Institute for Geoscience Research(TIGeR)Curtin University Centre for Tectonics Resources and Exploration(TRaX)School of Earth and Environmental SciencesUniversity of Adelaide

The Rogaland-Vest Agder Sector of southwestern Norway comprises high-grade metamorphic rocks intruded by voluminous plutonic bodies that include the ~1000 km^2 Rogaland Igneous Complex（RIC）.New petrographic observations and thermodynamic phase equilibria modelling of three metapelitic samples collected at various distances（30 km,10 km and ~ 10 m） from one of the main bodies of RIC anorthosite were undertaken to assess two alternative P-T-t models for the metamorphic evolution of the *** results are consistent with a revised two-phase *** metamorphism followed a clockwise P-T path reaching peak conditions of ~ 850-950 ℃ and ~7-8 kbar at ~1035 Ma followed by high-temperature decompression to ~5 kbar at ~950 Ma,and resulted in extensive anatexis and melt loss to produce highly residual *** emplacement of the RIC at ~930 Ma caused regional-scale contact metamorphism that affected country rocks 10 km or more from their contact with the *** thermal overprint is expressed in the sample proximal to the anorthosite by replacement of sillimanite by coarse intergrowths of cordierite plus spinel and growth of a second generation of garnet,and in the intermediate（10 km） sample by replacement of sapphirine by coarse intergrowths of cordierite,spinel and *** formation of late biotite in the intermediate sample may suggest the rocks retained small quantities of melt produced by regional metamorphism and remained at temperatures above the solidus for up to 100 *** results are more consistent with an accretionary rather than a collisional model for the Sveconorwegian Orogen.

关键词： UHTPhase equilibria modellingRogaland Igneous ComplexTHERMOCALCSveconorwegian Orogen

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Reconstruction using a pedicled upper arm fillet flap after excision of a malignant peripheral nerve sheath tumor: A case report

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World Journal of Clinical Cases 2014年第12期2卷 899-902页

作者： Parteek Singla Swapnil d Kachare Timothy L Fitzgerald richard S Zeri Enamul Haque Brody School of Medicine East Carolina University Greenville NC 27834 United States department of Surgery The Brody School of Medicine East Carolina University Greenville NC 27834 United States

Non-salvageable extremities have been utilized for harvesting fillet flaps as part of the "spare parts" concept in traumatic and oncologic settings. Here we report on the use of a pedicled fillet flap of the upper arm for chest wall reconstruction after excision of a malignant peripheral nerve sheath tumor in a patient with neurofibromatosis. Pedicled flaps as part of the "spare parts" concept provide the advantage of reduced donor-site morbidity, immediate closure, intact vasculature, and adequate soft tissue coverage of large defects. Malignant peripheral nerve sheath tumor is a rare aggressive tumor with a poor prognosis that may result in large defects post resection. Limited data describes the use of pedicled fillet flaps of the upper extremity. We report the use of a pedicled fillet flap of the upper arm as a viable option that can be successfully used for coverage of soft tissue defects of the shoulder and chest wall post complex resections in an oncologic setting.

关键词： Reconstruction Flaps Neurofibromatosis Malignant Peripheral Nerve Sheath Tumor Sarcoma

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Relating environmental variables with aquatic community structure in an agricultural/urban coldwater stream

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Ecological Processes 2021年第1期10卷 481-499页

作者： daniel T.L.Myers richard R.Rediske James N.McNair Aaron d.Parker E.Wendy Ogilvie Annis Water Resources Institute Grand Valley State University740 W Shoreline DriveMuskegonMI 49401USA. Michigan department of Environment Great Lakesand Energy525 W Allegan StreetLansingMI 48909USA. Grand Valley Metropolitan Council 678 Front Avenue NWSuite 200Grand RapidsMI 49504USA.

Background:Urban areas are often built along large rivers and surrounded by agricultural *** may lead to small tributary streams that have agricultural headwaters and urbanized lower *** study objectives assessed are as follows:(1)landscape,geomorphic,and water quality variables that best explained variation in aquatic communities and their integrity in a stream system following this agricultural-to-urban land use gradient;(2)ways this land use gradient caused aquatic communities to differ from what would be expected for an idealized natural stream or other longitudinal gradients;and(3)whether the impacts of this land use gradient on aquatic communities would grow larger in a downstream direction through the agricultural and urban *** study area was an impaired coldwater stream in Michigan,***:Many factors structured the biological communities along the agricultural-to-urban land use *** woody debris had the strongest relationship with EPT(Ephemeroptera,Plecoptera,and Trichoptera)abundance and richness and were most common in the lower,urbanized *** streambed substrate had the strongest relationship with diptera taxa and surface air breather macroinvertebrates and was dominant in agricultural *** community assemblage was influenced largely by stream flow and temperature regimes,while poor fish community integrity in lower urban reaches could be impacted by geomorphology and episodic urban pollution *** macroinvertebrates were most abundant in deforested,first-order agricultural headwaters,while EPT macroinvertebrate richness was the highest downstream of agricultural areas within the urban zone that had extensive forest ***:Environmental variables and aquatic communities would often not conform with what we would expect from an idealized natural *** richness improved downstream of agricultural *** shows promise for the recovery of aquatic systems using we

关键词： Land use Habitat Stream Fish Macroinvertebrate Gradient

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Effects of a regenerating matrix on the survival of birds in tropical forest fragments

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Avian Research 2020年第1期11卷 16-24页

作者： Jared d.Wolfe Philip C.Stouffer richard O.Bierregaard Jr david A.Luther Thomas E.Lovejoy College of Forest Resources and Environmental Science Michigan Technological UniversityHoughtonMI 49931USA Biological dynamics of Forest Fragments Project Instituto Nacional de Pesquisas da AmazoiaManaus 69011Brazil College of Renewable Natural Resources Louisiana State University AgCenterLouisiana State UniversityBaton RougeLA 70803USA Biology department George Mason University4400 University Drive MS3EFairfaxVA 22030USA

Background: Vast areas of lowland neotropical forest have regenerated after initially being cleared for agricultural purposes. The ecological value of regenerating second growth to forest-dwelling birds may largely depend on the age of the forest, associated vegetative structure, and when it is capable of sustaining avian demographics similar to those found in pristine ***: To determine the influence of second growth age on bird demography, we estimated the annual survival of six central Amazonian bird species residing in pristine forest, a single 100 and a single 10 ha forest fragment, taking into consideration age of the surrounding matrix(i.e. regenerating forest adjacent to each fragment) as an explanatory ***: Study species exhibited three responses: arboreal, flocking and ant-following insectivores(Willisornis poecilinotus, Thamnomanes ardesiacus and Pithys albifrons) showed declines in survival associated with fragmentation followed by an increase in survival after 5 years of matrix regeneration. Conversely, Percnostola rufifrons, a gap-specialist, showed elevated survival in response to fragmentation followed by a decline after 5 years of regeneration. Lastly, facultative flocking and frugivore species(Glyphorynchus spirurus and dixiphia pipra, respectively) showed no response to adjacent clearing and subsequent ***: Our results in association with previous studies confirm that the value of regenerating forest surrounding habitat patches is dependent on two factors: ecological guild of the species in question and second growth age. Given the rapid increase in survival following succession, we suggest that the ecological value of young tropical forest should not be based solely on a contemporary snapshot, but rather, on the future value of mature second growth as well.

关键词： Amazon fragmentation Brazil Matrix Second growth Survival Tropical bird

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Zircon within chromitite requires revision of the tectonic history of the Eoarchean Itsaq Gneiss complex,Greenland

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Geoscience Frontiers 2023年第6期14卷 273-285页

作者： Hikaru Sawada Tomoaki Morishita Adrien Vezinet richard Stern Kenichiro Tani Ikuya Nishio Kanta Takahashi d.Graham Pearson Kristoffer Szilas department of Earth System Science University of ToyamaToyamaJapan X-Star Japan Agency for Marine-Earth Science and Technology(JAMSTEC)KanagawaJapan Faculty of Geosciences and Civil Engineering Kanazawa UniversityKanazawaJapan Lamont-doherty Earth Observatory Columbia UniversityPalisadesUSA Volcanoes and Earth’s Interior Research Center JAMSTECKanagawaJapan department of Earth and Atmospheric Sciences University of AlbertaEdmontonCanada Canadian Centre for Isotopic Microanalysis University of AlbertaEdmontonCanada National Museum of Nature and Science TsukubaJapan department of Geosciences and Natural Resource Management University of CopenhagenCopenhagenDenmark

The Ujaragssuit Nunat layered(UNL)unit in the Itsaq Gneiss Complex,west Greenland,has been consid-ered to contain one of the oldest chromitites on Earth based on~ca.4.1 Ga Hadean whole rock Pt-Os model ages and ca.3.81 Ga zircon U-Pb age of the surrounding *** study obtained zircon from the chromitite within this unit as well as granitoid sheets that intruded into the UNL ***-situ U-Pb-Hf-O isotope measurements were made on the *** from both the chromitite and the intrusive granitoids show concordant U-Pb ages of ca.2.97-2.95 *** contrast,Hf and 0 isotopic anal-yses indicate that zircons in the chromitites have a different origin from those in the intrusive *** from granitoids yielded Th/U ratios higher than 0.2,initial Hf isotope ratios of 0.2805-0.2807(i.e,initial:Hf value of-11 to-5),andδ^(18)O values of mostly 6.0‰-7.0‰,which are typical for felsic igneous rocks in Archean continental *** least altered zircons from a chromitite exhibited initial Hf isotope ratios of 0.28078-0.28084(i.e.,initial:Hf value of-1.1 to-0.4),close the chondritic value at ca.3.0 Ga and the depleted mantle at ca.3.2 *** zircons also haveδ^(18)O values of 4.2‰6.1‰which correspond to typical mantle *** other chromitite zircons yielded Th/U ratios lower than 0.1,and Hf and 0 isotopic compositions ranging between the least altered zircons and the intrusive granitoid *** results indicate that the zircons in the chromitites crystallized before or during the 2.97-2.95 Ga granitoid intrusion and most of the zircons were altered by subsequent ***,the present results suggest that zircons in the chromitites originally had depleted Hf iso-topic compositions at ca.3.2-3.0 *** can be explained by two different models of the evolution of the UNL *** is that if the UNL unit was formed at>3.81 Ga as previously thought,with the zircons in the chromitites subsequently being precipitated by ca.3.2-2.95 G

关键词： Archean Itsaq gneiss complex Ultramafic rock Metasomatism

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Paleomagnetic, tectonic and geochronological constraints for Permian-Triassic oroclinal bending of the Mongolian collage

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National Science Review 2023年第2期10卷 9-11页

作者： Karel Schulmann Jean Bernard Edel Ondrej Lexa Wenjiao Xiao d.T■ebínová richard Spikings Urs Schaltegger Arkadiusz derkowski Marek Szczerba Centre for Lithospheric Research Czech Geological Survey Institut Terre et Environnement de Strasbourg Université de Strasbourg Institute of Petrology and Structural Geology Charles University Xinjiang Research Center for Mineral Resources Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Earth and Environmental Sciences Department of Earth Sciences University of Geneva Institute of Geological Sciences Polish Academy of Sciences

The Central Asian Orogenic Belt constitutes the Kazakhstan and Mongolian oroclinal collages located between the Tarim-North China collage(TNC)to the south and the Siberian craton to the north(Fig.1a) [1].While the oroclinal bending of the western Kazakhstan collage is widely accepted by the paleomagnetic and tectonic community,the oroclinal bending model of the eastern Mongolian collage is disputed[2,3].despite differences,

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Chemo-dynamical modelling with Schwarzschild's method

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Research in Astronomy and Astrophysics 2018年第12期18卷 1-8页

作者： richard John Long Shude Mao National Astronomical Observatories Chinese Academy of Sciences Jodrell Bank Centre for Astrophysics School of Physics and Astronomy The University of Manchester Physics department and Tsinghua Centre for Astrophysics Tsinghua University

We extend Schwarzschild’s dynamical modelling method to model absorption line strength data as well as the more usual luminosity and kinematic *** approach draws on earlier published work by the first author with the Syer & Tremaine made-to-measure(M2M) dynamical modelling method and uses similar ideas to create a chemo-Schwarzschild *** apply our extended Schwarzschild method to the same four early type galaxies(NGC 1248, NGC 3838, NGC 4452,NGC 4551) as the chemo-M2M work, and are able to recover successfully the 2d absorption line strength for the three lines we model(Hβ, Fe5015, Mg b).We believe that this is the first time Schwarzschild’s method has been used in this *** techniques developed can be applied to modelling other aspects of galaxies, for example age and metallicity data coming from stellar population modelling, and are not specific to absorption line strength data.

关键词： galaxies:abundances galaxies:formation galaxies:individual(NGC 1248,NGC 3838,NGC 4452,NGC 4551) galaxies:kinematics and dynamics galaxies:structure methods:numerical

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