485 research outputs found
iPad Apps and Visual Methodologies: Empirical and ethical issues in achieving authentic data
This article suggests new ways of working with visual data collected with or via
iPads. Using the example of two iPad apps that we co-created, we argue that
multimedia and display recorder apps can generate highly authentic data, capable
of providing unique insights into the activities and experiences of young children
that more conventional data methods cannot achieve. We discuss and illustrate
how the use of the apps addresses some empirical and ethical challenges concerning
the positioning of the child and researcher in observational research, notably
in relation to observer effects and researcher subjectivity. We outline some principles
and strategies for researchers interested in using iPad apps and address some
challenges and use considerations of these innovative methods
Electron Transport through Disordered Domain Walls: Coherent and Incoherent Regimes
We study electron transport through a domain wall in a ferromagnetic nanowire
subject to spin-dependent scattering. A scattering matrix formalism is
developed to address both coherent and incoherent transport properties. The
coherent case corresponds to elastic scattering by static defects, which is
dominant at low temperatures, while the incoherent case provides a
phenomenological description of the inelastic scattering present in real
physical systems at room temperature. It is found that disorder scattering
increases the amount of spin-mixing of transmitted electrons, reducing the
adiabaticity. This leads, in the incoherent case, to a reduction of conductance
through the domain wall as compared to a uniformly magnetized region which is
similar to the giant magnetoresistance effect. In the coherent case, a
reduction of weak localization, together with a suppression of spin-reversing
scattering amplitudes, leads to an enhancement of conductance due to the domain
wall in the regime of strong disorder. The total effect of a domain wall on the
conductance of a nanowire is studied by incorporating the disordered regions on
either side of the wall. It is found that spin-dependent scattering in these
regions increases the domain wall magnetoconductance as compared to the effect
found by considering only the scattering inside the wall. This increase is most
dramatic in the narrow wall limit, but remains significant for wide walls.Comment: 23 pages, 12 figure
Non-adherence to antipsychotic medication, relapse and rehospitalisation in recent-onset schizophrenia
<p>Abstract</p> <p>Background</p> <p>The aims of this study were to describe outcome with respect to persistent psychotic symptoms, relapse of positive symptoms, hospital admissions, and application of treatment by coercion among patients with recent onset schizophrenia being adherent and non-adherent to anti-psychotic medication.</p> <p>Materials and methods</p> <p>The study included 50 patients with recent onset schizophrenia, schizoaffective or schizophreniform disorders. The patients were clinically stable at study entry and had less than 2 years duration of psychotic symptoms. Good adherence to antipsychotic medication was defined as less than one month without medication. Outcomes for poor and good adherence were compared over a 24-month follow-up period.</p> <p>Results</p> <p>The Odds Ratio (OR) of having a psychotic relapse was 10.27 and the OR of being admitted to hospital was 4.00 among non-adherent patients. Use of depot-antipsychotics were associated with relapses (OR = 6.44).</p> <p>Conclusion</p> <p>Non-adherence was associated with relapse, hospital admission and having persistent psychotic symptoms. Interventions to increase adherence are needed.</p> <p>Trial registration</p> <p>Current Controlled Trials NCT00184509. Key words: Adherence, schizophrenia, antipsychotic medication, admittances, relapse.</p
Building STEM in schools: an Australian cross-case analysis
The Principals as STEM Leaders (PASL) project was an Australian Government-funded national research and professional learning programme for principals, aimed at building STEM leadership capacity. The project involved cluster-based delivery of six learning modules and generation of case studies outlining schools’ different approaches to STEM education and STEM leadership. This article analyses factors contributing to the development of four contrasting schools’ STEM profiles, identifying the unique approaches and leadership strategies each adopted in designing STEM curriculum for meeting the learning needs of their diverse students. It positions these schools’ endeavours within the broader PASL professional learning programme, adding to the limited body of empirical work detailing different approaches schools take to the ‘STEM challenge’, which, for most, presents a disruptive innovation to traditional curriculum and structures. The vital role of school leaders in communicating a clear, evidence-based vision for STEM and also ‘walking the talk’ and being highly engaged in STEM programmes, was a common feature across the cases. This built relational trust, and a strong whole-of-school commitment to and understanding of STEM, to some extent mitigating the challenges of rigid curriculum and external assessment requirements. The study highlights the complex interaction of professional learning, leadership, curriculum design, pedagogy, and school culture in establishing innovative STEM programmes in schools
Study of a Class of Four Dimensional Nonsingular Cosmological Bounces
We study a novel class of nonsingular time-symmetric cosmological bounces. In
this class of four dimensional models the bounce is induced by a perfect fluid
with a negative energy density. Metric perturbations are solved in an analytic
way all through the bounce. The conditions for generating a scale invariant
spectrum of tensor and scalar metric perturbations are discussed.Comment: 16 pages, 10 figure
Theory and Computation of the Spheroidal Wave Functions
In this paper we report on a package, written in the Mathematica computer
algebra system, which has been developed to compute the spheroidal wave
functions of Meixner [J. Meixner and R.W. Schaefke, Mathieusche Funktionen und
Sphaeroidfunktionen, 1954] and is available online
(www.physics.uwa.edu.au/~falloon/spheroidal/spheroidal.html). This package
represents a substantial contribution to the existing software, since it
computes the spheroidal wave functions to arbitrary precision for general
complex parameters mu, nu, gamma and argument z; existing software can only
handle integer mu, nu and does not give arbitrary precision. The package also
incorporates various special cases and computes analytic power series and
asymptotic expansions in the parameter gamma. The spheroidal wave functions of
Flammer [C. Flammer, Spheroidal Wave Functions, 1957] are included as a special
case of Meixner's more general functions. This paper presents a concise review
of the general theory of spheroidal wave functions and a description of the
formulas and algorithms used in their computation, and gives high-precision
numerical examples.Comment: 26 pages, 4 Appendices, 5 Table
Prediction of storm transfers and annual loads with data-based mechanistic models using high-frequency data
Excess nutrients in surface waters, such as phosphorus (P) from agriculture, result in poor water quality, with adverse effects on ecological health and costs for remediation. However, understanding and prediction of P transfers in catchments have been limited by inadequate data and over-parameterised models with high uncertainty. We show that, with high temporal resolution data, we are able to identify simple dynamic models that capture the P load dynamics in three contrasting agricultural catchments in the UK. For a flashy catchment, a linear, second-order (two pathways) model for discharge gave high simulation efficiencies for short-term storm sequences and was useful in highlighting uncertainties in out-of-bank flows. A model with nonlinear rainfall input was appropriate for predicting seasonal or annual cumulative P loads where antecedent conditions affected the catchment response. For second-order models, the time constant for the fast pathway varied between 2 and 15 h for all three catchments and for both discharge and P, confirming that high temporal resolution data are necessary to capture the dynamic responses in small catchments (10–50 km2/. The models led to a better understanding of the dominant nutrient transfer modes, which will be helpful in determining phosphorus transfers following changes in precipitation patterns in the future
Implications of climate change for agricultural productivity in the early twenty-first century
This paper reviews recent literature concerning a wide range of processes through which climate change could potentially impact global-scale agricultural productivity, and presents projections of changes in relevant meteorological, hydrological and plant physiological quantities from a climate model ensemble to illustrate key areas of uncertainty. Few global-scale assessments have been carried out, and these are limited in their ability to capture the uncertainty in climate projections, and omit potentially important aspects such as extreme events and changes in pests and diseases. There is a lack of clarity on how climate change impacts on drought are best quantified from an agricultural perspective, with different metrics giving very different impressions of future risk. The dependence of some regional agriculture on remote rainfall, snowmelt and glaciers adds to the complexity. Indirect impacts via sea-level rise, storms and diseases have not been quantified. Perhaps most seriously, there is high uncertainty in the extent to which the direct effects of CO2 rise on plant physiology will interact with climate change in affecting productivity. At present, the aggregate impacts of climate change on global-scale agricultural productivity cannot be reliably quantified
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The Views of Mental Health Manager Towards the Use of a Family Work Model for Psychosis in Guangzhou, China
Family Interventions in Psychosis (FIP) have been promoted internationally but have been criticised for being based on western cultural models. This paper reports on a focus group study with 10 Integrated Mental Health Service Managers in Guangzhou, China using thematic analysis. Managers believed FIP might benefit families but identified potential difficulties due to (a) families avoiding services due to the ‘shame’ of mental illness (b) unrealistic expectations of services amongst families (c) deferral to ‘key decision-makers’ within families when discussing family issues with workers. The findings indicate that FIP work should focus on interaction between carers in the first instance with service users being introduced into sessions at a later date and that more attention needs to be given by the research community to how FIP may be adapted to cultural norms within China
Psychometric Properties of an Assessment for Mental Health Recovery Programs
The concept of recovery can be operationalized from either the point of view of the consumer, or from the perspective of the agency providing services. The Milestones of Recovery Scale (MORS) was created to capture aspects of recovery from the agency perspective. Evidence establishing the psychometric properties of the MORS was obtained in three efforts: Inter-rater reliability using staff at The Village, a multi-service organization serving the homeless mentally ill in Long Beach, California; inter-rater reliability was also obtained from Vinfen Corporation, a large provider of housing services to mentally ill persons in Boston, Massachusetts. A test–retest reliability study was conducted using staff rating of clients at The Village, and evidence for validity was obtained using the Level of Care Utilization System (LOCUS) as a validity measure. The intra-class correlation coefficient for the inter-rater reliability study was r = .85 (CI .81, .89) for The Village and r = .86 (CI .80, .90) for Vinfen Corporation; test–retest reliability was r = .85 (CI .81, .87); and validity coefficients for the LOCUS were at or above r = .49 for all subscales except one. There is sufficient evidence for the reliability and validity of the MORS
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