557 research outputs found

    Calibration and validation of SALTMED model under dry and wet year conditions using chickpea field data from Southern Portugal

    Get PDF
    The SALTMED model is one of the few available generic models that can be used to simulate crop growth with an integrated approach that accounts for water, crop, soil, and field management. It is a physically based model using the well-known water and solute transport, evapotranspiration, and water uptake equations. In this paper, the model simulated chickpea growth under different irrigation regimes and a Mediterranean climate. Five different chickpea varieties were studied under irrigation regimes ranging from rainfed to 100 % crop water requirements, in a dry and a wet year. The calibration of the model using one of the chickpea varieties was sufficient for simulating the other varieties, not requiring a specific calibration for each individual chickpea variety. The results of calibration and validation of the SALTMED model showed that the model can simulate very accurately soil moisture content, grain yield, and total dry biomass of different chickpea varieties, in both wet and dry years. This new version of the SALTMED model (v. 3.02.09) has more features and possibilities than the previous versions, providing academics and professionals with a very good tool to manage water, soil, and crops

    An Investigation into Mechanical Properties of Ductile Cast Iron with Different Heat Treatment Processes

    Get PDF
    The mechanical properties as well as microstructure of the ductile cast iron (DCI) are most likely affected by heat treatments. In this work, the mechanical properties of different heat treated of DCI alloy were investigated. Two heat treatment (HT) processes were conducted for DCI; austempering and quenching followed by lower tempering. The melted alloy of DCI was poured in Y-block, from which the specimens of the mechanical tests were prepared. Experimental tests were carried out to investigate the effect of these HT processes on the mechanical properties. A comparison between mechanical properties due to HT and as cast DCI are presented and discussed. The results showed that there is a difference in microstructure, homogeneity, wear rate and compression of DCI based on the conducted heat treatment

    Qualitative exploration of the renal stone patients' experience and development of the renal stone-specific patient-reported outcome measure

    Get PDF
    OBJECTIVES: To investigate the experience of patients living with renal calculi via a qualitative methodology, aiming to develop and validate a disease-specific patient-reported outcome measure (PROM) for renal stones, the Cambridge Renal Stone PROM (CReSP). PATIENTS, SUBJECTS AND METHODS: Patients with radiologically confirmed renal calculi who had undergone a range of management options were invited to focus groups or semi-structured interviews to elicit patient input and generate the PROM content. The developed renal stone PROM underwent validity studies included Cronbach's α for internal consistency, Spearman's and Pearson's correlation coefficients for test-retest reliability. Discriminant validity was assessed by Pearson's correlation coefficients vs the EuroQol five-dimensional five-level questionnaire (EQ-5D-5L). Our project has Health and Social Care Research Ethics Committee approval. RESULTS: A total of 106 subjects participated in creating the newly developed PROM. In all, 36 patients were invited to 22 semi-structured interviews and four focus groups, until reaching saturation. Major issues reported, and themes selected for the renal stone PROM included pain, anxiety, limitations to social life and tiredness, urinary symptoms, dietary changes' impacts, and gastrointestinal tract symptoms. Reliability analysis for 30 patients to determine internal consistency using Cronbach's α with a mean (range) of 0.91 (0.90-0.93) within domains and Cronbach's α between domains was 0.92. Average inter-item Pearson's and Spearman's correlation within domains was performed, with a Pearson's correlation mean (range) of 0.77 (0.73-0.85) and Spearman's correlation mean (range) of 0.72 (0.63-0.77). The test-retest Pearson's correlation mean (range) was 0.85 (0.57-0.95). Validity assessment was performed for 20 patients vs 20 controls. Pearson's correlation with EQ-5D-5L was -0.74, showing the newly developed PROM successfully discriminated patients with kidney stones. Our final renal stone PROM consists of 14 questions that are rated on a Likert scale; the higher the score, the worse the effect on a patient's quality of life. CONCLUSIONS: Although pain was the most frequent symptom, other health-related and social well-being issues significantly impacted patients' lives. Our validated patient-derived CReSP is a new instrument, specifically tailored to measure renal stone disease health outcomes from the patient's point of view

    Energy Distribution of a Stationary Beam of Light

    Full text link
    Aguirregabiria et al showed that Einstein, Landau and Lifshitz, Papapetrou, and Weinberg energy-momentum complexes coincide for all Kerr-Schild metric. Bringely used their general expression of the Kerr-Schild class and found energy and momentum densities for the Bonnor metric. We obtain these results without using Aguirregabiria et al results and verify that Bringley's results are correct. This also supports Aguirregabiria et al results as well as Cooperstock hypothesis. Further, we obtain the energy distribution of the space-time under consideration.Comment: Latex, no figures [Admin note: substantial overlap with gr-qc/9910015 and hep-th/0308070

    Jerusalem artichoke (Helianthus tuberosus L.): A review of in vivo and in vitro propagation

    Get PDF
    Jerusalem artichoke (Helianthus tuberosus L.) is an old tuber crop with a recently renewed interest in multipurpose improvement. It is a perennial tuberous plant rich in inulin and is a potential energy crop. During food shortages in times of war Jerusalem artichoke received more attention by scientists and farmers because of its multiple uses as a vegetable, medicinal plant, forage plant and source for biofuel. The energy crisis of the 1970s motivated research on Jerusalem artichoke for biofuel as the aboveground plant biomass and the tubers can be used for this purpose. There are different methods to propagate Jerusalem artichoke using tubers, rhizomes, slips (transplants derived from sprouted tubers), stem cuttings, seeds and tissue culture. So, this review was presented to highlight on propagation of Jerusalem artichoke via in vivo and in vitro techniques

    Geophysical site assessment of an active urban development site, South Eastern Suburb of Cairo, Egypt

    Get PDF
    There has been significant structural damage of newly-built residential buildings in Quarter-27 District in the South of Cairo, Egypt. The proximity of an active limestone quarry may also be affecting ground stability. This paper shows how a near-surface geophysics survey could characterize the site, unusually after the initial housing construction had already been undertaken. Geophysical surveys included seismic refraction (acquired between phases of quarry blasting), electrical resistivity and ground penetrating radar 1D and 2D datasets. Geophysical results produced maps of a 3D ground model that also included water table depth, known major faults and a saturated layer that may have caused the building damage. ERT and GPR data was deemed optimal of the geophysical techniques trialled. This study shows that it is possible to undertake geophysical surveys to characterize a restricted urban site development

    Jerusalem artichoke (Helianthus tuberosus L.): A review of in vivo and in vitro propagation

    Get PDF
    Jerusalem artichoke (Helianthus tuberosus L.) is an old tuber crop with a recently renewed interest in multipurposeimprovement. It is a perennial tuberous plant rich in inulin and is a potential energy crop. During food shortages in times ofwar Jerusalem artichoke received more attention by scientists and farmers because of its multiple uses as a vegetable, medicinalplant, forage plant and source for biofuel. The energy crisis of the 1970s motivated research on Jerusalem artichoke forbiofuel as the aboveground plant biomass and the tubers can be used for this purpose. There are different methods to propagateJerusalem artichoke using tubers, rhizomes, slips (transplants derived from sprouted tubers), stem cuttings, seeds and tissueculture. So, this review was presented to highlight on propagation of Jerusalem artichoke via in vivo and in vitro techniques
    • …
    corecore