1,156 research outputs found

    Computer-Aided Acquisition of Writing Skills

    Get PDF
    This article presents the results of a review of the literature questioning whether and to what extent computers can be used as a means of instruction for the guided acquisition of communicative writing skills in higher education. To answer this question, the present paper first explores the characteristics of acquiring these skills from a cognitive-psychological perspective, as well as the characteristics and behaviour of expert writers. On this basis, the paper then describes whether and how computer-aided instruction can relieve teachers of certain duties associated with writing instruction, allowing them more time to perform tasks which fully utilise their unique capabilities

    Spatio-temporal mapping of daily photosynthesis in drought conditions using remote sensing observations and in-situ measurements:abstract

    Get PDF
    Reliable spatio-temporal information about the photosynthesis and its dependence on environmental factors, is crucial for vegetation productivity monitoring, water resources management, and detection of climate change effects.. In this study, we investigated the relationship between time series of Landsat (TM5 and ETM7) optical data, soil moisture measurements and canopy daily photosynthesis of annual C3 grasses at a Fluxnet site (US-Var) during a prolonged drought episode from January to August 2004. By using the ‘Soil -Canopy Observation of Photosynthesis and Energy fluxes’ (SCOPE) model, time series maps of photosynthesis were simulated via Landsat retrieved vegetation properties maps [notably Leaf Area Index (LAI), leaf chlorophyll content (Cab), leaf water content (Cw), leaf dry matter content (Cdm), the leaf inclination distribution function (LIDF) and the senescent material content (Cs)], locally measured weather data and in-situ soil moisture data. The generated maps of photosynthesis simulated by the SCOPE model were validated at a Fluxnet site (US-Var). The comparison between daily photosynthesis simulations and measurements shows that considerable drought effects on photosynthesis are ‘visible’ in the Landsat optical bands. However, the most accurate photosynthesis maps are obtained when soil moisture information is added as an extra source of input data to the SCOPE simulations. The results from this study indicate that the combined use of optical remote sensing observations and in-situ measured soil moisture data has a great potential to capture the drought effects on the grass canopy photosynthesis

    An Intercomparison of Satellite-Based Daily Evapotranspiration Estimates under Different Eco-Climatic Regions in South Africa

    Get PDF
    Knowledge of evapotranspiration (ET) is essential for enhancing our understanding of the hydrological cycle, as well as for managing water resources, particularly in semi-arid regions. Remote sensing offers a comprehensive means of monitoring this phenomenon at different spatial and temporal intervals. Currently, several satellite methods exist and are used to assess ET at various spatial and temporal resolutions with various degrees of accuracy and precision. This research investigated the performance of three satellite-based ET algorithms and two global products, namely land surface temperature/vegetation index (TsVI), Penman–Monteith (PM), and the Meteosat Second Generation ET (MET) and the Global Land-surface Evaporation: the Amsterdam Methodology (GLEAM) global products, in two eco-regions of South Africa. Daily ET derived from the eddy covariance system from Skukuza, a sub-tropical, savanna biome, and large aperture boundary layer scintillometer system in Elandsberg, a Mediterranean, fynbos biome, during the dry and wet seasons, were used to evaluate the models. Low coefficients of determination (R2) of between 0 and 0.45 were recorded on both sites, during both seasons. Although PM performed best during periods of high ET at both sites, results show it was outperformed by other models during low ET times. TsVI and MET were similarly accurate in the dry season in Skukuza, as GLEAM was the most accurate in Elandsberg during the wet season. The conclusion is that none of the models performed well, as shown by low R2 and high errors in all the models. In essence, our results conclude that further investigation of the PM model is possible to improve its estimation of low ET measurements

    FluorMODgui V3.0: A Graphic User Interface for the Spectral Simulation of Leaf and Canopy Chlorophyll Fluorescence

    Get PDF
    The FluorMODgui Graphic User Interface (GUI) software package developed within the frame of the FluorMOD project Development of a Vegetation Fluorescence Canopy Model is presented in this manuscript. The FluorMOD project was launched in 2002 by the European Space Agency (ESA) to advance the science of vegetation fluorescence simulation through the development and integration of leaf and canopy fluorescence models based on physical methods. The design of airborne or space missions dedicated to the measurement of solar-induced chlorophyll fluorescence using remote-sensing instruments require physical methods for quantitative feasibility analysis and sensor specification studies. The FluorMODgui model developed as part of this project is designed to simulate the effects of chlorophyll fluorescence at leaf and canopy levels using atmospheric inputs, running the leaf model, FluorMODleaf, and the canopy model, FluorSAIL, independently, through a coupling scheme, and by a multiple iteration protocol to simulate changes in the viewing geometry and atmospheric characteristics. Inputs for the FluorMODleaf model are the number of leaf layers, chlorophyll a+b content, water equivalent thickness, dry matter content, fluorescence quantum efficiency, temperature, species type, and stoichiometry. Inputs for the FluorSAIL canopy model are a MODTRAN-4 6-parameter spectra or measured direct horizontal irradiance and diffuse irradiance spectra, a soil reflectance spectrum, leaf reflectance & transmittance spectra and a excitation-fluorescence response matrix in upward and downward directions (all from FluorMODleaf), 2 PAR-dependent coefficients for the fluorescence response to light level, relative azimuth angle and viewing zenith angle, canopy leaf area index, leaf inclination distribution function, and a hot spot parameter. Outputs available in the 400-1000 nm spectral range from the graphical user interface, FluorMODgui, are the leaf spectral reflectance and transmittance, and the canopy reflectance, with and without fluorescence effects. In addition, solar and sky irradiance on the ground, radiance with and without fluorescence on the ground, and top-of-atmosphere (TOA) radiances for bare soil and surroundings same as target are also produced. The models and documentation regarding the FluorMOD project can be downloaded at http://www.ias.csic.es/fluormod

    A system of networks and continuing education for physical therapists in rheumatology: a feasibility study

    Get PDF
    PURPOSE: To evaluate the feasibility of regional physical therapy networks including continuing education in rheumatology. The aim of these networks was to improve care provided by primary care physical therapists by improving specific knowledge, technical and communicative skills and the collaboration with rheumatologists. METHODS: In two regions in The Netherlands continuing education (CE) programmes, consisting of a 5-day postgraduate training course followed by bimonthly workshops and teaching practices, were organised simultaneously. Network activities included consultations, newsletters and the development of a communication guideline. Endpoint measures included the participation rate, compliance, quality of the CE programme, teaching practices, knowledge, network activities, communication, number of patients treated and patient satisfaction. RESULTS: Sixty-three physical therapists out of 193 practices (33%) participated in the project. They all completed the education programmes and were formally registered. All evaluations of the education programmes showed positive scores. Knowledge scores increased significantly directly after the training course and at 18 months. A draft guideline on communication between physical therapists and rheumatologists was developed, and 4 newsletters were distributed. A substantial proportion of physical therapists and rheumatologists reported improved communication at 18 months. The mean number of patients treated by physical therapists participating in the networks increased significantly. Patients' satisfaction scores within the networks were significantly higher than those from outside the networks at 18 months. CONCLUSIONS: Setting up a system of networks for continuing education for physical therapists regarding the treatment of patients with rheumatic diseases is feasible. Further research will focus on the effectiveness of the system and its implementation on a larger scale

    The oncological outcomes of isolated limb perfusion and neo-adjuvant radiotherapy in soft tissue sarcoma patients:A nationwide multicenter study

    Get PDF
    Introduction: Patients with locally extensive high-grade extremity soft tissue sarcomas (eSTS) are often presented in multidisciplinary teams to decide between ablative surgery (amputation) or limb-salvage surgery supplemented with either neo-adjuvant radiotherapy (RT) or induction isolated limb perfusion (ILP). In The Netherlands, ILP typically aims to reduce the size of tumors that would otherwise be considered irresectable, whereas neo-adjuvant RT aims mainly at improving local control and reducing morbidity of required marginal margins. This study presents a 15-year nationwide cohort to describe the oncological outcomes of both pre-operative treatment strategies. Methods: All consecutive patients with locally extensive primary high-grade eSTS surgically treated between 2000 and 2015 at five tertiary sarcoma centers that received neo-adjuvant ILP or RT were included. 169 patients met the inclusion criteria (89 ILP, 80 RT). Median follow-up was 7.3 years. Results: Limb salvage was achieved in 84% of cases in the ILP group (80% for patients with amputation indication) and 96% of cases in the RT group. 5-Year overall survival was 47% in the ILP group, 69% in the RT group. 5-Year local recurrence rate was 14% in the ILP group, 10% in the RT group. Distant metastasis rate was 55% in the ILP group, 36% in the RT group. Conclusion: We find oncological outcomes and limb salvage rates in line with existing literature for both treatment modalities. Whether the tumor was locally advanced with an indication for induction therapy to prevent amputation or morbid surgery appeared to be the main determinant in choosing between neo-adjuvant ILP or RT

    Self-cleaning and colour-preserving efficiency of photocatalytic concrete: case study of the Jubilee Church in Rome

    Get PDF
    The Jubilee Church in the south-eastern outskirts of Rome is one of the first buildings constructed with super white reinforced concrete with self-cleaning photocatalytic cement. However, 16 years after the opening of the building, the self-cleaning and colour-preserving properties arising from the titania particles (TiO2) within the concrete mix are not meeting the design requirements and the concrete is showing premature evidence of decay. While the form of the decay is affecting the appearance of the building and not its structural soundness, the ageing pattern of the building's components is resulting in a high maintenance cost, one not easily affordable within the ordinary budget supported by a small parish. This study comprises the first comprehensive step in understanding the causes of the accelerated ageing pattern of the concrete, highlighting methods to improve the long-term durability of the concrete and therefore reduce the cost of its maintenance. Moreover, this research offered the opportunity to test the durability and the effectiveness of the TiO2 in the real conditions on an actual building featuring non-standard geometries. The findings highlight how the ageing pattern directly connects with the geometry of the building and inadequate consideration of the local weathering at the design stage
    • …
    corecore