21 research outputs found

    CdTe quantum dots precipitation of monodisperse fractions from colloid solutions

    Get PDF
    Abstract. CdTe nanocrystals were prepared in aqueous solution by the reaction between Cd 2+ and H 2 Te, obtained electrochemically in a galvanostatic cell, in the presence of thioglycolic acid. Subsequently, we have investigated precipitation of monodisperse fractions of CdTe quantum dots from polydisperse colloid solutions. In addition, the photoluminescence characteristics of these systems were studied in detail

    Poor adherence to antibiotic prescribing guidelines in acute otitis media—obstacles, implications, and possible solutions

    Get PDF
    Many countries now have guidelines on the clinical management of acute otitis media. In almost all, the public health goal of containing acquired resistance in bacteria through reduced antibiotic prescribing is the main aim and basis for recommendations. Despite some partial short-term successes, clinical activity databases and opinion surveys suggest that such restrictive guidelines are not followed closely, so this aim is not achieved. Radical new solutions are needed to tackle irrationalities in healthcare systems which set the short-term physician–patient relationship against long-term public health. Resolving this opposition will require comprehensive policy appraisal and co-ordinated actions at many levels, not just dissemination of evidence and promotion of guidelines. The inappropriate clinical rationales that underpin non-compliance with guidelines can be questioned by evidence, but also need specific developments promoting alternative solutions, within a framework of whole-system thinking. Promising developments would be (a) physician training modules on age-appropriate analgesia and on detection plus referral of rare complications like mastoiditis, and (b) vaccination against the most common and serious bacterial pathogens

    Photoluminescent Properties of CdTe Nanocrystals in Colloidal Solutions and Polymer Films

    No full text
    Using stabilizers and promoters we have obtained colloidal CdTe nanocrystals (NCs) in aqueous solutions. Incorporation of the CdTe NCs into polymer films has been fulfilled subsequently. It is shown that the use of vinyl acetate-acrylate copolymer as the matrix material for CdTe NC incorporation from colloidal solutions allows to get stable and nontoxic nanoheterogeneous film structures, which are characterized by satisfactory values of the photoluminescence quantum yield. Photoluminescence characteristics of the studied materials have been analyzed. Keywords: cadmium telluride, nanocrystal, vinyl acetate-acrylate copolymer, photoluminescence spectra, photoluminescence quantum yield.</p

    Using systems thinking and the Intervention Level Framework to analyse public health planning for complex problems: Otitis media in Aboriginal and Torres Strait Islander children

    No full text
    Middle ear disease (otitis media) is endemic among Aboriginal and Torres Strait Islander children in Australia and represents an important cause of hearing loss. The disease is the result of a mix of biological, environmental and host risk factors that interact in complex, non-linear ways along a dynamic continuum. As such, it is generally recognised that a holistic, systems approach is required to reverse the high rates of otitis media in Aboriginal and Torres Strait Islander children. The objective of this paper is to examine the alignment between efforts designed to address otitis media in Aboriginal and Torres Strait Islander children in Queensland, Australia and core concepts of systems thinking. This paper's overall purpose is to identify which combination of activities, and at which level, hold the potential to facilitate systems changes to better support ear health among Aboriginal and Torres Strait Islander children.We began with a review of documents identified in consultation with stakeholders and an online search. In addition, key informants were invited to participate in an online survey and a face-to-face or phone interview. Qualitative interviews using a semi-structured interview guide were used to explore survey responses in more depth. We also undertook interviews at the community level to elicit a diverse range of views. Ideas, statements or activities reported in the documents and interviews as being performed under the Intervention Level Framework were identified using qualitative thematic and content analysis. A quantitative descriptive analysis was also undertaken, whereby data was extracted into an Excel spreadsheet and coded under the relevant strategic directions and performance indicators of the Framework. Subsequently, we coded activities against the five-level intervention framework developed by Malhi and colleagues, that is: 1) paradigm; 2) goals; 3) system structure; 4) feedback and delays; and 5) structural elements.Overall, twenty documents were reviewed. We examined surveys and interviews with six key informants. Twenty-four individual and 3 group interviews were conducted across central and community level informants. One hundred and four items were coded from the 20 documents and 156 items from interview data. For both data sets, the majority of activities were coded at the structural elements level. The results suggested three key areas where further work is needed to drive sustained improvements: 1) build the governance structures needed for paradigm shift to achieve a multi-sectoral approach; 2) develop shared system level goals; 3) develop system-wide feedback processes.Sustained progress in improving ear health within Aboriginal and Torres Strait Islander children requires a holistic, system-wide approach. To advance such work, governance structures for multi-sectoral collaboration including the development of joint goals and monitoring and feedback are required. Intervening at these higher leverage points could have a profound effect on persistent public health issues

    Glucocorticoid Receptor Homodimers and Glucocorticoid-Mineralocorticoid Receptor Heterodimers Form in the Cytoplasm through Alternative Dimerization Interfaces

    No full text
    Steroid hormone receptors act to regulate specific gene transcription primarily as steroid-specific dimers bound to palindromic DNA response elements. DNA-dependent dimerization contacts mediated between the receptor DNA binding domains stabilize DNA binding. Additionally, some steroid receptors dimerize prior to their arrival on DNA through interactions mediated through the receptor ligand binding domain. In this report, we describe the steroid-induced homomeric interaction of the rat glucocorticoid receptor (GR) in solution in vivo. Our results demonstrate that GR interacts in solution at least as a dimer, and we have delimited this interaction to a novel interface within the hinge region of GR that appears to be both necessary and sufficient for direct binding. Strikingly, we also demonstrate an interaction between GR and the mineralocorticoid receptor in solution in vivo that is dependent on the ligand binding domain of GR alone and is separable from homodimerization of the glucocorticoid receptor. These results indicate that functional interactions between the glucocorticoid and mineralocorticoid receptors in activating specific gene transcription are probably more complex than has been previously appreciated
    corecore