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Social anxiety, cannabis use motives, and social context’s impact on willingness to use cannabis
No full textSocial anxiety is often purported to be a risk factor for increased cannabis use. Cannabis use motives are strong explanatory predictors of cannabis use embedded within social contexts. This investigation explored the impact of social anxiety, cannabis motives, and their interaction on willingness to use cannabis in a community sample of emerging adults. Social anxiety was anticipated to positively correlate with coping and conformity motives and greater willingness to use cannabis in peer social contexts. Motives to use were hypothesized to potentiate social anxiety’s influence on cannabis use decision-making. In total, 124 participants completed an audio simulation of social cannabis use contexts (Can-SIDE) and standard measures of social anxiety (SIAS) and use motives (MMM). Contrary to expectations, social anxiety exerted a protective effect on willingness to use cannabis, but only when conformity, social, and expansion motives were at or below average. These effects varied by social contexts of use. Social anxiety leading to increased cannabis use may be most apparent in clinical samples and in high-risk cannabis users, but this pattern was not supported in this sample of community living emerging adults below clinical cutoffs for cannabis use disorder with relatively high social anxiety
S-n curve characterisation for composite materials and prediction of remaining fatigue life using damage function
No full textS-N curve characterisation and prediction of remaining fatigue life are studied using polyethylene terephthalate glycol-modified (PETG). A new simple method for finding a data point at the lowest number of cycles for the Kim and Zhang S-N curve model is proposed to avoid the arbitrary choice of loading rate for tensile testing. It was demonstrated that the arbitrary choice of loading rate may likely lead to an erroneous characterisation for the prediction of the remaining fatigue life. The previously proposed theoretical method for predicting the remaining fatigue life of composite materials involving the damage function was verified at a stress ratio of 0.4 for the first time. Both high to low and low to high loadings were conducted for predicting the remaining fatigue lives and a good agreement between predictions and experimental results was found. Fatigue damage consisting of cracks and whitening is described
Provenance and structure of the Yancannia Formation, southern Thomson Orogen: implications for the tectono-stratigraphic evolution of the Cambro-Ordovician western Tasmanides
No full textThe upper Cambrian Yancannia Formation is a small and isolated basement exposure situated in the southern Thomson Orogen, northwestern New South Wales. Understanding the geology of the Yancannia Formation is important, as it offers a rare glimpse of the composition and structure of the mostly covered basement rocks of the southern Thomson Orogen. It consists of deformed fine-grained, lithic-rich, turbiditic metasediments, suggesting deposition in a proximal, low-energy deep-marine environment. A 497 ± 13 Ma U-Pb detrital zircon date provides its maximum depositional age, the same as previously published for a tuff horizon in a correlative unit. Analysis of sedimentological, geochronological and geophysical data confirms the Yancannia Formation belongs to the Warratta Group. The Warratta Group exhibits many similarities to the Teltawongee Group in the adjacent Delamerian Orogen, including similar provenance, sedimentology and deep-water turbiditic depositional environment. Additionally, there is no sedimentological evidence for deposition of the Warratta Group following the ca 500 Ma Delamerian Orogeny, which suggests that the Warratta Group is syn-Delamerian. However, no geochronological or structural evidence for Delamerian orogenesis was observed in the Warratta Group, suggesting that the group was either unaffected by Delamerian orogenesis, or that no conclusive record remains. The provenance signature of the Warratta Group also bears strong similarities with the upper Cambrian Stawell Zone Saint Arnaud Group in the western Lachlan Orogen. Units east of Yancannia have similar provenance signatures to the Lower Ordovician Girilambone Group of the Lachlan Orogen, suggesting equivalents exist in the southern Thomson Orogen. These are likely to be the Thomson beds, deposited in a deep-marine setting outboard of the Delamerian continental margin. Structural analysis from a ~10km, semi-continuous, across-strike section indicates a major, kilometre-scale, upright, shallow northwest-trending, doubly plunging anticline dominates the Yancannia region. This D1 structure was associated with tight-to-isoclinal folding, penetrative cleavage and abundant quartz veining of probable Benambran age. Later dextral transpressional deformation (D2) produced a sporadic, weak cleavage and dextral faulting, possibly of Bindian age. Major south-directed thrusting (D3) on the adjacent Olepoloko Fault occurred in the early Carboniferous and appears to pre-date a later deformation event (D4), which was associated with kink folding
Tourismscapes and destination sustainability: a case study of Da Nang and Hue, Vietnam
No full textTourism can be a driver for the implementation of the UN Sustainable Development Goals (SDGs). In order to align tourism with the SDGs, there is a need for collaboration strategies and governance structures that involve multiple actors across various sectors. Stakeholder collaboration is at the heart of SDG17, a goal that focuses on inclusive partnerships for sustainable development. This research examines the ways by which stakeholders interact and work together in partnerships towards sustainability in two provincial destinations in Vietnam. Specifically, this thesis addresses the question: how do multiple stakeholders work collectively towards sustainability at tourism destinations? This thesis presents a framework that integrates actor-network theory (ANT) and social network analysis (SNA) to conceptualise the multiplicities of entities and relationships within destination tourismscapes. This study adopts a multiple-case study strategy focusing on Da Nang City and Hue Province in Vietnam. An initial document analysis highlights that these destinations are exemplars of cities experiencing issues relating to sustainable tourism development. This study focuses on stakeholder actions and interactions in tourism development at the Son Tra peninsula in Da Nang city and the Complex of Hue Monuments in Hue Province to analyse sustainability issues. The research design engages various methods to gain critical insight into stakeholder networks, relationships, and actions. First, a social network analysis identified cooperation between stakeholders to assist in explaining networks for sustainability and the dynamics of stakeholder relationships. Second, document analysis, in-depth interviews, and onsite observations of activities and interactions of individuals and organisations were carried out during a period of fieldwork from June to October 2018. The findings of the Da Nang case study reveal how entities of the destination were involved in collective actions to challenge tourism development and protect the natural environment at Son Tra Peninsula. This involvement informed the formation of a self-regulating action network and influenced the dynamics of stakeholder relationships in Da Nang. The findings of the Hue case study reveal how entities of the destination assembled into three networks working to rejuvenate tourism at the same time as preserving cultural heritage. These actor networks in Hue informed a strategic vision for sustainable heritage tourism and influenced the dynamics of stakeholder relationships. These case study findings evidence a shift within each destination from an initial focus on tourism development (Da Nang) or cultural heritage preservation (Hue) to a focus on community involvement and a balance between preservation and development. These findings are presented as tourismscapes through a cross-case analysis that synthesises the networks and the networking processes. Governance for sustainability is understood as involving hybrid relationships of cooperation and competition/conflict (‘coopetition’), which are established as essential for sustainable tourism. The material model of tourismscapes offers a visualised representation of the dynamics of tourism destinations in the development process. This model offers a deeper insight into the multiplicities of actors in the pursuit of destination sustainability. Thus, tourismscapes for destination sustainability sheds new light on the dynamics of stakeholder collaborations and partnerships to promote inclusiveness and balance between human and non-human actors. Recognition and engagement with the multiplicities of actors, networks and destinations are found to be essential for the pursuit of SDG17 at tourism destinations
Dechlorination and defluorination capability of sulfidized nanoscale zerovalent iron with suppressed water reactivity
No full textRecently, sulfidation of nanoscale zerovalent iron (S-nZVI) has become a potential remediation technology. However, the impact of sulfidation methods and actual sulfur content ([S/Fe]particle) on the physicochemical properties and the reactivity of S-nZVI remains unknown. Here, we synthesized S-nZVI via one co-sulfidation and three post-sulfidation methods to determine how different sulfur reagents and addition procedures affect the reactivity of S-nZVI for defluorination. The measured S amounts of co-sulfidized S-nZVI and post-sulfidized S-nZVI was much lower than their dose. Different sulfur reagents and sulfidation approach would affect the amount and speciation of sulfur in the particles. Sulfidation of nZVI improved the reactivity for dechlorination (up to 12-fold) and defluorination (up to 3-fold) of florfenicol (FF), but inhibited the reactivity with water (up to 31-fold). Density functional theory calculations showed that sulfidation increases the hydrophobicity of materials, and the amount and nature of sulfur affect the hydrophobicity and the number of blocked H sites. S-nZVI particles with more S2- and S22- species showed faster dechlorination and defluorination of FF. Up to ~ 45% of FF was defluorinated by S-nZVI after 15 days reaction at room temperature and pressure. The [S/Fe]particle and Fe0 content was responsible for the initial and long-term defluorination, respectively. These results suggest that S-nZVI could be a promising agent for defluorination, and the sulfur reagents and sulfidation approach would affect its properties and reactivity
Cost-effectiveness of an intervention to improve the quality of nursing care among immobile patients with stroke in China: a multicenter study
No full textBackground: While a nursing intervention program for immobile patients with stroke can improve clinic outcomes, less is known about the cost-effectiveness of these interventions. Objectives: The goal of this study was to evaluate the cost-effectiveness of the intervention program for immobile patients with stroke in China. Design: A cost-effectiveness analysis alongside a pre-test/post-test (before and after) study was undertaken from a health care perspective. Settings: Participants were recruited from 25 hospitals among six provinces or municipal cities in eastern (Guangdong province, Zhejiang province, and Beijing municipal city), western (Sichuan province), and central (Henan province and Hubei province) China. Participants: A total of 7,653 immobile stroke patients were included in our sample. Patients in routine care settings were recruited from November 2015 to June 2016, and the recruitment of the intervention group patients was from November 2016 to July 2017. Methods: To adjust for potential bias from confounding variables, the 1:1 propensity score matching yielded matched pairs of 2,966 patients in the routine care group and 2,966 patients in the intervention group, with no significant differences in sociodemographic or clinical characteristics between two groups. All patients were followed-up 3 months after enrolment in the study. Total healthcare costs were extracted from the hospital information system, with the health outcome effectiveness of the intervention program measured using the EuroQol five-dimensional questionnaire (EQ-5D) instrument and the cost-effectiveness of the intervention measured by the incremental cost-effectiveness ratio with a time horizon of 3 months. Results: Compared to routine care, the intervention program decreased the total costs of stroke patients by CN¥4,600 (95% confidence interval [CI]: [-7050, -2151]), while increasing quality-adjusted life year 0.009 (95% CI: [0.005, 0.013]). The incremental cost-effectiveness ratios over 3 months was CN¥–517,011 per quality-adjusted life year (95% CI: [-1,111,442, -203,912]). Subgroup analysis reveals that both the health-related quality of life and cost effectiveness improved significantly for ischemic patients and tertiary hospitals patients while for hemorrhagic patients and non-tertiary hospital patients only the health-related quality of life improved significantly. Conclusions: Findings from this first cost-effectiveness analysis in immobile stroke patients provide evidence that an intervention program provided significant cost saving, but mainly in ischemic patients and tertiary hospital patients. Wider adoption of such programs may be a sensible approach to reducing the burden of stroke and for immobile patients more generally
A qualitative investigation into Chinese doctoral students’ cross-cultural adaptation in Australian universities
No full textDue to the globalisation of higher education, the number of Chinese students who are preparing for and eager to study abroad has been increasing. There remains, however, a dearth of research into the experience of Chinese doctoral students abroad, as most studies either concentrate on coursework students or treat Chinese students as part of a homogeneous group under the umbrella term of international students. Grounded in Australia, one of the top three leading destinations for Chinese students, this study seeks to understand how Chinese doctoral students perceive their lived experience of adapting to the academic and research environment in Australian universities. This study constellates an innovative data collection, constituting techniques of interview, critical incident, and visual graphic. Heeding to a self-formation paradigm that challenges a misinterpreted and pathologised stereotype, this study probes into Chinese doctoral students’ emic perception of their cross-cultural adaptation from a human development perspective. Investigation develops around three phrases, focusing respectively on how motivated and prepared they were for the overseas study (planning phase investigation), how they experience their adaptation as active agents (implementing phase investigation), and how they evaluate their overseas doctoral journey (reflecting phase investigation). The thesis makes theoretical, empirical and methodological contribution to the study of overseas doctoral students’ cross-cultural adaptation. Organising its analysis through a synergistic framework of three-phrase cultural adaptation, it articulates and synthesises research ideas pertaining to adaptation within a spatial-temporal continuum that conflates pertinent theories into a new analytic lens. Empirically, findings from the research contribute to various stakeholders in terms of bolstering the effectiveness of cross-cultural adaptation and that of the internationalisation of doctoral education. Methodologically, a combination of popular techniques and underused instruments such as graphics and maps draws on merits of each technique to disclose a full picture of the issue concerned in an in-depth manner. The thesis will be most valuable to researchers in cultural studies and practitioners in international education, or in a broader sense anyone who has a keen interest in knowing how individuals navigate a learning trajectory and construe meanings in unfamiliar academic and socio-cultural settings, not least Chinese PhDs studying in Western countries
Bilinguals' and monolinguals' performance on a non-verbal cognitive control task: how bilingual language experience contributes to cognitive performance by reducing mixing and switching costs
No full textAims and objectives/purpose/research questions: The study investigated whether language experience predicts cognitive performance in bilingual and monolingual adults. As indicators of language experience, we focused on language context, typological proximity/distance between two languages and onset age of active bilingualism. As indicators of cognitive performance, we measured mixing costs and switching costs to gauge proactive and reactive control processes during a computerized non-verbal cognitive control task. Design/methodology/approach: Demographic and language data were collected with the Language and Social Background Questionnaire. Mixing and switching costs were subsequently obtained using a cued non-verbal switching task. Data and analysis: The background and switching-task data obtained from 60 bilinguals from non-English-speaking backgrounds and 24 English monolinguals residing in Australia were analysed using linear fixed-effects regression analyses. Findings/conclusions: The results showed that the use of two languages in a dual-language context was associated with reduced switching costs relative to monolingual and bilingual separated-language contexts and with reduced mixing costs only relative to a bilingual separated-language context. Among the bilinguals, lower mixing costs were also associated with an earlier onset age of active bilingualism and smaller typological distance between two languages. Originality: This study’s design included bilinguals as a target group and monolinguals as a control group, thus enabling the identification of possible mixing and/or switching cost advantages in bilinguals. By targeting young/middle-aged adults and considering a set of potentially relevant language experiences, this work was, therefore, well placed to provide clarity on findings for an age group that previously returned mixed and inconclusive results regarding a bilingual advantage. Significance/implications: Our findings reinforce the idea that particular dimensions of bilingual experience rather than bilingualism per se are linked to enhanced cognitive performance
A mechanistic study of the structural transformations in Australian coking coals and blends across the plastic layer during coking
No full textThe quality of coke is virtually determined by the chemistry in the plastic layers that form during the coking process. Much of the previous research in the open literature on the underlying chemistry of the thermoplastic behaviours of single coals and blends have been carried out under impractical coking conditions, in terms of the sample sizes, the dimensions of the coal beds and the heating conditions in particular. When a single coal or coal blend is heated inside a coking oven, they undergo complex chemical and physical changes during the pyrolysis process. A plastic layer is formed during the coking process when the temperature of the coal bed is increased to 350 °C. The plastic layer is a foam-like thermoplastic material which consists of molten vitrinite and liptinite and solid coal components (inertinite macerals). However, volatile matters are generated by the decomposition of the coal during the coking process. The plastic layers initially form near the oven walls and migrate towards the centre of the oven. The formation of the cross-linking structures in the thermoplastic range is crucially associated with the quality of the coke produced. Due to the limited resources of premium coking coals in the world, coal blending has become a common practice in the coke making industries. The quality of a coke product is influenced by the interactions between individual coals in the blends during the coking process. Therefore, an understanding of the changes in the chemical and physical structures that take place during the formation of the plastic layers of coking coals and their blends is a core part of what determines a coke oven’s operations and the quality of the cokes that it produces. Therefore, one of the main objectives of this study is to investigate the changes in the physicochemical structures of the selected Australian coking coals and their blends during the formation of their plastic layers. This research is primarily focused on: (a) studying the behaviours of the Australian coking coals and their blends during the coking process in a 4 kg laboratory-scale coke oven, i.e., the changes in the thicknesses of the plastic layers and the transformations in the internal gas pressures; (b) characterising the changes in the physical structures, i.e., the transformations in the macropores and the coalescence of the macropores in the thermoplastic range during the coking of the coal blends; (c) representing the changes in the chemical structures of coal blends during the formation of their plastic layers, e.g., bridge bonds, looped structures, side chains, protonated aromatic carbons, carbon boned aromatic carbons and the sizes of the aromatic clusters; (d) elucidating the correlations between the physical structures and the chemical structures in the plastic layers during heating. To achieve these objectives, a 4 kg laboratory-scale dual-wall heated coke oven testing rig at the Newcastle Institute for Energy and Resources (NIER) site at the University of Newcastle was employed for the in-situ measurements (temperature histories and internal gas pressures in different locations in the coal charges) and the plastic layer sampling. Three Australian coking coals with similar ranks but with different vitrinite contents and Gieseler fluidities were blended with different blending compositions. The plastic layer samples were analysed using several quantitative analytical techniques, including Synchrotron micro-CT (SMCT), 3D image analysis software (GeoDict), Synchrotron infrared spectrometer (Synchrotron IR), solid-state 13carbon nuclear magnetic resonance (13C NMR) spectroscopy and micro gas chromatography (micro-GC), in order to understand the transformations in the physicochemical structures of the Australian coking coals and their blends. The results from the in-situ measurements during the coking process, i.e., the changes in the thicknesses of the plastic layers and the internal gas pressures, has shown that: (a) the addition of a coking coal with a high vitrinite content and high Gieseler fluidity to the coal blends seemed to significantly influence the thicknesses of the plastic layers; (b) the addition of a coking coal with a high vitrinite content and high Gieseler fluidity to the coal blends appeared to improve the maximum internal gas pressure (IGP) in the centre of the coke oven. These results essentially meant that the impacts of the characteristics of the coal blends are critical in determining their coking behaviours in a coke oven. A comprehensive study of the transformations in the physicochemical structures of coals and blends in their plastic layers is valuable in order to determine a coke oven’s operations and the quality of the coke it can produce. Firstly, the transformations in the physical structures of the Australian coking coals and their blends in the thermoplastic range were analysed using various 3D structural parameters, such as the total void fraction, the numbers of total and isolated voids, and the pore size distributions. Based on the analysis of the 3D images, the coalescence of the pores in the thermoplastic region during the coking process has been clarified. It was also clearly shown that the blending of high vitrinite coals in blends creates more large pores and closed pores during the plastic layer stage. This increased the chances of producing coalesced pore structures and more significant total porosities. With an increase in the proportion of the high vitrinite coking coal in the blend, more channel-like pore structures and large-sized pores were formed during the plastic layers. The analysis of the 3D images also enabled the characterisation of the pore connectivity that was not possible using 2D image analysis. The changes in the chemical structures during the formation of the plastic layer are then elucidated through a combination of Synchrotron IR, 13C NMR spectroscopy and micro-GC. It was evident that there are dramatic changes in the chemical structures during the plastic layer stage due to the cross-linking reactions, side chain elimination and release of volatile matters. Both the 13C NMR and Synchrotron IR analyses showed that the total aromaticity increased consistently in the plastic layers for all of the coals tested, while the amounts of the side chains decreased significantly in the plastic layer. There was a clear trend showing that the total number of bridge bonds and looped structures increased, indicating that the degree of cross-linking would increase throughout the plastic layer after certain stages of the coking process. It was found that the changes in the cross-linking structures in the plastic layers were strongly dependent on the properties of the parent coking coals. It appears that the plastic layer samples from the coals with low fluidities exhibited cross-linking structures with a high degree of branching and aromaticity, while the coals with high fluidities formed cross-linking structures with a relatively low degree of aromaticity and branching, but with a large number of bridge bonds and looped structures. The analysis of the gases using micro-GC verified the cross-linking reactions and side chain elimination that had been reflected in the Synchrotron IR and 13C NMR results. It is likely that the transferable methyl carbons, methylene carbons and hydrogen were strongly correlated to the cross-linking reactions and side chain elimination in the thermoplastic region, which was reflected in the release profiles of the methane and hydrogen gases during the plastic layer stage. It was also found that the addition of coals with a high vitrinite content and high Gieseler fluidity in a blend with a coal with a low vitrinite content and low Gieseler fluidity seemed to significantly impact on the nature of the parent coal. Finally, in ordering to correlate the physical structures with the chemical structures in the plastic layer stage, the parameters of the macropore structures, i.e., the macroporosity and number of macropores, were analysed as a function of the parameters of the chemical structures in the plastic layer, i.e., the average number of methyl carbons per cluster, the average number of methylene carbons per cluster, and the average number of total aromatic carbons per cluster. It was noted that there was an overall increase in the macroporosity, which was accompanied by dramatic changes in the chemical structures during the formation of the plastic layer, i.e., a strong increase in the methylene carbons, a decrease in the methyl carbons and a decrease in the total aromatic carbons. The decrease in the number of macropores was also accompanied by a decrease in the aromatic structures during the formation of the plastic layer. However, the changes in the number of macropores are not strongly correlated with the transformations in the methylene carbons, methyl carbons and the degree of aromaticity in the thermoplastic range, suggesting that the transformations in the macropores are dramatically impacted by the changes in the cross-linking structures and the release of the volatile matters, i.e., methane and tar, during the formation of the plastic layer
Consumer-guided development of an engagement-facilitation intervention for increasing uptake and adherence for self-guided web-based mental health programs: focus groups and online evaluation survey
No full textBACKGROUND:Self-guided web-based mental health programs are effective in treating and preventing mental health problems. However, current engagement with these programs in the community is suboptimal, and there is limited evidence indicating how to increase the use of existing evidence-based programs. OBJECTIVE:This study aims to investigate the views of people with lived experience of depression and anxiety on factors influencing their engagement with self-guided web-based mental health (e-mental health) programs and to use these perspectives to develop an engagement-facilitation intervention (EFI) to increase engagement (defined as both uptake and adherence) with these programs. METHODS:A total of 24 community members (female=21; male=3) with lived experience of depression and anxiety or depression or anxiety alone participated in 1 of 4 focus groups discussing the factors influencing their engagement with self-guided e-mental health programs and the appearance, delivery mode, and functionality of content for the proposed EFI. A subsequent evaluation survey of the focus group participants (n=14) was conducted to evaluate the resultant draft EFI. Data were thematically analyzed using both inductive and deductive qualitative methods. RESULTS:Participants suggested that the critical component of an EFI was information that would challenge personal barriers to engagement, including receiving personalized symptom feedback, information regarding the program's content or effectiveness and data security, and normalization of using e-mental health programs (eg, testimonials). Reminders, rewards, feedback about progress, and coaching were all mentioned as facilitating adherence. CONCLUSIONS:EFIs have the potential to improve community uptake of e-mental health programs. They should focus on providing information on the content and effectiveness of e-mental health programs and normalizing their use. Given that the sample comprised predominantly young females, this study may not be generalizable to other population groups. There is a strong value in involving people with a lived experience in the design and development of EFIs to maximize their effectiveness