225 research outputs found
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
What have we learnt from EUPORIAS climate service prototypes?
The international effort toward climate services, epitomised by the development of the Global Framework for Climate Services and, more recently the launch of Copernicus Climate Change Service has renewed interest in the users and the role they can play in shaping the services they will eventually use. Here we critically analyse the results of the five climate service prototypes that were developed as part of the EU funded project EUPORIAS.
Starting from the experience acquired in each of the projects we attempt to distil a few key lessons which, we believe, will be relevant to the wider community of climate service developers
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
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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
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
Two-stage evolution of mantle peridotites from the Stalemate Fracture Zone, northwestern Pacific
This paper reports the results of a mineralogical study of 14 mantle peridotite samples dredged in 2009 from the eastern slope of the northwestern segment of the Stalemate Ridge in the northwestern Pacific during cruise SO201-KALMAR Leg 1b of the R/V Sonne. The sample collection included four serpentinized and silicified dunites and ten variably serpentinized lherzolites. The compositions of primary minerals (clinopyroxene, orthopyroxene, and spinel) change systematically from the lherzolites to dunites. Spinel from the lherzolites shows higher Mg# and lower Cr# values (0.65-0.68 and 0.26-0.33, respectively) compared with spinel from the dunites (Mg# = 0.56-0.64 and Cr# = 0.38-0.43). Clinopyroxene from the lherzolites is less magnesian (Mg# = 91.7-92.4) than clinopyroxene from dunite sample DR37-3 (Mg# = 93.7). Based on the obtained data, it was concluded that the lherzolites of the Stalemate Fracture Zone were derived by 10-12% near-fractional melting of a DMM-type depleted mantle reservoir beneath the Kula-Pacific spreading center. The dunites were produced by interaction of residual lherzolites with sodium- and titaniumrich melt and are probably fragments of a network of dunite channels in the shallow mantle. The moderately depleted composition of minerals clearly distinguishes the lherzolites from the strongly depleted peridotites of the East Pacific Rise and indicates the existence of slow-spreading mid-ocean ridges in the Pacific Ocean during the Cretaceous-Paleogene
A framework for the cross-sectoral integration of multi-model impact projections: land use decisions under climate impacts uncertainties
Climate change and its impacts already pose considerable challenges for societies that will further increase with global warming (IPCC, 2014a, b). Uncertainties of the climatic response to greenhouse gas emissions include the potential passing of large-scale tipping points (e.g. Lenton et al., 2008; Levermann et al., 2012; Schellnhuber, 2010) and changes in extreme meteorological events (Field et al., 2012) with complex impacts on societies (Hallegatte et al., 2013). Thus climate change mitigation is considered a necessary societal response for avoiding uncontrollable impacts (Conference of the Parties, 2010). On the other hand, large-scale climate change mitigation itself implies fundamental changes in, for example, the global energy system. The associated challenges come on top of others that derive from equally important ethical imperatives like the fulfilment of increasing food demand that may draw on the same resources. For example, ensuring food security for a growing population may require an expansion of cropland, thereby reducing natural carbon sinks or the area available for bio-energy production. So far, available studies addressing this problem have relied on individual impact models, ignoring uncertainty in crop model and biome model projections. Here, we propose a probabilistic decision framework that allows for an evaluation of agricultural management and mitigation options in a multi-impactmodel setting. Based on simulations generated within the Inter-Sectoral Impact Model Intercomparison Project (ISI-MIP), we outline how cross-sectorally consistent multi-model impact simulations could be used to generate the information required for robust decision making.
Using an illustrative future land use pattern, we discuss the trade-off between potential gains in crop production and associated losses in natural carbon sinks in the new multiple crop- and biome-model setting. In addition, crop and water model simulations are combined to explore irrigation increases as one possible measure of agricultural intensification that could limit the expansion of cropland required in response to climate change and growing food demand. This example shows that current impact model uncertainties pose an important challenge to long-term mitigation planning and must not be ignored in long-term strategic decision making
Influence of non-nucleoside reverse transcriptase inhibitors (efavirenz and nevirapine) on the pharmacodynamic activity of gliclazide in animal models
<p>Abstract</p> <p>Background</p> <p>Type 2 diabetes may occur as a result of HIV infection and/or its treatment. Gliclazide is a widely used drug for the treatment of type 2 diabetes. Efavirenz and nevirapine are widely used non-nucleoside reverse transcriptase inhibitors for the treatment of HIV infection. The role of Efavirenz and nevirapine on the pharmacodynamic activity of gliclazide is not currently known. The objective of this study was to examine the effect of oral administration of efavirenz and nevirapine on blood glucose and investigate their effect on the activity of gliclazide in rats (normal and diabetic) and rabbits to evaluate the safety and effectiveness of the combination.</p> <p>Methods</p> <p>Studies in normal and alloxan induced diabetic rats were conducted with oral doses of 2 mg/kg bd. wt. of gliclazide, 54 mg/kg bd. wt. of efavirenz or 18 mg/kg bd. wt. of nevirapine and their combination with adequate washout periods in between treatments. Studies in normal rabbits were conducted with 5.6 mg/1.5 kg bd. wt. of gliclazide, 42 mg/1.5 kg bd. wt. of efavirenz or 14 mg/1.5 kg bd. wt. of nevirapine and their combination given orally. Blood samples were collected at regular time intervals in rats from retro orbital puncture and by marginal ear vein puncture in rabbits. All the blood samples were analysed for blood glucose by GOD/POD method.</p> <p>Results</p> <p>Efavirenz and nevirapine alone have no significant effect on the blood glucose level in rats and rabbits. Gliclazide produced hypoglycaemic/antidiabetic activity in normal and diabetic rats with peak activity at 2 h and 8 h and hypoglycaemic activity in normal rabbits at 3 h. In combination, efavirenz reduced the effect of gliclazide in rats and rabbits, and the reduction was more significant with the single dose administration of efavirenz than multiple dose administration. In combination, nevirapine has no effect on the activity of gliclazide in rats and rabbits.</p> <p>Conclusion</p> <p>Thus, it can be concluded that the combination of efavirenz and gliclazide may need dose adjustment and care should be taken when the combination is prescribed for their clinical benefit in diabetic patients. The combination of nevirapine and gliclazide was safe. However, further studies are warranted.</p
DeLLITE Depression in late life: an intervention trial of exercise. Design and recruitment of a randomised controlled trial
<p>Abstract</p> <p>Background</p> <p>Physical activity shows potential in combating the poor outcomes associated with depression in older people. Meta-analyses show gaps in the research with poor trial design compromising certainty in conclusions and few programmes showing sustained effects.</p> <p>Methods/design</p> <p>The Depression in Late Life: an Intervention Trial of Exercise (DeLLITE) is a 12 month randomised controlled trial of a physical activity intervention to increase functional status in people aged 75 years and older with depressive symptoms. The intervention involves an individualised activity programme based on goal setting and progression of difficulty of activities delivered by a trained nurse during 8 home visits over 6 months. The control group received time matched home visits to discuss social contacts and networks. Baseline, 6 and 12 months measures were assessed in face to face visits with the primary outcome being functional status (SPPB, NEADL). Secondary outcomes include depressive symptoms (Geriatric Depression Scale), quality of life (SF-36), physical activity (AHS Physical Activity Questionnaire) and falls (self report).</p> <p>Discussion</p> <p>Due to report in 2008 the DeLLITE study has recruited 70% of those eligible and tests the efficacy of a home based, goal setting physical activity programme in improving function, mood and quality of life in older people with depressive symptomatology. If successful in improving function and mood this trial could prove for the first time that there are long term health benefit of physical activity, independent of social activity, in this high risk group who consume excess health related costs.</p> <p>Trial registration</p> <p>Australian and New Zealand Clinical Trials Register ACTRN12605000475640</p
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