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Breaking the Circuit of Information Poverty: Early Warning Messages and DHH Communities in Vietnam
No full textPeople regardless of their abilities may face the ramifications of natural
disasters. However, disaster communications often ignore the lived experience
of people with disabilities. Early warning communications, which can better
prepare people for disasters, are not the exception. The design and delivery of
early warning communications are often auditory, excluding the lived
experience of the Deaf and Hard of Hearing (DHH) individuals. While studies
intersecting disaster and disabilities have gained traction, attention given to
the DHH remains limited. Through interviews and group discussions with Deaf
organizations and DHH individuals in Vietnam, this study found a range of
grassroots efforts that the DHH performed when the early warning and
disaster communications were exclusionary. It documented the roots of
disaster-related information poverty within the DHH communities and their
agency to overcome it such as co-creating inclusive content with trustworthy
others and hearing people. The findings potentially inform early warning
message designers and disaster communication programmers to better
incorporate the DHH lived experience to disaster management plans.</p
Current outlook on sustainable feedstocks and processes for sustainable aviation fuel production
No full textChallenges related to economic viability and production processes to sustainable aviation fuel (SAF) have significantly hindered its widespread commercial adaptations. This mini review provides the current opinion on various feedstocks and conversion processes for low-cost SAF production. The primary emphasis lies on exploring alternatives to traditional feed crops with a shift toward utilizing lignocellulosic biomass, waste feedstocks, oil-seed crops, and microalgal oil. The Fischer–Tropsch process, hydroprocessed esters and fatty acids, and nonthermal plasma method, where lignocellulosic biomass, oil-based crops, microalgal oil, and waste oils are widely used are cost effective, have high potential to produce SAF. However, technical immaturity and high cost compel detailed investigation on the optimization process using various alternative feedstock. This mini review insights the critical factors effecting reaction efficiencies, including feedstock characteristics, reaction parameters, catalyst reusability, and supports that need systematic investigation. Conclusively, this outlook delves into the challenges, solutions, and opportunities associated to cost-effective SAF production.</p
Conveying COVID-19 Health Information with CALD Social Media Influencers: The Cultural Role of Brand Consistency and Relatability for Identity Authenticity
No full textDuring the COVID-19 global pandemic, young people and culturally and linguistically diverse populations (CALD) were underserved by non-tailored government health messaging. Social media influencers offer a potentially cost-effective and scalable form of health communication for reaching young CALD populations. Little is known, however, about the characteristics of an influencer’s identity authenticity for reaching CALD youth, or how that authenticity is underpinned by brand consistency and relatability. Drawing on the authors’ commissioned evaluation of a state government initiative for delivering targeted COVID-19 health information to CALD young people (11-26 years) in Victoria, Australia, this paper analyses findings from thirteen qualitative interviews with influencers and target audience members to provide insights on identity authenticity in the contemporary digital ecology. The analysis aims to contribute to the limited extant knowledge of the role third-party influencers can play in government health communication by providing a cultural context for understanding identity authenticity when targeting minority social groups.</p
Low Viscosity Precursors of Polyether Ketone Ketone, Their in situ Polymerisation and Application to Composite Formation
No full textThe aerospace industry is in a period of transition, as new materials and methods of manufacturing are sought to address the global challenges of climate change and carbon emissions. As a part of this transition, traditional metal structures are increasingly being replaced by carbon fibre reinforced composite materials. Currently composite materials in aerospace are largely comprised of thermosets with low viscosity precursors allowing for high throughput manufacturing. These are limited by being brittle, irreparable without replacement and unable to be recycled; an increasing concern as their adoption grows.
A polymer that can address these concerns is PolyEther Ketone Ketone (PEKK), an ultra-high-performance thermoplastic. Commonly used as a matrix with carbon fibre, it is lightweight with exceptional material properties and chemical resistance. In addition to this PEKK is inherently recyclable and sees use in various aerospace parts. The properties of the PEKK polymer can also be fine-tuned by altering the backbone with different structural isomers resulting from para-substituted terephthaloyl chloride and meta-substituted isophthaloyl chloride starting materials, with this ratio of para to meta links being known as the T/I ratio. Adversely, PEKK’s usefulness as a composite matrix is limited by its high viscosity in the melt. As PEKK’s current predominant synthesis requires that the polymer must be melted before use, a method by which PEKK composites could be produced from a low viscosity resin would be ideal.
One method that could produce PEKK from low viscosity precursors is entropy driven ring-opening polymerisation (ED-ROP). ED-ROP occurs through the ring-opening of large, strainless, low viscosity ring structures known as macrocyclic oligomers (MCOs). Driven by the increased conformational entropy of the linear polymer, polymerisation occurs without the release of heat, volatiles or by-products. ED-ROP is therefore well suited to the production of composites by an in situ polymerisation, where low viscosity PEKK MCOs could be injected into a mould, wet-out the fibres, and polymerise without contamination or voids in the finished part. Such a process could provide high-throughput manufacturing options. Accordingly, the research proposed for this PhD project was to synthesise MCOs of PEKK, to polymerise them via an in situ ED-ROP with methods analogous to resin infusion, and investigate their interaction with carbon fibre.
A review of the literature found no complete examples of a PEKK MCO, and hence no examples of their ED-ROP nor composite formation with reinforcing fibres such as carbon fibre (CF). Examples from the broader family of polyaryl ether ketones (PAEKs) have been explored however and were informative for MCO synthesis conditions, as well as the mechanics, conditions and initiators used for this type of polymerisation. In addition, the properties of the PEKK polymer, such as crystallinity and thermal characteristics, the use of sizings for PEKK/CF composites and the effects of para and meta structural isomers on the polymer’s properties, were also examined.
From this review experimentation began with the pseudo-high dilution synthesis of polyether ketone (PEK) to assess reaction set-up and conditions. This approach was then applied to produce novel MCOs of the homopolymers m PEKK and p PEKK in good yields, with optimisation experiments finding that caesium carbonate and enhanced removal of water improved the yields of cyclic species. Characterisation by Nuclear Magnetic Resonance (NMR) spectroscopy, Matrix-Assisted Laser Desorption/Ionisation Time of Flight (MALDI-ToF) mass spectrometry and Gel Permeation Chromatography (GPC) was required to distinguish between the MCOs and linear polymer, due to their structural similarities. Dimer species of two homopolymer MCOs were also successfully isolated, crystallised and analysed by X-ray crystallography to prove the cyclic structure. Attempts to further optimise the reaction conditions by a high-throughput assessment utilising Rapid Automated Materials Processing (RAMP) proved unsuccessful. Despite this, the synthesis was also expanded to produce novel MCOs of PEKK with three T/I ratios related to those of commercial PEKK products. NMR spectroscopy of both these MCOs and a commercial 60/40 T/I PEKK showed good agreement.
These novel MCOs were then polymerised by ED ROP. Polymerisations were carried out in a (Differential Scanning Calorimetry) DSC instrument with conditions analogous to an in situ polymerisation, and the successful formation of polymers determined by the appearance of a glass transition as well as changes to the morphology and solubility of the material. Glass transitions for both PEKK homopolymers and the three T/I ratio grades were identified and showed good agreement with a commercial sample, and further polymerisation aspects investigated. ThermoGravimetric Analysis (TGA) was used to show no weight loss during polymerisation, as should be expected of an ED-ROP. TGA was also employed to investigate the properties of the purified PEKK MCO dimers, as PAEK dimers had been noted in literature to impair ED-ROP.
Due to the insolubility of the PEKK polymer and its structural similarity to the MCOs comprehensive examination of the polymerisation proved difficult. Further analysis by GPC was therefore sought to determine the degree of polymerisation, and a thioketalisation strategy from literature was needed to ensure the solubility of the PEKK. This strategy was tested against the commercial sample and the MCOs, and the full derivatisation confirmed by NMR spectroscopy. Polymerisation experiments were conducted to identify optimal ED-ROP conditions with regards to temperature, time, type and amount of initiator, and type of PEKK MCO. Some indication of ring-opening polymerisation had occurred, but high molecular weight polymerisation could not be confirmed. The deleterious effects from the presence of oxygen and water were identified as a potential cause for this, along with possible impairment from the presence of the MCO dimer. Polymerisation was then with a neat sample of m-PEKK MCOs, with the dimer removed and 2 mol% Caesium Fluoride (CsF) initiator, under high vacuum conditions. The resultant polymer was thioketalised, analysed by GPC and, once corrected for the derivatisation, displayed a successful high molecular weight polymerisation, with a Mn of 22,000 g/mol and a Mw of 38,000 g/mol, the first example of a high molecular weight PEKK polymer formed by the ED-ROP of MCOs. Subsequent experiments under low vacuum also showed some evidence of ED-ROP on GPC but did not achieve the same molecular weights.
Formation of test composites of PEKK/CF by in situ polymerisation was also examined. Analysis was tailored to properties highly important to composite structures that could be assessed on a small scale. The viscosity of the MCOs was examined, and the melt complex viscosity found to be significantly lower than that of PEKK polymer. Test composites were then formed by in situ ED-ROP under low vacuum, being the first example of a PEKK/CF composite formed by ED-ROP. The samples were assessed by Scanning Electron Microscopy (SEM), with it being observed that the polymer had thoroughly penetrated the carbon fibre tow and wetted out the fibres. Cryofracturing of the composite samples revealed a close interphase between the fibre and matrix with no visible voids. Recovery and analysis of the PEKK showed a glass transition similar to those previously observed. GPC analysis, using the thioketalisation methods discussed, revealed that polymerisation had taken place but did not display a high molecular weight polymer.</p
Actual Places: The Transformative Nature of Experiential and Reflective Learning
No full textIdentity-based discrimination resulting from intercommunity conflict has the potential to produce biased attitudes toward those outside of the group, creating a division between communities, with individuals becoming more entrenched in their identity-grounded beliefs. This chapter highlights the significance of experiential and reflective learning in grassroots interventions designed to promote peacebuilding in communities affected by conflicts that lead to ethnic segregation. The argument is that, by actively engaging with places and people, program participants can develop new perspectives and stories, stimulating transformative learning. In addition to experiential learning, peacebuilding education initiatives (PEIs) utilize various other methods of reflection and critical thinking to challenge the participants’ existing beliefs and values, desiring to aid in the modification or restructuring of their cognitive framework. The chapter also suggests that visiting places and reflecting on experiences can promote reconciliation and foster a more inclusive civic identity among participants.</p
Making Place: Mediated Attention in Expanded Landscape Photography
No full textMaking Place is a series of point clouds as expressions from my correspondence with the Maribyrnong River and volumetric imaging technology. The work responds to a sense of becoming within place and photography.
The research investigates the entanglements of practitioner, environment, and technology in expanded landscape photography. Through a creative practice-based approach, it examines how photo imaging tools mediate my attention to the landscape and how experimental interventions generate new ways of performing, discovering, and perceiving it. The research generates a methodology that renegotiates the relations between practitioner, landscape, and technology by treating them as co-constituting correspondents, offering a non-representational strategy that explores new vectors of making and critique within expanded landscape photography.
While a mutual unfolding of attention and practice is established in mediation theory, it remains underexplored in a creative photography context. By disrupting my existing landscape photography practice and incorporating photogrammetry, this research extends mediation theory by developing an original series of point cloud artworks through a novel and productive creative methodology for making place.</p
Silicon-based Optical Switch using Phase-change Materials
No full textRecently, silicon integrated optical circuits have attracted intensive interests, thanks to the compatibility with the CMOS technology that enables mass production at low cost. The optical switch is an essential part of optical integrated circuits, with broad applications in optical communications and networks, optical computing, and sensing such as LiDAR. In general, the silicon integrated optical switch adopts thermo-optic or carrier dispersion effect to realize reconfigurable signal routing. However, the use of thermo-optic effect leads to high power consumption, and the carrier dispersion effect has the disadvantage of small refractive index change. In addition, both effects are non-latching, and hence, continuous power consumption is required even when switching is not needed. For overcoming these drawbacks, phase-change materials (PCMs) have been introduced into silicon integrated optical switches. However, prior works either had too small bandwidth, too high loss, too large size, or too few output ports, only two or even one. In this work, we first proposed a silicon-based optical switch with GST-enabled phase-shifting region. This optical switch is based on contra-directional couplers composed of two phase-shifted Bragg gratings. To minimize the impact of GST absorption loss, GST is only used in the phaseshifting area, and the switching function is achieved by changing the state of GST. Results show that the proposed device has a 3 dB operation bandwidth of about 163.2 GHz (1.394 nm) and an extinction ratio of about 19.06 dB for the drop port and about 20.25 dB for the through port. The loss at the central operation wavelength is about 1.3 dB and 1.04 dB for the through port and the drop port, respectively, and the largest loss over the entire operation bandwidth for these two ports is 1.66 dB and 2.35 dB. Furthermore, the optical switch is shown to be bi-directional, achieving similar performances when light propagates in the opposite direction. Compared with previous works, the proposed optical switch realizes wider operation bandwidth, higher extinction ratio and lower loss. After that, we proposed and studied a silicon-based optical switch based on the contra-directional coupler structure using Sb2Se3. The optical switch is non-volatile because of the material properties of Sb2Se3, and thanks to the property of Sb2Se3 that extremely low loss in both states over the entire C-band, this device has low loss. Results have shown that the proposed optical switch has a 3 dB operation bandwidth of 353 GHz (3.045 nm), and an extinction ratio of 26.9 dB and 14.7 dB for the through port and the drop port, respectively. The proposed optical switch has also demonstrated a low insertion loss, which is about 0.52 dB at the through port and about 1.03 dB at the drop port. In addition, we further proposed and studied the 1×3 optical switch based on the contra-directional coupler structure using Sb2Se3. Compared with conventional optical switches that have 2n ports, the proposed device enhanced the flexibility on the number of output ports to achieve more efficient operations. This optical switch also leverages the non-volatile extremely low loss material properties of Sb2Se3. Simulation results indicate that the proposed optical switch has an operation bandwidth of about 237 GHz (2.05 nm), with an extinction ratio of 14.3 dB for the through port and approximately 14.8 dB for the upper/lower drop ports. Additionally, the optical switch has shown an insertion loss of about 0.3 dB at the through port and about 1.3 dB at the upper/lower drop ports. Then, we proposed and studied a silicon-based 1×3 optical switch with a non-contact phase change control mechanism using Sb2Se3. Different from the previous work, this device can work with other materials with higher material loss in principle, although needs optimization for sure, but this is a good advantage. Moreover, its fabrication is less challenging, as the phase change materials is on sides. Results indicate that the proposed optical switch has an operation bandwidth of 96.6 GHz (0.8 nm), together with an extinction ratio of 13.1 dB for the through port and approximately 21.5 dB for the upper/lower drop ports. Additionally, the optical switch has shown an insertion loss of around 3.4 dB for the through port and the upper/lower drop ports.</p
Ephemeral mapping of changing perception of place through creative practice
No full textOne's perception of place is in constant flux, shaped by experience, memories, and feelings over time. Time and perception of place are inextricably linked, where the transient nature of time and one's perception of place affects one's understanding of the world. This transience challenges cartography. This paper reports on the outcomes of a year-long mapping project (A Walk in the Park), where the effects of time on perception of place could be seen through recording personal experiences of being in the park. The outcomes of these experiences were used to develop a new model of reflective practice which is called the Interdisciplinary Model of Creative Practice. This model and an accompanying tool, the brief, was employed to create ephemeral mapping prototypes from records of my experiences and ideas about time and perception of place from the scholarly literature. The model builds a creative mapping process by drawing from and weaving together the perspectives of scientific cartography, design, and artistic expression. Using the example of ephemeral mapping, this paper shows how one can use this Interdisciplinary Model of Creative Practice, describing the approach for other researchers, cartographers, designers, or artists who might utilise the model and tools offered in this paper for their own creative practice.</p
Nature-based social interventions for people experiencing loneliness: the rationale and overview of the RECETAS project
No full textLoneliness is a major social concern with health consequences worldwide for populations across different demographic, cultural, social, economic, geographic, and environmental contexts. In March 2021, we launched Horizon 2020 European Commission-funded project, ‘Reimagining Environments for Connection and Engagement: Testing Actions for Social Prescribing in Natural Spaces (RECETAS)’ to reduce loneliness and promote health-related quality of life. In this paper, we present the project logic model, informed by stakeholder input, that aims to guide the initiative from its design and implementation to its evaluation in six cities across three continents, including Europe (Barcelona, Helsinki, Marseille, Prague), Australia (Melbourne), and South America (Cuenca). This model is being used to guide the implementation and evaluation of nature-based social prescribing interventions. Process and outcome measures will be used to compare outcomes in different settings and population contexts. The use of a logic model with stakeholder input ensures that the interventions are responsive to local needs, sustainable, and transferable to other geographic, social, economic, and cultural contexts. Knowledge translation will be central to maximising impacts on population health, civil society, and health and social systems in urban areas.</p
Connecting through nature: A systematic review of the effectiveness of nature-based social prescribing practices to combat loneliness
No full textLoneliness is increasingly recognized as an urgent public health issue due to its impact on mental and physical health, and well-being. Yet, we lack comprehensive, proven strategies for confronting this global problem. There is evidence that contact with nature and greenspace reduces loneliness by facilitating belonging, social connections, and social cohesion. This review aimed to explore whether such positive outcomes can be enhanced via group-based interventions in nature. We used a mixed-methods systematic review approach to evaluate and characterize literature on nature-based social interventions for their effectiveness in reducing loneliness. We included all age groups, in populations with or without reported health problems. Using the Mixed Methods Appraisal Tool, we assessed the quality of included qualitative, quantitative and mixed methods studies. The 38 studies identified describe a wide variety of interventions and target groups. The quantitative studies included mostly small sample sizes with small or moderate effects. The qualitative studies, however, showed more clearly that these interventions can reduce loneliness. Group-based activities including natural elements cultivated connectedness and belonging, which are key mechanisms to reducing loneliness. Specifically, longer interventions showed greater promise. Policy and practice recommendations include loneliness screening, the need to describe loneliness more precisely, and the need to evaluate intervention effectiveness over time. This review provides perspectives to inform policymakers, urban planners, and researchers on how group-based interventions in nature can alleviate feelings of loneliness. By linking landscapes with public health concerns, municipalities can further promote and amplify the value of urban nature to the public.</p