22 research outputs found

    Holocene volcanic soils in the Mt. Gambier region, South Australia

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    Volcanic soils derived from mid-Holocene basaltic tephra in the Mt. Gambier region of South Australia have developed in a xeric moisture regime. We studied two soils, one at Mt Gambier (MTG) and the other at nearby Mt Schank (MTS). Both volcanoes were active ca. 6000 cal. years ago. The MTG soil has a high content of CaCOā‚ƒ (incorporated during eruption through limestone) and other exotic materials intermixed with basaltic tephra containing low amounts of glass. The MTS soil is derived mainly from basaltic tephra with high glass content and much less CaCOā‚ƒ than at MTG. These parent mineralogies have led to markedly different clay compositions and chemical properties: the MTS soil contains abundant allophane (mainly) and ferrihydrite with few layer silicate clays, whereas the MTG soil is dominated by layer silicate clays and low allophane or ferrihydrite. Both soils are near neutral or alkaline. The MTS soil has a melanic horizon and andic properties and is classed as a Melanoxerand. The MTG soil has weak andic properties with insufficient glass to enable it to be classed in the Andisols, and is instead a Calcixeroll

    Selenate-enriched urea granules are a highly effective fertilizer for selenium biofortification of paddy rice grain

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    Citation: Premarathna, Lakmalie, Mike J. McLaughlin, Jason K. Kirby, Ganga M. Hettiarachchi, Samuel Stacey, and David J. Chittleborough. ā€œSelenate-Enriched Urea Granules Are a Highly Effective Fertilizer for Selenium Biofortification of Paddy Rice Grain.ā€ Journal of Agricultural and Food Chemistry 60, no. 23 (June 13, 2012): 6037ā€“44. https://doi.org/10.1021/jf3005788.We examined the effects of applied selenium (Se) species, time of application, method of application and soil water management regime on accumulation of Se in rice plants. Plants were grown to maturity in a temperature- and humidity-controlled growth chamber using three water management methods: field capacity (FC), submerged until harvest, and submerged and drained two weeks before harvest; two Se species: selenate (SeO[subscript 4] Ė‰Ā²) and selenite (SeO[subscript 3]Ė‰Ā²) applied at a rate equivalent to 30 g haĖ‰Ā¹; and four application methods: i) Se applied at soil preparation, ii) Se-enriched urea granules applied to floodwater at heading iii) foliar Se applied at heading and iv) fluid fertilizer Se applied to soil or floodwater at heading. Total Se concentrations in rice grains, husks, leaves, culms and roots were measured, as well as Se speciation in grains from the Se-enriched urea granule treatment. Highest Se concentrations in the grain occurred with SeO[subscript 4] Ė‰Ā² and with fertilizer applied at heading stage; SeO[subscript 4]Ė‰Ā²-enriched urea granules applied at heading increased grain Se concentrations 5 to 6 fold (by 450-600 Ī¼g kgĖ‰Ā¹) compared to the control (no fertilizer Se applied) in all water treatments. Under paddy conditions other Se fertilization strategies were much less effective. Drainage before harvesting caused Se to accumulate in/on rice roots, possibly through adsorption onto iron plaque on roots. Rice grains contained Se mainly in the organic form as selenomethionine (SeM) which comprised over 90 % of the total grain Se in treatments fertilized with SeO[subscript 4]Ė‰Ā² -enriched urea granules. The results of this study clearly show of the fertilizer strategies tested that biofortification of Se in rice grains can best be achieved in lowland rice by broadcast application of SeO[subscript 4]Ė‰Ā² -enriched urea granules to floodwater at heading stage

    Do people with risky behaviours participate in biomedical cohort studies?

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    BACKGROUND: Analysis was undertaken on data from randomly selected participants of a bio-medical cohort study to assess representativeness. The research hypotheses was that there was no difference in participation and non-participations in terms of health-related indicators (smoking, alcohol use, body mass index, physical activity, blood pressure and cholesterol readings and overall health status) and selected socio-demographics (age, sex, area of residence, education level, marital status and work status). METHODS: Randomly selected adults were recruited into a bio-medical representative cohort study based in the north western suburbs of the capital of South Australia ā€“ Adealide. Comparison data was obtained from cross-sectional surveys of randomly selected adults in the same age range and in the same region. The cohort participants were 4060 randomly selected adults (18+ years). RESULTS: There were no major differences between study participants and the comparison population in terms of current smoking status, body mass index, physical activity, overall health status and proportions with current high blood pressure and cholesterol readings. Significantly more people who reported a medium to very high alcohol risk participated in the study. There were some demographic differences with study participants more likely to be in the middle level of household income and education level. CONCLUSION: People with risky behaviours participated in this health study in the same proportions as people without these risk factors

    Applying an extended theoretical framework for data collection mode to health services research

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    <p>Abstract</p> <p>Background</p> <p>Over the last 30 years options for collecting self-reported data in health surveys and questionnaires have increased with technological advances. However, mode of data collection such as face-to-face interview or telephone interview can affect how individuals respond to questionnaires. This paper adapts a framework for understanding mode effects on response quality and applies it to a health research context.</p> <p>Discussion</p> <p>Data collection modes are distinguished by key features (whether the survey is self- or interviewer-administered, whether or not it is conducted by telephone, whether or not it is computerised, whether it is presented visually or aurally). Psychological appraisal of the survey request will initially entail factors such as the cognitive burden upon the respondent as well as more general considerations about participation. Subsequent psychological response processes will further determine how features of the data collection mode impact upon the quality of response provided. Additional antecedent factors which may further interact with the response generation process are also discussed. These include features of the construct being measured such as sensitivity, and of the respondent themselves (e.g. their socio-demographic characteristics). How features of this framework relate to health research is illustrated by example.</p> <p>Summary</p> <p>Mode features can affect response quality. Much existing evidence has a broad social sciences research base but is of importance to health research. Approaches to managing mode feature effects are discussed. Greater consideration must be given to how features of different data collection approaches affect response from participants in studies. Study reports should better clarify such features rather than rely upon global descriptions of data collection mode.</p

    Living with diabetes: rationale, study design and baseline characteristics for an Australian prospective cohort study

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    Background: Diabetes mellitus is a major global public health threat. In Australia, as elsewhere, it is responsible for a sizeable portion of the overall burden of disease, and significant costs. The psychological and social impact of diabetes on individuals with the disease can be severe, and if not adequately addressed, can lead to the worsening of the overall disease picture. The Living With Diabetes Study aims to contribute to a holistic understanding of the psychological and social aspects of diabetes mellitus

    Predictors of positive and negative parenting behaviours: evidence from the ALSPAC cohort

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    Background This study aimed to establish the predictors of positive and negative parenting behaviours in a United Kingdom population. The majority of previous research has focused on specific risk factors and has used a variety of outcome measures. This study used a single assessment of parenting behaviours and started with a wide range of potential pre- and post-natal variables; such an approach might be used to identify families who might benefit from parenting interventions. Methods Using a case-control subsample of 160 subjects from the Avon Longitudinal Study of Parents and Children (ALSPAC), regression analysis was undertaken to model parenting behaviours at 12 months as measured by the Mellow Parenting Observational System. Results Positive parenting increased with maternal age at delivery, levels of education and with prenatal anxiety. More negative interactions were observed among younger mothers, mothers with male infants, with prenatal non-smokers and among mothers who perceived they had a poor support structure. Conclusions This study indicates two factors which may be important in identifying families most at risk of negative parenting: younger maternal age at delivery and lack of social support during pregnancy. Such factors could be taken into account when planning provision of services such as parenting interventions. We also established that male children were significantly more likely to be negatively parented, a novel finding which may suggest an area for future research. However the findings have to be accepted cautiously and have to be replicated, as the measures used do not have established psychometric validity and reliability data

    Identifying cost-effective reforestation approaches for biodiversity conservation and carbon sequestration in the Australian tropics

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    There is great potential for rainforest reforestation to help with biodiversity conservation and climate change mitigation. This project aims to determine the reforestation approach that maximises native biodiversity, while profiting from the carbon market. We use a replicated experimental design to track the biodiversity, carbon value and costs associated with eight different approaches of reforestation of cattle pasture into secondary rainforest. We are monitoring several key taxa (plants, butterflies, dung beetles, bees and ants) and carbon pools, prior to reforestation and throughout the regeneration process. The fieldwork is conducted in North Queensland, Australia

    Correct interpretation of chemical diagrams requires transforming from one level of representation to another

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    17 volunteer non-major chemistry students taking an introductory university chemistry course were interviewed about their understanding of a variety of chemical diagrams. All the students\u27 interviewed appreciated that diagrams of laboratory equipment were useful to show how to set up laboratory equipment. However students\u27 ability to explain specific diagrams at either the macroscopic or sub-microscopic level varied greatly. The results highlighted the poor level of understanding that some students had even after completing both exercises and experiments using the diagrams. The connection between the diagrams of the macroscopic level (equipment, chemicals), the sub- microscopic level (molecular) and the symbolic level (equations) was not always considered explicitly by students. The results indicate a need for chemical diagrams to be used carefully and more explicitly to ensure learner understanding. Correspondingly, students need to interpret visual chemical diagrams using meta-visualisation skills linking the various levels of representation, and appreciating the role of the diagrams in explanations need to be developed.<br /

    Rethinking and rescoring the SF-12

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    Objectives: To derive and assess the validity of an Australian version of the SF-12 quality-of-life questionnaire. Methods: Using regression methods and structural equation modelling to obtain item weights, an Australian version of the SF-12 was derived from Australian population survey data and compared to the existing United States (US) SF-12 variable set. Results: The Australian version of the SF-12 explained 94% of the variation for physical components summary (PCS) and the mental components summary (MCS) of the SF-36 questionnaire. There was high level of agreement on the MCS and PCS summary scores between both versions of the SF-12 and the SF-36. Conclusions: Although it is possible to derive a valid Australian version of the SF-12 it is concluded the US version of the SF-12 be used for reasons of international comparability, but using item weights derived from structural equation modelling.David Wilson, Graeme Tucker, Catherine Chittleboroug
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