106 research outputs found

    Students\u27 perceptions of native and non-native English-speaking teachers and their influence on students\u27 motivation

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    The present study aims to investigate students\u27 perceptions of native English-speaking teachers (NEST) and non-native English-speaking teachers (NNEST) and the techniques used by both types of teachers to influence students\u27 motivation. Both qualitative and quantitative research methods were employed to answer the research questions. A sample of 82 Egyptian learners enrolled in the Intensive English Program (IEP) at the American University in Cairo (AUC) and a sample of two native IEP teachers and two non-native IEP teachers participated in the study. A questionnaire was sent to students to identify students\u27 perceptions of the instructional practices and motivational techniques utilized by both NESTs and NNESTs. A classroom observation scheme was also used to document the minute-by-minute motivational techniques used by teachers. Triangulating the results, the investigator conducted semi-structured interviews for further in-depth analysis of the research questions. The results showed that students hold more positive perceptions towards the instructional practices and motivational techniques used by the non-native English-speaking teacher. The findings also revealed that the motivational techniques used by both types of teachers in the teaching process varied

    Predicting water quality and ecological responses

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    Abstract Changes to climate are predicted to have effects on freshwater streams. Stream flows are likely to change, with implications for freshwater ecosystems and water quality. Other stressors such as population growth, community preferences and management policies can be expected to interact in various ways with climate change and stream flows, and outcomes for freshwater ecosystems and water quality are uncertain. Managers of freshwater ecosystems and water supplies could benefit from being able to predict the scales of likely changes. This project has developed and applied a linked modelling framework to assess climate change impacts on water quality regimes and ecological responses. The framework is designed to inform water planning and climate adaptation activities. It integrates quantitative tools, and predicts relationships between future climate, human activities, water quality and ecology, thereby filling a gap left by the considerable research effort so far invested in predicting stream flows. The modelling framework allows managers to explore potential changes in the water quality and ecology of freshwater systems in response to plausible scenarios for climate change and management adaptations. Although set up for the Upper Murrumbidgee River catchment in southern NSW and ACT, the framework was planned to be transferable to other regions where suitable data are available. The approach and learning from the project appear to have the potential to be broadly applicable. We selected six climate scenarios representing minor, moderate and major changes in flow characteristics for 1oC and 2oC temperature increases. These were combined with four plausible alternative management adaptations that might be used to modify water supply, urban water demand and stream flow regimes in the Upper Murrumbidgee catchment. The Bayesian Network (BN) model structure we used was developed using both a ‘top down’ and ‘bottom up’ approach. From analyses combined with expert advice, we identified the causal structure linking climate variables to stream flow, water quality attributes, land management and ecological responses (top down). The ‘bottom up’ approach focused on key ecological outcomes and key drivers, and helped produce efficient models. The result was six models for macroinvertebrates, and one for fish. In the macroinvertebrate BN models, nodes were discretised using statistical/empirical derived thresholds using new techniques. The framework made it possible to explore how ecological communities respond to changes in climate and management activities. Particularly, we focused on the effects of water quality and quantity on ecological responses. The models showed a strong regional response reflecting differences across 18 regions in the catchment. In two regions the management alternatives were predicted to have stronger effects than climate change. In three other regions the predicted response to climate change was stronger. Analyses of water quality suggested minor changes in the probability of water quality exceeding thresholds designed to protect aquatic ecosystems. The ‘bottom up’ approach limited the framework’s transferability by being specific to the Upper Murrumbidgee catchment data. Indeed, to meet stakeholder questions models need to be specifically tailored. Therefore the report proposes a general model-building framework for transferring the approach, rather than the models, to other regions.  Please cite this report as: Dyer, F, El Sawah, S, Lucena-Moya, P, Harrison, E, Croke, B, Tschierschke, A, Griffiths, R, Brawata, R, Kath, J, Reynoldson, T, Jakeman, T 2013 Predicting water quality and ecological responses, National Climate Change Adaptation Research Facility, Gold Coast, pp. 110 Changes to climate are predicted to have effects on freshwater streams. Stream flows are likely to change, with implications for freshwater ecosystems and water quality. Other stressors such as population growth, community preferences and management policies can be expected to interact in various ways with climate change and stream flows, and outcomes for freshwater ecosystems and water quality are uncertain. Managers of freshwater ecosystems and water supplies could benefit from being able to predict the scales of likely changes. This project has developed and applied a linked modelling framework to assess climate change impacts on water quality regimes and ecological responses. The framework is designed to inform water planning and climate adaptation activities. It integrates quantitative tools, and predicts relationships between future climate, human activities, water quality and ecology, thereby filling a gap left by the considerable research effort so far invested in predicting stream flows. The modelling framework allows managers to explore potential changes in the water quality and ecology of freshwater systems in response to plausible scenarios for climate change and management adaptations. Although set up for the Upper Murrumbidgee River catchment in southern NSW and ACT, the framework was planned to be transferable to other regions where suitable data are available. The approach and learning from the project appear to have the potential to be broadly applicable. We selected six climate scenarios representing minor, moderate and major changes in flow characteristics for 1oC and 2oC temperature increases. These were combined with four plausible alternative management adaptations that might be used to modify water supply, urban water demand and stream flow regimes in the Upper Murrumbidgee catchment. The Bayesian Network (BN) model structure we used was developed using both a ‘top down’ and ‘bottom up’ approach. From analyses combined with expert advice, we identified the causal structure linking climate variables to stream flow, water quality attributes, land management and ecological responses (top down). The ‘bottom up’ approach focused on key ecological outcomes and key drivers, and helped produce efficient models. The result was six models for macroinvertebrates, and one for fish. In the macroinvertebrate BN models, nodes were discretised using statistical/empirical derived thresholds using new techniques. The framework made it possible to explore how ecological communities respond to changes in climate and management activities. Particularly, we focused on the effects of water quality and quantity on ecological responses. The models showed a strong regional response reflecting differences across 18 regions in the catchment. In two regions the management alternatives were predicted to have stronger effects than climate change. In three other regions the predicted response to climate change was stronger. Analyses of water quality suggested minor changes in the probability of water quality exceeding thresholds designed to protect aquatic ecosystems. The ‘bottom up’ approach limited the framework’s transferability by being specific to the Upper Murrumbidgee catchment data. Indeed, to meet stakeholder questions models need to be specifically tailored. Therefore the report proposes a general model-building framework for transferring the approach, rather than the models, to other regions.&nbsp

    Effects of shade level and microenvironment on vegetative growth, physiological and biochemical characteristics of transplanted cucumber (Cucumis sativus)

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    Growing vegetables through transplantation under black shade nets is currently becoming popular to provide protection from high intensities of light and high temperatures. This study evaluated the effects of shade level on microenvironment, vegetative growth, photosynthetic pigments, chlorophyll a fluorescence, osmoprotectants, plant water status and leaf mineral nutrients of greenhouse-grown summer cucumber transplants at 25%, 50%, 63%, and 75% shade levels. Solar radiation and tempera-ture decreased with increased shading levels. Average daily temperatures were approximately decreased by 1.5oC under 75% shade nets compared to the 25% shade nets. Vegetative growth characteristics, photosynthetic pigments, chlorophyll a fluorescence (Fv/Fm, Fv/F0, and PI), dehydration tolerance and Leaf N, P and K concentrations increased when shade level increased. Chlorophyll a fluorescence (Fv/Fm, Fv/F0, and PI) reduced with the increase of solar radiation levels. Also, clear decreases in free proline, soluble sugars and total free amino acids in both experiments with increased shade level have been observed. Additionally, relative water content (RWC), membrane stability index (MSI) and electrolyte leakage (EL) of cucumber transplants were significantly affected in both experiments by shade level. Moreover Shade level affected leaf mineral nutrient but the effect differed among nutrients concentration. This study concluded that, nets with higher shading levels (63 and/or 75%) are a potential alternative to alleviate photo-inhibition and heat stress in cucumber transplants production

    Balloon Valvuloplasty of Aortic Valve Stenosis in Childhood: Midterm Results in a Children’s Hospital, Mansoura University, Egypt

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    Background Balloon valvuloplasty was established as an alternative to surgery for treatment of aortic valve stenosis in childhood. Acute complications after balloon dilatation including aortic insufficiency or early death were described. Aim of Work To analyze early outcome and midterm results of balloon aortic valvuloplasty (BAV) in Children's Hospital, Mansoura University, Egypt. Subjects and Methods Between April 2005–June 2008, all consecutive patients of age <18 years treated for aortic valve stenosis (AVS) with BAV were analyzed retrospectively. The study included 21 patients; 17 males, and 4 females. Their age ranged from the neonatal period to 10 years (mean age 5.6 ± 3.7 years). Patients with gradient ≥50 mmHg and aortic valve insufficiency (AI) up to grade I were included. All patients had isolated aortic valve stenosis except 3 patients (14.3%) had associated aortic coarctation. Six patients (28.6%) had bicuspid aortic valve. All patients had normal myocardial function except one (4.8%) had FS 15%. The duration of follow up was (mean ± SD: 18.5 ± 11.7 months). Results Femoral artery approach was used in 20 patients (95.2%) and carotid artery in one neonate (4.8%). Balloon/annulus ratio was 0.83 ± 0.04. Significant reduction in pressure gradient was achieved (mean 66.7 ± 9.8 mmHg to 20.65 ± 2.99 mmHg) ( P < 0.001). Nine patients (42.8%) developed grade I AI, 2 patients (9.5%) developed grade II AI and 1 patient (4.8%) developed grade III AI. Two early deaths (9.5%); one died due to heart failure caused by grade IV AI and a neonate died because of severely compromised LV function. One patient (4.8%) had femoral artery occlusion necessitating anticoagulation. Patients remained free from re-intervention during follow up. Conclusion Balloon valvuloplasty of aortic valve stenosis significantly reduces gradient with low morbidity and mortality in children

    Diamond optomechanical crystals

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    Cavity-optomechanical systems realized in single-crystal diamond are poised to benefit from its extraordinary material properties, including low mechanical dissipation and a wide optical transparency window. Diamond is also rich in optically active defects, such as the nitrogen-vacancy (NV) and silicon-vacancy (SiV) centers, which behave as atom-like systems in the solid state. Predictions and observations of coherent coupling of the NV electronic spin to phonons via lattice strain has motivated the development of diamond nanomechanical devices aimed at realization of hybrid quantum systems, in which phonons provide an interface with diamond spins. In this work, we demonstrate diamond optomechanical crystals (OMCs), a device platform to enable such applications, wherein the co-localization of ~ 200 THz photons and few to 10 GHz phonons in a quasi-periodic diamond nanostructure leads to coupling of an optical cavity field to a mechanical mode via radiation pressure. In contrast to other material systems, diamond OMCs operating in the resolved-sideband regime possess large intracavity photon capacity (> 105^5) and sufficient optomechanical coupling rates to reach a cooperativity of ~ 20 at room temperature, allowing for the observation of optomechanically induced transparency and the realization of large amplitude optomechanical self-oscillations

    Implementation Critical Success Factors (CSFs) for ERP: Do they contribute to implementation success and post-implementation performance?

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    Extent: 55 p.Frequent commentaries in the literature have stated that certain critical success factors (CSFs) have to be accomplished in an organisation for an Enterprise Resource Planning (ERP) system project to be successful. In this study we argue and demonstrate empirically that success in implementing an ERP system and in gaining performance improvement should be conceptualised as two separate dependent variables. The distinction is made because the former aspect is based upon project delivery outcomes, while the latter assesses post-ERP project performance. We question whether some factors labelled as 'critical' success factors for ERP projects are in practice actually critical for achieving success in implementation and improving output performance. To examine this we report an empirical study that has investigated whether four major CSFs are in practice critical for achieving organisational performance improvements, and the role that successful implementation may play in influencing the relationship between CSFs and improvements in organisational performance. A conceptual model was devised and then analysed using structural equation modelling, based on data collected from 217 organisations. We found that some CSFs were not critical to achieve success in ERP implementation but were critical to help an organisational achieve performance improvement from an ERP system. Additionally, we also found that achieving successful ERP system implementation mediates the degree to which a CSF affects output performance improvement. The managerial and research implications of these findings are discussed and the limitations of the study noted.Jiwat Ram, David Corkindale, Ming-Lu W

    Australasian Simulation Congress SimTect 2016

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    This paper is a part of an ongoing research project focused on developing and testing a “modelling by design” approach for building system dynamics models to support both decision making and education purposes. To motivate the development and evaluation of the approach, we use multiple case-studies driven methodology. Our case studies are focused in the areas related to defense capability-based planning and analysis. In this paper, we outline the development approach, define the problem domain, and give an early glimpse on the modelling framework, and its key component
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