194 research outputs found
Building equitable literate futures : home and school computer-mediated literacy practices and disadvantage
This paper examines the complex connections between literacy practices, the use of information and communication technologies (ICTs) and disadvantage. It reports the findings of a year-long study which investigated the ways in which four families use ICTs to engage with formal and informal literacy learning in home and school settings. The research set out to explore what it is about computer-mediated literacy practices at home and at school in disadvantaged communities that make a difference in school success. The findings demonstrate that the \u27socialisation\u27 of the technology - its appropriation into existing family norms, values and lifestyles - varied from family to family. Having access to ICTs at home was not sufficient for the young people and their families to overcome the so-called \u27digital divide\u27. Clearly, we are seeing shifts in the meaning of \u27disadvantage\u27 in a globalised world mediated by the use of new technologies. New definitions of disadvantage that take account not only of access to the new technologies but also include calibrated understandings of what constitutes the access are required. The article concludes that old inequalities have not disappeared, but are playing out in new ways in the context of the networked society.<br /
They\u27re the future and they\u27re going to take over everywhere : ICTs, literacy and disadvantage
Structural diversification of the aminobicyclo[4.3.0]nonane skeleton using alkynylsilyl-derived allylic trichloroacetimidates
The amino substituted bicyclo[4.3.0]nonane is a molecular scaffold found in a wide range of natural products and medicinal agents. Despite this, synthetic methods for the general preparation of this structural motif are sparse. Here we evaluate a diastereoselective approach for the preparation of vinylsilyl derived aminobicyclo[4.3.0]nonanes using a one-pot multi-bond forming process involving a Pd(II)-catalysed Overman rearrangement, a Ru(II)-catalysed ring closing enyne metathesis reaction, followed by a hydrogen bonding directed Diels-Alder reaction. We show that a benzyldimethylsilyl-substituted alkene analogue is amenable to further functionalisation and the late stage generation of diverse sp3-rich, drug-like aminobicyclo[4.3.0]nonane scaffolds with up to six stereogenic centres
The UTMOST pulsar timing programme II:Timing noise across the pulsar population
While pulsars possess exceptional rotational stability, large scale timing
studies have revealed at least two distinct types of irregularities in their
rotation: red timing noise and glitches. Using modern Bayesian techniques, we
investigated the timing noise properties of 300 bright southern-sky radio
pulsars that have been observed over 1.0-4.8 years by the upgraded Molonglo
Observatory Synthesis Telescope (MOST). We reanalysed the spin and spin-down
changes associated with nine previously reported pulsar glitches, report the
discovery of three new glitches and four unusual glitch-like events in the
rotational evolution of PSR J18250935. We develop a refined Bayesian
framework for determining how red noise strength scales with pulsar spin
frequency () and spin-down frequency (), which we apply to a
sample of 280 non-recycled pulsars. With this new method and a simple power-law
scaling relation, we show that red noise strength scales across the
non-recycled pulsar population as , where and . This method can be
easily adapted to utilise more complex, astrophysically motivated red noise
models. Lastly, we highlight our timing of the double neutron star PSR
J07373039, and the rediscovery of a bright radio pulsar originally found
during the first Molonglo pulsar surveys with an incorrectly catalogued
position.Comment: Accepted by MNRAS. 28 pages, 8 figures, 8 table
Effect of thong style flip-flops on children’s barefoot walking and jogging kinematics
BACKGROUND: Thong style flip-flops are a popular form of footwear for children. Health professionals relate the wearing of thongs to foot pathology and deformity despite the lack of quantitative evidence to support or refute the benefits or disadvantages of children wearing thongs. The purpose of this study was to compare the effect of thong footwear on children’s barefoot three dimensional foot kinematics during walking and jogging. METHODS: Thirteen healthy children (age 10.3 ± 1.6 SD years) were recruited from the metropolitan area of Sydney Australia following a national press release. Kinematic data were recorded at 200 Hz using a 14 camera motion analysis system (Cortex, Motion Analysis Corporation, Santa Rosa, USA) and simultaneous ground reaction force were measured using a force platform (Model 9281B, Kistler, Winterthur, Switzerland). A three-segment foot model was used to describe three dimensional ankle, midfoot and one dimensional hallux kinematics during the stance sub-phases of contact, midstance and propulsion. RESULTS: Thongs resulted in increased ankle dorsiflexion during contact (by 10.9°, p; = 0.005 walk and by 8.1°, p; = 0.005 jog); increased midfoot plantarflexion during midstance (by 5.0°, p; = 0.037 jog) and propulsion (by 6.7°, p; = 0.044 walk and by 5.4°, p;= 0.020 jog); increased midfoot inversion during contact (by 3.8°, p;= 0.042 jog) and reduced hallux dorsiflexion during walking 10% prior to heel strike (by 6.5°, p; = 0.005) at heel strike (by 4.9°, p; = 0.031) and 10% post toe-off (by 10.7°, p; = 0.001). CONCLUSIONS: Ankle dorsiflexion during the contact phase of walking and jogging, combined with reduced hallux dorsiflexion during walking, suggests a mechanism to retain the thong during weight acceptance. Greater midfoot plantarflexion throughout midstance while walking and throughout midstance and propulsion while jogging may indicate a gripping action to sustain the thong during stance. While these compensations exist, the overall findings suggest that foot motion whilst wearing thongs may be more replicable of barefoot motion than originally thought
Probing the quality control mechanism of theEscherichia colitwin-arginine translocase with folding variants of ade novo-designed heme protein
Protein transport across the cytoplasmic membrane of bacterial cells is mediated by either the general secretion (Sec) system or the twin arginine translocase (Tat). The Tat machinery exports folded and cofactor containing proteins from the cytoplasm to the periplasm by using the transmembrane proton motive force as a source of energy. The Tat apparatus apparently senses the folded state of its protein substrates, a quality control mechanism that prevents premature export of nascent unfolded or misfolded polypeptides, but its mechanistic basis has not yet been determined. Here, we investigated the innate ability of the model Escherichia coli Tat system to recognize and translocate de novo-designed protein substrates with experimentally determined differences in the extent of folding. Water-soluble, four-helix bundle maquette proteins were engineered to bind two, one or no heme b cofactors, resulting in a concomitant reduction in the extent of their folding, assessed with temperature-dependent CD spectroscopy and one-dimensional 1H NMR spectroscopy. Fusion of the archetypal N-terminal Tat signal peptide of the E. coli trimethylamine-N-oxide (TMAO) reductase (TorA) to the N-terminus of the protein maquettes was sufficient for the Tat system to recognize them as substrates. The clear correlation between the level of Tat-dependent export and the degree of heme b-induced folding of the maquette protein suggested that the membrane-bound Tat machinery can sense the extent of folding and conformational flexibility of its substrates. We propose that these artificial proteins are ideal substrates for future investigations of the Tat system’s quality control mechanism
Self-defining Memories, Scripts, and the Life Story: Narrative Identity in Personality and Psychotherapy
An integrative model of narrative identity builds on a dual memory system that draws on episodic memory and a long-term self to generate autobiographical memories. Autobiographical memories related to critical goals in a lifetime period lead to life-story memories, which in turn become self-defining memories when linked to an individual\u27s enduring concerns. Self-defining memories that share repetitive emotion-outcome sequences yield narrative scripts, abstracted templates that filter cognitive-affective processing. The life story is the individual\u27s overarching narrative that provides unity and purpose over the life course. Healthy narrative identity combines memory specificity with adaptive meaning-making to achieve insight and well-being, as demonstrated through a literature review of personality and clinical research, as well as new findings from our own research program. A clinical case study drawing on this narrative identity model is also presented with implications for treatment and research
GAMA/G10-COSMOS/3D-HST: The 0<z<5 cosmic star-formation history, stellar- and dust-mass densities
We use the energy-balance code MAGPHYS to determine stellar and dust masses, and dust corrected star-formation rates for over 200,000 GAMA galaxies, 170,000 G10-COSMOS galaxies and 200,000 3D-HST galaxies. Our values agree well with previously reported measurements and constitute a representative and homogeneous dataset spanning a broad range in stellar mass (10^8---10^12 Msol), dust mass (10^6---10^9 Msol), and star-formation rates (0.01---100 Msol per yr), and over a broad redshift range (0.0 < z < 5.0). We combine these data to measure the cosmic star-formation history (CSFH), the stellar-mass density (SMD), and the dust-mass density (DMD) over a 12 Gyr timeline. The data mostly agree with previous estimates, where they exist, and provide a quasi-homogeneous dataset using consistent mass and star-formation estimators with consistent underlying assumptions over the full time range. As a consequence our formal errors are significantly reduced when compared to the historic literature. Integrating our cosmic star-formation history we precisely reproduce the stellar-mass density with an ISM replenishment factor of 0.50 +/- 0.07, consistent with our choice of Chabrier IMF plus some modest amount of stripped stellar mass. Exploring the cosmic dust density evolution, we find a gradual increase in dust density with lookback time. We build a simple phenomenological model from the CSFH to account for the dust mass evolution, and infer two key conclusions: (1) For every unit of stellar mass which is formed 0.0065---0.004 units of dust mass is also formed; (2) Over the history of the Universe approximately 90 to 95 per cent of all dust formed has been destroyed and/or ejected
- …