25 research outputs found

    Australian-derived detrital zircons in the Permian-Triassic Gympie terrane (eastern Australia): evidence for an autochthonous origin

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    The Tasmanides in eastern Australia record accretionary processes along the eastern Gondwana margin during the Phanerozoic. The Gympie terrane is the easternmost segment of the Tasmanides, but whether its origin was autochthonous or allochthonous is a matter of debate. We present U-Pb ages of detrital zircons from Permian and Triassic sedimentary rocks of the Gympie terrane with the aim of tracing the source of the sediments and constraining their tectonic relationships with the Tasmanides. Our results show that the Permian stratigraphic units from the Gympie terrane mainly contain Carboniferous and Permian detrital zircons with dominant age peaks at ~263 Ma, ~300 Ma, ~310 Ma, and ~330 Ma. The provenance ages of the Triassic sedimentary units are similar (~256 Ma, ~295 Ma, and ~328 Ma) with an additional younger age peak of ~240 Ma. This pattern of provenance ages from the Gympie terrane is correlative to episodes of magmatism in the adjacent component of the Tasmanides (New England Orogen), indicating that the detrital zircons were dominantly derived from the Australian continent. Given the widespread input of detrital zircons from the Tasmanides, we think that the sedimentary sequence of the Gympie terrane was deposited along the margin of the eastern Australian continent, possibly in association with a Permo-Triassic continental arc system. Our results do not show evidence for an exotic origin of the Gympie terrane, indicating that similarly to the vast majority of the Tasmanides, the Gympie terrane was genetically linked to the Australian continent

    Episodic behavior of Gondwanide deformation in eastern Australia: Insights from the Gympie Terrane

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    The mechanisms that drove Permian-Triassic orogenesis in Australia and throughout the Cordilleran-type Gondwanan margin is a subject of debate. Here we present field-based results on the structural evolution of the Gympie Terrane (eastern Australia), with the aim of evaluating its possible role in triggering widespread orogenesis. We document several deformation events (D–D) in the Gympie Terrane and show that the earliest deformation, D, occurred only during the final pulse of orogenesis (235–230\ua0Ma) within the broader Gondwanide Orogeny. In addition, we found no evidence for a crustal suture, suggesting that terrane accretion was not the main mechanism behind deformation. Rather, the similar spatiotemporal evolution of Permian-Triassic orogenic belts in Australia, Antarctica, South Africa, and South America suggest that the Gondwanide Orogeny was more likely linked to large-scale tectonic processes such as plate reorganization. In the context of previous work, our results highlight a number of spatial and temporal variations in pulses of deformation in eastern Australia, suggesting that shorter cycles of deformation occurred at a regional scale within the broader episode of the Gondwanide Orogeny. Similarly to the Cenozoic evolution of the central and southern Andes, we suggest that plate coupling and orogenic cycles in the Late Paleozoic to Early Mesozoic Gondwanide Orogeny have resulted from the superposition of mechanisms acting at a range of scales, perhaps contributing to the observed variations in the intensity, timing, and duration of deformation phases within the orogenic belt

    Formal nursing terminology systems: a means to an end

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    In response to the need to support diverse and complex information requirements, nursing has developed a number of different terminology systems. The two main kinds of systems that have emerged are enumerative systems and combinatorial systems, although some systems have characteristics of both approaches. Differences in the structure and content of terminology systems, while useful at a local level, prevent effective wider communication, information sharing, integration of record systems, and comparison of nursing elements of healthcare information at a more global level. Formal nursing terminology systems present an alternative approach. This paper describes a number of recent initiatives and explains how these emerging approaches may help to augment existing nursing terminology systems and overcome their limitations through mediation. The development of formal nursing terminology systems is not an end in itself and there remains a great deal of work to be done before success can be claimed. This paper presents an overview of the key issues outstanding and provides recommendations for a way forward

    eLearning techniques supporting problem based learning in clinical simulation

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    This paper details the results of the first phase of a project using eLearning to support students’ learning within a simulated environment. The locus was a purpose built clinical simulation laboratory (CSL) where the School\u27s philosophy of problem based learning (PBL) was challenged through lecturers using traditional teaching methods. The solution: a student-centred, problem based approach to the acquisition of clinical skills that used high quality learning objects embedded within web pages, substituting for lecturers providing instruction and demonstration. This encouraged student nurses to explore, analyse and make decisions within the safety of a clinical simulation. Learning was facilitated through network communications and reflection on video performances of self and others. Evaluations were positive, students demonstrating increased satisfaction with PBL, improved performance in exams, and increased self-efficacy in the performance of nursing activities. These results indicate that eLearning techniques can help students acquire clinical skills in the safety of a simulated environment within the context of a problem based learning curriculum

    The Onset of Gondwanide Orogeny in Eastern Australia: Insight From the Provenance of Syn-Orogenic Strata in the New England Orogen (Australia)

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    The last major episode of cordilleran-style tectonism in eastern Australia was the late Paleozoic-early Mesozoic Gondwanide Orogeny. When exactly this deformation commenced and what caused this phase of orogenesis is still debated. Using previous stratigraphic and sedimentological data from pre-orogenic to syn-orogenic strata, integrated with new detrital zircon U-Pb geochronology, we investigated the onset of the Gondwanide Orogeny in the northern New England Orogen (Gogango Overfolded Zone, eastern Australia). The lowermost syn-orogenic strata display evidence of rapid base-level change coeval with increasingly abundant and more proximal mass-wasting deposits, which reflect a shift to static loading-induced subsidence and the establishment of a ∼1,600-km long foreland basin system. The syn-orogenic strata contain abundant detritus sourced from syn-depositional magmatism, alongside an up-section increase in detritus derived from uplifted older rocks of the New England Orogen. Detrital zircons show maximum depositional age of ∼276 Ma from immediately above the sequence boundary, and ∼269 Ma from an overlying formation. These results confirm previous suggestions that tectonic forcing of the orogenic hinterland affected subsidence and sedimentation patterns in the easternmost part of the basin during the middle Permian, >11 Myr prior to deformation in the western part of the foreland basin. The onset of the Gondwanide Orogeny in eastern Australia, and in other sectors of the Gondwanan margin, likely resulted from a tectonic switch from crustal extension to contraction, which was driven by increased convergence rates due to a plate reorganization event following the final assembly of Pangea.</p

    Extending julius seizure, a bang-sensitive gene, as a model for studying epileptogenesis: Cold shock, and a new insertional mutation

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    The bang-sensitive (BS) mutants of Drosophila are an important model for studying epilepsy. We recently identified a novel BS locus, julius seizure (jus), encoding a protein containing two transmembrane domains and an extracellular cysteine-rich loop. We also determined that jussda iso7.8, a previously identified BS mutation, is an allele of jus by recombination, deficiency mapping, complementation testing, and genetic rescue. RNAi knockdown revealed that jus expression is important in cholinergic neurons and that the critical stage of jus expression is the mid-pupa. Finally, we found that a functional, GFP-tagged genomic construct of jus is expressed mostly in axons of the neck connectives and of the thoracic abdominal ganglia. In this Extra View article, we show that a MiMiC GFP-tagged Jus is localized to the same nervous system regions as the GFP-tagged genomic construct, but its expression is mostly confined to cell bodies and it causes bang-sensitivity. The MiMiC GFP-tag lies in the extracellular loop while the genomic construct is tagged at the C-terminus. This suggests that the alternate position of the GFP tag may disrupt Jus protein function by altering its subcellular localization and/or stability. We also show that a small subset of jus-expressing neurons are responsible for the BS phenotype. Finally, extending the utility of the BS seizure model, we show that jus mutants exhibit cold-sensitive paralysis and are partially sensitive to strobe-induced seizures

    EUNIS habitat classification and associated confidence shapefiles for Atlantic regions investigated by the EU H2020 project iAtlantic (Version 1)

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    This dataset includes 11 regional EUNIS-classified habitat maps (100-1000 km) and associated confidence maps that were created as a project milestone (Nr. 12) of the EU H2020 project 'iAtlantic'. The 12 iAtlantic regions encompass 1. Subpolar Mid-Atlantic Ridge, off Iceland MFRI, 2. Rockall Trough to PAP, 3. Central mid-Atlantic Ridge, 4. NW Atlantic, Gully Canyon, 5. Sargasso Sea, 6. Eastern Tropical North Atlantic, Cape Verde, 7. Equatorial Atlantic, Romanche Fracture Zone, 8. Slope & margin off Angola & Congo Lobe, 9. Benguela Current, Walvis Ridge to South Africa, 10. Brazil margin & Santos and Campos Basin, 11. Vitória-Trindade Seamount Chain and 12. Malvinas Current. For each of the regions 2-12, a shapefile of polygons classified according to the 2022 EUNIS classification level 3 and a second shapefile of the same polygons attributed with their confidence level according to the MESH Accuracy & Confidence Working approach was created. EUNIS classifications combined biozone and substrate data. Biozones were assigned from bathymetry. Where MBES was not available, GEBCO bathymetry was used. Substrate data were extracted from pre-existing geological/substrate mapping efforts and converted to EUNIS classifications via cross walks or, where substrate data were limited, substrate layers were modelled using Random Forest. No additional information to that used in the EUSeaMap was available for region 1. Therefore, shapefiles were not created for region 1

    EUNIS habitat classification and associated confidence shapefiles for Atlantic regions investigated by the EU H2020 project iAtlantic (Version 2)

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    This dataset includes 11 regional EUNIS-classified habitat maps (100-1000 km) and associated confidence maps that were created as a project milestone (Nr. 12) of the EU H2020 project 'iAtlantic'. The 12 iAtlantic regions encompass 1. Subpolar Mid-Atlantic Ridge, off Iceland MFRI, 2. Rockall Trough to PAP, 3. Central mid-Atlantic Ridge, 4. NW Atlantic, Gully Canyon, 5. Sargasso Sea, 6. Eastern Tropical North Atlantic, Cape Verde, 7. Equatorial Atlantic, Romanche Fracture Zone, 8. Slope & margin off Angola & Congo Lobe, 9. Benguela Current, Walvis Ridge to South Africa, 10. Brazil margin & Santos and Campos Basin, 11. Vitória-Trindade Seamount Chain and 12. Malvinas Current. For each of the regions 2-12, a shapefile of polygons classified according to the 2022 EUNIS classification level 3 and a second shapefile of the same polygons attributed with their confidence level according to the MESH Accuracy & Confidence Working approach was created. EUNIS classifications combined biozone and substrate data. Biozones were assigned from bathymetry. Where MBES was not available, GEBCO bathymetry was used. Substrate data were extracted from pre-existing geological/substrate mapping efforts and converted to EUNIS classifications via cross walks or, where substrate data were limited, substrate layers were modelled using Random Forest. The EUNIS habitat map for Region 4 was based on the pre-existing surficial geology compilation of the Scotian Shelf bioregion compiled by the Geological Survey of Canada. The EUNIS habitat map for Region 9 was based on the pre-existing South African habitat map that uses a modified IUCN hierarchical classification system. No additional information to that used in the EUSeaMap was available for Region 1. Therefore, shapefiles were not created for Region 1
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