Minerva Elements Records
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ItemMolecularly isolated perylene diimides enable both strong exciton-photon coupling and high photoluminescence quantum yield(Royal Society of Chemistry, 2019-03-14)Strong coupling in organic media holds the promise of efficient room temperature polariton lasing with solution-processed materials. Currently, however, only five pure-organic materials have been shown to demonstrate polariton lasing. A major challenge is to achieve high exciton–photon coupling while maintaining high photoluminescence quantum yield. Here, we utilize a series of diimide perylene materials that possess sterically hindered substituents, dispersed within a polymer matrix. The rigid structures prevent aggregation and allow high photoluminescence quantum yield (PLQY) at large dye loadings. We demonstrate that these systems can exhibit substantial Rabi splittings at dye loadings that yield film PLQYs of up to 85%, making these perylene derivatives promising materials for polariton lasers.
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ItemHighly Efficient Luminescent Solar Concentrators by Selective Alignment of Donor-Emitter Fluorophores(AMER CHEMICAL SOC, 2019-04-23)Vertically aligning fluorophores to the surface of a waveguide is known to be an effective approach to improve the optical quantum efficiency (OQE) of luminescent solar concentrators (LSCs). While the chromophore alignment assists waveguiding of the emitted photons to the LSC edges, it also significantly reduces the light-harvesting properties of the LSC. We report here a fluorophore pair consisting of a sphere-shaped energy donor and a rod-shaped emitter that was incorporated in LSCs to provide selective fluorophore alignment to address the reduced incident-light absorption issue. A liquid-crystal polymer matrix was used to perpendicularly align the rod-shaped acceptors to a favorable orientation for light guiding, while the sphere-shaped donor was randomly oriented to maintain its light-absorbing properties. The OQE of LSC devices with this selectively aligned donor-acceptor fluorophore system is 78% without significant loss of light-harvesting capability.
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ItemTetrabenzo[5.7]fulvalene: a forgotten aggregation induced-emission luminogen(ROYAL SOC CHEMISTRY, 2019-10-04)Tetrabenzo[5.7]fulvalene, one of the first recognized stable members of mixed fulvalenes, has attracted widespread interest for its remarkable structure. However, little has been known about its photoactivity, most likely owing to its very weak luminescence in the solution state. Here we show for the first time that this compound exhibits aggregation-induced emission (AIE) properties. Its photoluminescence and X-ray crystal structure reveal an interesting mechanism of the AIE phenomenon.
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ItemIntramolecular Versus Intermolecular Triplet Fusion in Multichromophoric Photochemical Upconversion(AMER CHEMICAL SOC, 2019-08-22)Photon upconversion is a process that creates high-energy photons under low photon energy excitation. The effect of molecular geometry on the triplet fusion upconversion process has been investigated in this work through the design and synthesis of four new 9,10-diphenylanthracene (DPA) derivatives by employing platinum octaethylporphyrin as the triplet sensitizer. These new emitter molecules containing multiple DPA subunits linked together via a central benzene core exhibit high fluorescence quantum yields. Interestingly, large differences in the triplet fusion upconversion performance were observed between the derivatives with the meta-substituted dimer showing the closest performance to the DPA reference. The differences are discussed in terms of the statistical probability for obtaining a high-energy singlet excited state from triplet fusion, f, for both inter- and intramolecular processes and the effect of magnetic field on the upconversion efficiency. These results demonstrate the challenges to be overcome in improving triplet fusion upconversion efficiency based on multichromophoric emitter systems.
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ItemDegradation profiles of silk textiles in diverse environments: Synchrotron based infrared micro-spectroscopy analysis(Springer, 2017)In this paper, synchrotron based infrared micro-spectroscopy was utilized to describe the degradation profile of fibroin contained in silk textiles (Bombyx mori). The spatial distributions of deterioration effects in silk samples artificially aged at an assortment of conditions (thermal, hydrolytic and ultraviolet) were distinctly visualised and in accordance with the findings from conventional infrared spectroscopy in references. Further this method was applied on a historic sample from a private collection in Melbourne, and presented consistent results. This established synchrotron IR chemical mapping method could enable museum professionals to better understand the preservation state of historic silk and make informed decisions for conservation.
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ItemEpigenetic Changes in Diabetes and Cardiovascular Risk(LIPPINCOTT WILLIAMS & WILKINS, 2016-05-27)Cardiovascular complications remain the leading causes of morbidity and premature mortality in patients with diabetes mellitus. Studies in humans and preclinical models demonstrate lasting gene expression changes in the vasculopathies initiated by previous exposure to high glucose concentrations and the associated overproduction of reactive oxygen species. The molecular signatures of chromatin architectures that sensitize the genome to these and other cardiometabolic risk factors of the diabetic milieu are increasingly implicated in the biological memory underlying cardiovascular complications and now widely considered as promising therapeutic targets. Atherosclerosis is a complex heterocellular disease where the contributing cell types possess distinct epigenomes shaping diverse gene expression. Although the extent that pathological chromatin changes can be manipulated in human cardiovascular disease remains to be established, the clinical applicability of epigenetic interventions will be greatly advanced by a deeper understanding of the cell type-specific roles played by writers, erasers, and readers of chromatin modifications in the diabetic vasculature. This review details a current perspective of epigenetic mechanisms of macrovascular disease in diabetes mellitus and highlights recent key descriptions of chromatinized changes associated with persistent gene expression in endothelial, smooth muscle, and circulating immune cells relevant to atherosclerosis. Furthermore, we discuss the challenges associated with pharmacological targeting of epigenetic networks to correct abnormal or deregulated gene expression as a strategy to alleviate the clinical burden of diabetic cardiovascular disease.
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ItemCultural precedents for the repatriation of legacy song records to communities of origin(Australian Institute of Aboriginal Studies, 2016-01-01)Repatriation of song recordings from archives and private collections to communities of origin is both a common research method and the subject of critical discourse. In Australia it is a priority of many individual researchers and collecting institutions to enable families and cultural heritage communities to access recorded collections. Anecdotal and documented accounts describe benefits of this access. However, digital heritage items and the metadata that guide their discovery and use circulate in complex milieus of use and guardianship that evolve over time in relation to social, personal, economic and technological contexts. Ethnomusicologists, digital humanists and anthropologists have asked, what is the potential for digital items, and the content management systems through which they are often disseminated, to complicate the benefits of repatriation? How do the 'returns' from archives address or further complicate colonial assumptions about the value of research? This paper lays the groundwork for consideration of these questions in terms of cultural precedents for repatriation of song records in the Kimberley. Drawing primarily on dialogues between ethnomusicologist Sally Treloyn and senior Ngarinyin and Wunambal elder and singer Matthew Dembal Martin, the interplay of archival discovery, repatriation and dissemination, on the one hand, and song conception, song transmission, and the Law and ethos of Wurnan sharing, on the other, is examined. The paper provides a case for support for repatriation initiatives and for consideration of the critical perspectives of cultural heritage stakeholders on research transactions of the past and in the present.
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ItemTeacher-Mediated Interventions to Support Child Mental Health Following a Disaster: A Systematic Review.(Public Library of Science (PLoS), 2015-12-08)OBJECTIVES: This review sought to identify, describe and assess the effectiveness of teacher-mediated interventions that aim to support child and adolescent recovery after a natural or man-made disaster. We also aimed to assess intervention applicability to rural and remote Australian school settings. METHOD: A systematic search of the academic literature was undertaken utilising six electronic databases (EBSCO, Medline, PsycINFO, Embase, ERIC and CINAHL) using terms that relate to: teacher-mediated and school-based interventions; children and adolescents; mental health and wellbeing; natural disasters and man-made disasters. This was supplemented by a grey literature search. RESULTS: A total of 20 articles reporting on 18 separate interventions were identified. Nine separate interventions had been evaluated using methodologically adequate research designs, with findings suggesting at least short-term improvement in student wellbeing outcomes and academic performance. CONCLUSIONS: Although none of the identified studies reported on Australian-based interventions, international interventions could be adapted to the Australian rural and remote context using existing psychosocial programs and resources available online to Australian schools. Future research should investigate the acceptability, feasibility and effectiveness of implementing interventions modelled on the identified studies in Australian schools settings.
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ItemCultural responses to the migration of the barn swallow in Europe(ANU Press, 2019-05-09)This paper investigates the place of barn swallows in European folklore and science from the Bronze Age to the nineteenth century. It takes the swallow’s natural migratory patterns as a starting point, and investigates how different cultural groups across this period have responded to the bird’s departure in autumn and its subsequent return every spring. While my analysis is focused on classical European texts, including scientifc and theological writings, I have also considered the swallow’s representation in art. The aim of this article is to build a longue durée account of how beliefs about the swallow have evolved over time, even as the bird’s migratory patterns have remained the same. As I argue, the influence of classical texts on medieval and Renaissance thought in Europe allows us to consider a temporal progression (and sometimes regression) in the way barn swallow migration was explained and understood.
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ItemNo Preview AvailableXBRL and the qualitative characteristics of useful financial information(Emerald, 2017-05-02)Purpose: eXtensible Business Reporting Language (XBRL) is an internet-based interactive form of reporting language that is expected to enhance the usefulness of financial reporting (Yuan and Wang, 2009). In the UK and the USA, XBRL is mandatory, and in Australia, it is voluntarily adopted. It has been reported that in the not too distant future, XBRL will be the standard format for the preparation and exchange of business reports (Gettler, 2015). Using an experimental approach, this study assesses the usefulness of financial reports with XBRL tagged information compared to PDF format information for non-professional investors. The authors investigate participants’ perceptions of usefulness in relation to the qualitative characteristics of relevance, understandability and comparability. Design/methodology/approach: This paper uses an experimental approach featuring a profit-forecasting task to determine if participants perceive XBRL-tagged information to be more useful compared to PDF-formatted information. Findings: Results reveal that financial information presented with XBRL tagging is significantly more relevant, understandable and comparable to non-professional investors. Originality/value: The authors address a gap in the literature by examining XBRL usefulness in Australia where XBRL adoption will be mandated within the not too distant future. Currently, the voluntary adoption of XBRL by preparers and users is low, possibly, because of a lack of awareness about XBRL and its potential benefits. This study yields significant implications for the accounting regulators in creating more awareness on the benefits of using XBRL and to create an impetus for XBRL adoption.