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Tectonic drivers and the influence of the Kerguelen plume on seafloor spreading during formation of the early Indian Ocean
No full textThe Perth Abyssal Plain (PAP), located offshore southwest Australia, formed at the centre of Mesozoic East Gondwana breakup and Kerguelen plume activity. Despite its importance as a direct and relatively undisturbed recorder of this early spreading history, sparse geophysical data sets and lack of geological sampling hamper our understanding of the evolution of the PAP. This study combines new bathymetric profiles across the PAP with petrographic and geochemical data from the first samples ever to be dredged from the flanks of the Dirck Hartog Ridge (DHR), a prominent linear bathymetric feature in the central PAP, to better constrain the formation of the early Indian Ocean floor and the influence of the Kerguelen plume. Seafloor spreading in the PAP initiated at ~136 Ma with spreading observed to occur at (half) rates of ~35 mm/yr. Changes in spreading rate are difficult to discern after the onset of the Cretaceous Quiet Zone at ~120 Ma, but an increase in seafloor roughness towards the centre of the PAP likely resulted from a half-spreading rate decrease from 35 mm/yr (based on magnetic reversals) to ~24 mm/yr at ~114 Ma. Exhumed gabbro dredged from the southernmost dredge site of the DHR supports a further slowdown of spreading immediately prior to full cessation at ~102 Ma. The DHR exhibits a high relief ridge axis and distinctive asymmetry that is unusual compared to most active or extinct spreading centres. The composition of mafic volcanic samples varies along the DHR, from sub-alkaline dolerites with incompatible element concentrations most similar to depleted-to-normal mid-ocean ridge basalts in the south, to alkali basalts similar to ocean island basalts in the north. Therefore, magma sources and degrees of partial melting varied in space and time. It is likely that the alkali basalts are a manifestation of later excess volcanism, subsequent to or during the cessation of spreading. In this case, enriched signatures may be attributed tectonic drivers and melting of a heterogeneous mantle, or to an episodic influence of the Kerguelen plume over distances greater than 1000 km. We also investigate possible scenarios to explain how lower crustal rocks were emplaced at the crest of the southern DHR. Our results demonstrate the significance of regional tectonic plate motions on the formation and deformation of young ocean crust, and provide insight into the unique DHR morphology.18 page(s
A Novel malware for subversion of self-protection in anti-virus
No full textMajor anti-virus solutions have introduced a feature known as ‘self-protection’ so that malware (and even users) cannot modify or disable the core functionality of their products. In this paper, we have investigated 12 anti-virus products from four vendors (AVG, Avira, McAfee and Symantec) and have discovered that they have certain security weaknesses that can be exploited by malware. We have then designed a novel malware, which makes use of the weaknesses in anti-virus software and embeds itself to become a part of the vulnerable anti-virus solution. It subverts the self-protection features of several anti-virus software solutions. This malware integrated anti-virus enjoys several advantages such as longevity (anti-virus is active while the system is running), improved stealthy behaviour, highest privilege and capability to bypass security measures. Then we propose an effective defence against such malware. We have also implemented the defensive measure and evaluated its effectiveness. Finally, we show how the proposed defence can be applied to the current versions of vulnerable anti-virus solutions without requiring signficant modifications.19 page(s
The Construction of P.Bodmer VIII and the Bodmer "composite" or "miscellaneous" codex
No full textThe construction of the so-called Bodmer Composite or Miscellaneous codex has been an ongoing problem since the publication of its constituent parts began in the 1950s. A recent inspection of high resolution digital images of P.Bodmer VIII shows compellingly that this portion of the codex had more than one phase of use, was originally part of a separate codex, and was only later removed and joined to the other sections of the Bodmer "composite" codex. The New Testament manuscript known as P72 (P.Bodmer VII + P.Bodmer VIII) is thus a codicological unity only in a secondary sense.17 page(s
Location-based effects underlie feature conjunction benefits in visual working memory
No full textStudies of visual working memory (VWM) have reported that different features belonging to the same object (conjunctions) are better retained than the same features belonging to spatially separated objects (disjunctions). This conjunction benefit has been taken as evidence for the theory that VWM representations are object-based. However, compared to separate features, conjunctions also occupy fewer locations. Here we tested the alternative hypothesis that the conjunction benefit reflects a spatial-based rather than an object-based advantage. Experiment 1 shows a clear VWM conjunction benefit for spatially laid out displays of memory items. However, when the same items were presented sequentially at one location (i.e., location was noninformative), memory performance was equivalent for conjunction and disjunction conditions. Experiment 2 shows that only when the probe carries spatial information (i.e., it matches the location of the memory item) does a conjunction benefit occur. Taken together, these results put important boundaries on object-based theories of VWM.13 page(s
A Study into the legislative - and related key policy and operational - frameworks for sharing information relating to child sexual abuse in institutional contexts
No full textReport commissioned by the Royal Commission into Institutional Responses to Child Sexual Abuse examining law and policy across all Australian states and territories in order to identify elements that support appropriate and timely information sharing about children at risk and potential perpetrators and elements that potentially impede that information flow. The study considers in detail the relevant law and policy in those contexts in which children are most vulnerable: child protection; out-of-home-care; early childhood services; schools; juvenile justice; and extracurricular activities
Medium term effects of including manual therapy in a pulmonary rehabilitation program for chronic obstructive pulmonary disease (COPD) : a randomized controlled pilot trial
No full textStudy design: Randomized clinical trial. Objective: To investigate the effect of including manual therapy (MT) in a pulmonary rehabilitation program for patients with chronic obstructive pulmonary disease (COPD). Background: The primary source of exercise limitation in people with COPD is dyspnea. The dyspnea is partly caused by changes in chest wall mechanics, with an increase in chest wall rigidity (CWR) contributing to a decrease in lung function. As MT is known to increase joint mobility, administering MT to people with COPD carries with it the potential to influence CWR and lung function. Methods: Thirty-three participants with COPD, aged between 55 and 70 years (mean = 65·5±4 years), were randomly assigned to three groups: pulmonary rehabilitation (PR) only, soft tissue therapy (ST) and PR, and ST, spinal manipulative therapy (SM), and PR. Outcome measures including forced expiratory volume in the 1st second (FEV1), forced vital capacity (FVC), 6-minute walking test (6MWT), St. George's respiratory questionnaire (SGRQ), and the hospital anxiety and depression (HAD) scale were recorded at 0, 8, 16, and 24 weeks. Results: There was a significant difference in FVC between the three groups at 24 weeks (P = 0·04). For the ST+SM+PR group versus PR only the increase was 0·40 l (CI: 0·02, 0·79; P = 0·03). No major or moderate adverse events (AE) were reported following the administration of 131 ST and 272 SM interventions. Discussion: The increase in FVC is a unique finding. Although the underlying mechanisms responsible for this outcome are not yet understood, the most likely explanation is the synergistic effect resulting from the combination of interventions. These results support the call for a larger clinical trial in the use of MT for COPD.10 page(s
"You are in the state of grace?" the absence of grace and semantic embranglement in Shakespeare's Troilus and Cressida
No full textFrom its opening, language, and in particular its dysfunction, is reflexively foregrounded in Shakespeare's Troilus and Cressida. While some critics have followed John Dryden's disparagement of the drama's language, this essay argues that the playwright knowingly constructed his play such that its linguistic disorder exhibits and embodies the endemic disorderliness and disintegration—cosmic, moral, interpersonal and subjective—that characterises its world. This interrelationship of language and ontological state can be elucidated by exploring the significance to it of the question that, by virtue of the Reformation, became an axis of early modern theology and its far-reaching upheavals—how one becomes an eternal recipient of the grace of God. Perhaps surprisingly, Troilus contains echoes of the sixteenth-century controversies over grace. After exploring the interrelationship of language and the doctrine of divine grace, this essay considers how the absence of this grace is implicated in the ostensible semantic embranglement engendered by Troilus’ language. The focus is upon the play's central scenes, and the perversion of the speech act of promise.21 page(s
The Toxicity of arsenic(III), chromium(VI) and zinc to groundwater copepods
No full textGroundwater ecosystems globally are threatened by anthropogenic contamination, yet there are few ecotoxicological data using obligate groundwater biota on which to base risk assessments. Copepods are found inhabiting aquifers of different geologies around the world and so are a useful taxon for use in ecotoxicological studies of groundwater. The aim of this study was to test the sensitivity of obligate groundwater copepods to metal contaminants (arsenic(III), chromium(VI) and zinc) in groundwater in static 96 h, 14 days and 28 days exposure tests. The copepods were variably sensitive to As, Cr and Zn, with Cr being the most toxic across all taxa. No taxon was consistently most sensitive and there was no apparent relationship between the hardness, pH and organic carbon concentration of the diluent water and the sensitivity of biota. As expected, toxicity increased with exposure period and we encourage the use of longer exposure periods in future toxicity tests with groundwater organisms to reflect the greater exposure periods likely to be associated with groundwater contamination.10 page(s
A Model inter-comparison study to examine limiting factors in modelling Australian tropical savannas
No full textThe savanna ecosystem is one of the most dominant and complex terrestrial biomes, deriving from a distinct vegetative surface comprised of co-dominant tree and grass populations. While these two vegetation types co-exist functionally, demographically they are not static but are dynamically changing in response to environmental forces such as annual fire events and rainfall variability. Modelling savanna environments with the current generation of terrestrial biosphere models (TBMs) has presented many problems, particularly describing fire frequency and intensity, phenology, leaf biochemistry of C3 and C4 photosynthesis vegetation, and root-water uptake. In order to better understand why TBMs perform so poorly in savannas, we conducted a model inter-comparison of six TBMs and assessed their performance at simulating latent energy (LE) and gross primary productivity (GPP) for five savanna sites along a rainfall gradient in northern Australia. Performance in predicting LE and GPP was measured using an empirical benchmarking system, which ranks models by their ability to utilise meteorological driving information to predict the fluxes. On average, the TBMs performed as well as a multi-linear regression of the fluxes against solar radiation, temperature and vapour pressure deficit but were outperformed by a more complicated nonlinear response model that also included the leaf area index (LAI). This identified that the TBMs are not fully utilising their input information effectively in determining savanna LE and GPP and highlights that savanna dynamics cannot be calibrated into models and that there are problems in underlying model processes. We identified key weaknesses in a model's ability to simulate savanna fluxes and their seasonal variation, related to the representation of vegetation by the models and root-water uptake. We underline these weaknesses in terms of three critical areas for development. First, prescribed tree-rooting depths must be deep enough, enabling the extraction of deep soil-water stores to maintain photosynthesis and transpiration during the dry season. Second, models must treat grasses as a co-dominant interface for water and carbon exchange rather than a secondary one to trees. Third, models need a dynamic representation of LAI that encompasses the dynamic phenology of savanna vegetation and its response to rainfall interannual variability. We believe that this study is the first to assess how well TBMs simulate savanna ecosystems and that these results will be used to improve the representation of savannas ecosystems in future global climate model studies.21 page(s