Institution
Macquarie University
Education•Sydney, New South Wales, Australia•
About: Macquarie University is a education organization based out in Sydney, New South Wales, Australia. It is known for research contribution in the topics: Population & Laser. The organization has 14075 authors who have published 47673 publications receiving 1416184 citations. The organization is also known as: Macquarie uni.
Topics: Population, Laser, Galaxy, Anxiety, Mantle (geology)
Papers published on a yearly basis
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01 Feb 2000TL;DR: In the absence of crystal plasticity, the only indication of strain may be an alignment of crystals as mentioned in this paper, which is consistent with rotation of crystals in a much weaker medium, namely a melt phase, at a stage when the magma has become viscous enough to preserve the alignment.
Abstract: Evidence of magmatic flow includes: (a) parallel to sub-parallel alignment of elongate euhedral crystals (e.g., of feldspar or hornblende) that are not internally deformed, (b) imbrication (‘tiling’) of elongate euhedral crystals that are not internally deformed, (c) insufficient solid-state strain in regions between aligned or imbricated crystals to accommodate phenocryst rotation, (d) elongation of microgranitoid enclaves without plastic deformation of the minerals, (e) magmatic flow foliations and elongate microgranitoid enclaves deflected around xenoliths, and (f) schlieren layering (if due to flow sorting) in the absence of plastic deformation of the minerals involved. These features are consistent with rotation of crystals in a much weaker medium, namely a melt phase, at a stage when the magma has become viscous enough to preserve the alignment. Evidence of solid-state flow includes: (a) internal deformation and recrystallization of grains, (b) recrystallized “tails,” (c) elongation of recrystallized aggregates (e.g. of quartz and mica), (d) grainsize reduction, (e) fine-grained folia anastomosing around less deformed relics, (f) microcline twinning, (g) myrmekite, (h) flame perthite, (i) boudinage of strong minerals, typically with recrystallized aggregates of weaker minerals (e.g. quartz and mica) between the boudins, (j) foliation passing through, rather than around enclaves, and (k) heterogeneous strain with local mylonitic zones. Several criteria suggest “submagmatic flow,” including recrystallized feldspar, inferred transitions from magmatic imbrication to solid-state S/C arrangements, evidence of c-slip in quartz, and especially evidence of migration of residual melt into lower-pressure sites. Recent experimental studies indicate that a change from grain-supported flow to suspension flow typically occurs in deforming magmas at melt contents of between 20% to 40%, and that large amounts of strain may accumulate in magmas without being recorded by the final fabric. At lower melt percentages, perhaps as low as a few percent, depending on the minerals and their shapes, strain may be accommodated by: (a) melt-assisted grain-boundary sliding, (b) contact-melting assisted grain-boundary migration, (c) strain partitioning into melt-rich zones, (d) intracrystalline plastic deformation (c-slip in quartz indicating plastic deformation at temperatures near the granite solidus), and (f) transfer of melt to sites of low mean stress. The only indication of strain in the absence of crystal plasticity may be an alignment of crystals. Moreover, magmatic flow microstructures may be destroyed by fracturing, crystal plasticity and recrystallization before the magma reaches its solidus. Many rocks show evidence of solid-state flow superimposed on magmatic flow. Evidence of magmatic flow is commonly preserved in deformed felsic metamorphic rocks: for example the alignment of rectangular K-feldspar megacrysts and of microgranitoid enclaves. However, absence of alignment does not preclude a magmatic origin for K-feldspar megacrysts in felsic gneisses, as magmatic flow may cease before the magma becomes viscous enough to preserve an alignment.
257 citations
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TL;DR: Analysis of articles published between 2013 and 2015 reveals important differences between the use of default parameters and the best model approach, especially in the total area identified as suitable for the assessed species and the specific areas that are identified by both modelling approaches.
Abstract: Environmental niche modeling (ENM) is commonly used to develop probabilistic maps of species distribution. Among available ENM techniques, MaxEnt has become one of the most popular tools for modeling species distribution, with hundreds of peer-reviewed articles published each year. MaxEnt's popularity is mainly due to the use of a graphical interface and automatic parameter configuration capabilities. However, recent studies have shown that using the default automatic configuration may not be always appropriate because it can produce non-optimal models; particularly when dealing with a small number of species presence points. Thus, the recommendation is to evaluate the best potential combination of parameters (feature classes and regularization multiplier) to select the most appropriate model. In this work we reviewed 244 articles published between 2013 and 2015 to assess whether researchers are following recommendations to avoid using the default parameter configuration when dealing with small sample sizes, or if they are using MaxEnt as a "black box tool." Our results show that in only 16% of analyzed articles authors evaluated best feature classes, in 6.9% evaluated best regularization multipliers, and in a meager 3.7% evaluated simultaneously both parameters before producing the definitive distribution model. We analyzed 20 articles to quantify the potential differences in resulting outputs when using software default parameters instead of the alternative best model. Results from our analysis reveal important differences between the use of default parameters and the best model approach, especially in the total area identified as suitable for the assessed species and the specific areas that are identified as suitable by both modelling approaches. These results are worrying, because publications are potentially reporting over-complex or over-simplistic models that can undermine the applicability of their results. Of particular importance are studies used to inform policy making. Therefore, researchers, practitioners, reviewers and editors need to be very judicious when dealing with MaxEnt, particularly when the modelling process is based on small sample sizes.
257 citations
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TL;DR: The results suggest that the initial increase, subsequent decrease, and final prolonged increase in extracellular dopamine levels in the NAc are selectively mediated by LDT‐elicited activation of nicotinic and glutamatergic receptors in the VTA, (ii) muscarinic M2 autoreceptors on LDT cell bodies, and (iii) mus carinic receptors inThe VTA.
Abstract: Cholinergic and glutamatergic neurons in the laterodorsal tegmentum (LDT) and neighbouring mesopontine nuclei are thought to influence mesolimbic dopaminergic neuronal activity involved in goal-directed behaviours. We measured the changes in dopamine oxidation current (corresponding with dopamine efflux) in the nucleus accumbens (NAc) in response to electrical stimulation of the LDT using in vivo chronoamperometry in urethane-anaesthetized rats. LDT stimulation (35 Hz pulse trains for 60 s, 1 s intertrain interval) evoked a three-component change in dopamine efflux in the NAc: (i) an initial stimulation time-locked increase in the dopamine signal above baseline, followed by (ii) an immediate decrease below baseline, and thereafter by (iii) a prolonged increase in the dopamine signal above baseline. Intra-VTA infusion of the nicotinic receptor antagonist mecamylamine (5 microg/0.5 microL) or the ionotropic glutamate receptor antagonist kynurenate (10 microg/microL) attenuated the first LDT-elicited component. The second suppressive component was abolished by intra-LDT infusions of either the nonselective or the M2-selective muscarinic receptor antagonists scopolamine (100 microg/microL) and methoctramine (50 microg/microL), respectively. In contrast, intra-VTA infusions of scopolamine (200 microg/microL) resulted in a selective attenuation of the third facilitatory component, whereas both second and third components were abolished by systemic injections of scopolamine (5 mg/kg). These results suggest that the initial increase, subsequent decrease, and final prolonged increase in extracellular dopamine levels in the NAc are selectively mediated by LDT-elicited activation of (i) nicotinic and glutamatergic receptors in the VTA, (ii) muscarinic M2 autoreceptors on LDT cell bodies, and (iii) muscarinic receptors in the VTA, respectively.
256 citations
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University of Washington1, Aberystwyth University2, British Antarctic Survey3, Victoria University of Wellington4, Ghent University5, Harvard University6, Louisiana State University7, University of Cologne8, Austrian Academy of Sciences9, Scott Polar Research Institute10, Stanford University11, Leipzig University12, Loughborough University13, Centre national de la recherche scientifique14, Australian Nuclear Science and Technology Organisation15, University of New South Wales16, Alfred Wegener Institute for Polar and Marine Research17, Macquarie University18, University of Maine19, University of Calgary20, Northumbria University21, University of Bergen22, Colgate University23, Indiana University – Purdue University Indianapolis24, University of Otago25, University of Bremen26, University of Sheffield27, Paul Scherrer Institute28, Lamont–Doherty Earth Observatory29, Geoscience Australia30, University of West London31, University of California, Santa Barbara32, Rice University33, University of Edinburgh34, Lund University35, Australian Antarctic Division36, University of Canberra37
TL;DR: In this paper, the authors present a series of timeslice maps for 20 ka, 15 ka, 10 ka and 5 ka, including grounding line position and ice sheet thickness changes, along with a clear assessment of levels of confidence.
256 citations
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TL;DR: In this article, an analysis of the global distribution of U/Pb ages of both subduction-related granitoids and of detrital zircons suggests that a widespread reduction in magmatic activity on Earth beginning about 2.45 Ga and lasting for 200-250 My.
256 citations
Authors
Showing all 14346 results
Name | H-index | Papers | Citations |
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Yang Yang | 171 | 2644 | 153049 |
Peter B. Reich | 159 | 790 | 110377 |
Nicholas J. Talley | 158 | 1571 | 90197 |
John R. Hodges | 149 | 812 | 82709 |
Thomas J. Smith | 140 | 1775 | 113919 |
Andrew G. Clark | 140 | 823 | 123333 |
Joss Bland-Hawthorn | 136 | 1114 | 77593 |
John F. Thompson | 132 | 1420 | 95894 |
Xin Wang | 121 | 1503 | 64930 |
William L. Griffin | 117 | 862 | 61494 |
Richard Shine | 115 | 1096 | 56544 |
Ian T. Paulsen | 112 | 354 | 69460 |
Jianjun Liu | 112 | 1040 | 71032 |
Douglas R. MacFarlane | 110 | 864 | 54236 |
Richard A. Bryant | 109 | 769 | 43971 |