Provenance of the Early Mesoproterozoic Radium Creek Group in the northern Mount Painter Inlier: Correlating isotopic signatures to inform tectonic reconstructions

New in situ zircon LA-ICPMS geochronologic and Hf-isotope data from the Radium Creek Group within the Mount Painter Inlier provide important temporal constraints on the Early Mesoproterozoic palaeogeography of eastern Proterozoic Australia. The entire Radium Creek Group was deposited in a single basin forming phase, and has a maximum depositional age of 1595. ±. 3.7. Ma. Detrital zircon from these metasedimentary rocks have U-Pb age populations at ca. 1595. Ma, 1660-1680. Ma, 1710-1780. Ma, ca. 1850. Ma and ca. 2500. Ma. These grains are characterised by isotopically diverse and evolved sources, and have crystallised within predominantly felsic igneous host-rocks. The relative age spectra and isotopic character has more similarity with the Gawler Craton than the Arunta Block, Curnamona Province or the Mount Isa Inlier. These observations suggest that the Mount Painter Province was adjacent to the Gawler Craton in the Early Mesoproterozoic. Our data supports a coherent South Australian Craton at ca. 1595. Ma and a contiguous continental mass that included the North and South Australian cratons. The Mount Painter Inlier occupied a complex plate tectonic setting in the overriding plate of two convergent margins. © 2014 Elsevier B.V

The source of A-type magmas in two contrasting settings: U–Pb, Lu–Hf and Re–Os isotopic constraints

The sources of post-orogenic A-type magmas from two distinct geodynamic settings are compared. The end of the ca. 514–480 Ma Delamerian Orogeny, southeastern South Australia, was marked by ~ 10 Myr of bimodal A-type magmatism, driven by convective removal of thickened lithosphere. Initial Os and Hf isotope ratios record a heterogeneous lithospheric mantle source, with some input from aesthenospheric mantle. Mafic parental melts fractionated to produce the granites. In contrast, initial Os isotope ratios of the A-type magmas that comprise the ca. 1598–1583 Ma Mesoproterozoic Gawler Felsic Large Igneous Province, central South Australia, record a dominant evolved lower crust component. However, initial Hf isotope ratios from these samples are depleted, indicating a mantle source for lithophile elements. This voluminous, bimodal magmatism lasted for ~ 15 Myr, and ended the Wartakan Orogeny. In both cases the homogenisation of chemical (rheological) heterogeneities, inherited from terrain amalgamation and orogenic thickening, strengthened the lithosphere. The contemporaneous fusion of heterogeneous mantle ± crust may represent a common, stabilising influence on the lithospheric column regardless of tectono-magmatic setting

Burning down the house: The time to ignition of an irradiated solid

The combustion of a wooden door irradiated with thermal energy is studied in this paper. The problem is relevant to the mechanism by which house fires propagate, for example. A novel method is presented for computing the time-dependent behaviour of the temperature, which is also a function of a spatial coordinate. A boundary-integral method is used to reduce the mathematical formulation of the problem to a coupled system of Volterra-type integral equations, combined with a nonlinear rate equation. An efficient numerical method is used to solve this system with great accuracy. The time to ignition is obtained from these numerical solutions, and we show that spatial effects can cause an ignition event to occur at lower values of the incident radiation than would be expected from the classical steady-state ignition diagram. This is expected to have important consequences in understanding fire spread in buildings

Geometry & topology : GT

Contains fulltext : 186588.pdf (publisher's version ) (Closed access)BACKGROUND: Several rating scales have been developed to measure quality of recovery after surgery and anaesthesia, but the most extensively used is the QoR-40, a 40-item questionnaire that provides a global score and subscores across five dimensions: patient support, comfort, emotions, physical independence, and pain. It has been evaluated in a variety of settings, but its overall psychometric properties (validity, reliability, ease of use, and interpretation) and clinical utility are uncertain. METHODS: We undertook a quantitative systematic review of studies evaluating psychometric properties of the QoR-40. Data were combined in meta-analyses using random effects models. This resulted in a total sample of 3459 patients from 17 studies originating in nine countries. RESULTS: We confirmed content, construct, and convergent [pooled r=0.58, 95% confidence interval (CI): 0.51-0.65] validity. Reliability was confirmed by excellent intraclass correlation (pooled alpha=0.91, 95% CI: 0.88-0.93), test-retest reliability (pooled r=0.90, 95% CI: 0.86-0.92), and inter-rater reliability (intraclass correlation=0.86). The clinical utility of the QoR-40 instrument was supported by high patient recruitment into evaluation studies (97%), and an excellent completion and return rate (97%). The mean time to complete the QoR-40 was 5.1 (95% CI: 4.4-5.7) min. CONCLUSIONS: The QoR-40 is a widely used and extensively validated measure of quality of recovery. The QoR-40 is a suitable measure of postoperative quality of recovery in a range of clinical and research situations