Does an aging population influence stock markets? Evidence from New Zealand
- Hettihewa, Samanthala, Saha, Shrabani, Zhang, Hanxiong
- Authors: Hettihewa, Samanthala , Saha, Shrabani , Zhang, Hanxiong
- Date: 2018
- Type: Text , Journal article
- Relation: Economic Modelling Vol. 75, no. (2018), p. 142-158
- Full Text:
- Reviewed:
- Description: The effect of the aging baby-boom-cohort on asset values is extensively studied. While that effect varies by country, there are likely to be commonalities. Thus, research on a relatively small advanced open economy like New Zealand can provide insight into the general effect. In this study monthly data from 1991 to 2017 is used to examine how aging population in New Zealand affects its stock market considering key demographic and non-demographic macroeconomic variables and a new focus on fast-and-slow-moving institutional change. The results suggest that the net effect of an aging population on stock markets is insignificant. However, real GDP and foreign portfolio investment (FPI) show a positive relationship with the stock market. The findings reveal that FPI can mitigate possible negative effects from aging in an open economy. Moreover, the policy implications of the study suggest that international-factor mobility, skilled-migration policies, and technology-based productivity growth can boost stock markets.
- Authors: Hettihewa, Samanthala , Saha, Shrabani , Zhang, Hanxiong
- Date: 2018
- Type: Text , Journal article
- Relation: Economic Modelling Vol. 75, no. (2018), p. 142-158
- Full Text:
- Reviewed:
- Description: The effect of the aging baby-boom-cohort on asset values is extensively studied. While that effect varies by country, there are likely to be commonalities. Thus, research on a relatively small advanced open economy like New Zealand can provide insight into the general effect. In this study monthly data from 1991 to 2017 is used to examine how aging population in New Zealand affects its stock market considering key demographic and non-demographic macroeconomic variables and a new focus on fast-and-slow-moving institutional change. The results suggest that the net effect of an aging population on stock markets is insignificant. However, real GDP and foreign portfolio investment (FPI) show a positive relationship with the stock market. The findings reveal that FPI can mitigate possible negative effects from aging in an open economy. Moreover, the policy implications of the study suggest that international-factor mobility, skilled-migration policies, and technology-based productivity growth can boost stock markets.
Double bundle method for finding clarke stationary points in nonsmooth dc programming
- Joki, Kaisa, Bagirov, Adil, Karmitsa, Napsu, Makela, Marko, Taheri, Sona
- Authors: Joki, Kaisa , Bagirov, Adil , Karmitsa, Napsu , Makela, Marko , Taheri, Sona
- Date: 2018
- Type: Text , Journal article
- Relation: SIAM Journal on Optimization Vol. 28, no. 2 (2018), p. 1892-1919
- Relation: http://purl.org/au-research/grants/arc/DP140103213
- Full Text:
- Reviewed:
- Description: The aim of this paper is to introduce a new proximal double bundle method for unconstrained nonsmooth optimization, where the objective function is presented as a difference of two convex (DC) functions. The novelty in our method is a new escape procedure which enables us to guarantee approximate Clarke stationarity for solutions by utilizing the DC components of the objective function. This optimality condition is stronger than the criticality condition typically used in DC programming. Moreover, if a candidate solution is not approximate Clarke stationary, then the escape procedure returns a descent direction. With this escape procedure, we can avoid some shortcomings encountered when criticality is used. The finite termination of the double bundle method to an approximate Clarke stationary point is proved by assuming that the subdifferentials of DC components are polytopes. Finally, some encouraging numerical results are presented.
- Authors: Joki, Kaisa , Bagirov, Adil , Karmitsa, Napsu , Makela, Marko , Taheri, Sona
- Date: 2018
- Type: Text , Journal article
- Relation: SIAM Journal on Optimization Vol. 28, no. 2 (2018), p. 1892-1919
- Relation: http://purl.org/au-research/grants/arc/DP140103213
- Full Text:
- Reviewed:
- Description: The aim of this paper is to introduce a new proximal double bundle method for unconstrained nonsmooth optimization, where the objective function is presented as a difference of two convex (DC) functions. The novelty in our method is a new escape procedure which enables us to guarantee approximate Clarke stationarity for solutions by utilizing the DC components of the objective function. This optimality condition is stronger than the criticality condition typically used in DC programming. Moreover, if a candidate solution is not approximate Clarke stationary, then the escape procedure returns a descent direction. With this escape procedure, we can avoid some shortcomings encountered when criticality is used. The finite termination of the double bundle method to an approximate Clarke stationary point is proved by assuming that the subdifferentials of DC components are polytopes. Finally, some encouraging numerical results are presented.
Down the rabbit hole : Assessing the influence of schizotypy on the experience of the Barbie Doll Illusion
- Van Doorn, George, De Foe, Alexander, Wood, Alle, Wagstaff, Danielle, Hohwy, Jakob
- Authors: Van Doorn, George , De Foe, Alexander , Wood, Alle , Wagstaff, Danielle , Hohwy, Jakob
- Date: 2018
- Type: Text , Journal article
- Relation: Cognitive Neuropsychiatry Vol. 23, no. 5 (2018), p. 284-298
- Full Text:
- Reviewed:
- Description: Introduction: “Body swapping” illusions have been used to explore factors contributing to the experience of “owning” an artificial body. Preliminary research indicated that those people diagnosed with schizophrenia experience more vivid illusions of this kind than do “normal” individuals. Objectives: Here, we explored whether participants who rated themselves “high” on the cognitive-perceptual factor of the Schizotypal Personality Questionnaire (SPQ) experienced a more compelling sense of immersion in a variation of the body swapping illusion: The Barbie Doll Illusion. We also hypothesised that these individuals would experience a change in size perception when immersed in the illusion. Method: Forty-four participants wore a pair of Head-Mounted Display goggles connected to a video-camera, and thus a doll’s body replaced their own body in their visual field. In two conditions, touch was either applied synchronously or asynchronously to the doll’s and each participant’s leg. After each condition, participants filled out a questionnaire relating to their experience in the illusion. When both conditions were completed, they filled out the SPQ. Results: Our first hypothesis was confirmed, which suggested that people with higher cognitive-perceptual SPQ scores do indeed experience a more compelling Barbie Doll Illusion; however, our second hypothesis was not supported. Conclusion: Our study demonstrated, for the first time, that proneness to the positive and interpersonal factors of schizotypy in a normal population is sufficient to produce a compelling sense of swapping bodies.
- Authors: Van Doorn, George , De Foe, Alexander , Wood, Alle , Wagstaff, Danielle , Hohwy, Jakob
- Date: 2018
- Type: Text , Journal article
- Relation: Cognitive Neuropsychiatry Vol. 23, no. 5 (2018), p. 284-298
- Full Text:
- Reviewed:
- Description: Introduction: “Body swapping” illusions have been used to explore factors contributing to the experience of “owning” an artificial body. Preliminary research indicated that those people diagnosed with schizophrenia experience more vivid illusions of this kind than do “normal” individuals. Objectives: Here, we explored whether participants who rated themselves “high” on the cognitive-perceptual factor of the Schizotypal Personality Questionnaire (SPQ) experienced a more compelling sense of immersion in a variation of the body swapping illusion: The Barbie Doll Illusion. We also hypothesised that these individuals would experience a change in size perception when immersed in the illusion. Method: Forty-four participants wore a pair of Head-Mounted Display goggles connected to a video-camera, and thus a doll’s body replaced their own body in their visual field. In two conditions, touch was either applied synchronously or asynchronously to the doll’s and each participant’s leg. After each condition, participants filled out a questionnaire relating to their experience in the illusion. When both conditions were completed, they filled out the SPQ. Results: Our first hypothesis was confirmed, which suggested that people with higher cognitive-perceptual SPQ scores do indeed experience a more compelling Barbie Doll Illusion; however, our second hypothesis was not supported. Conclusion: Our study demonstrated, for the first time, that proneness to the positive and interpersonal factors of schizotypy in a normal population is sufficient to produce a compelling sense of swapping bodies.
Dynamic effects of ground-layer plant communities on beetles in a fragmented farming landscape
- Ng, Katherina, McIntyre, Sue, Macfadyen, Sarina, Barton, Philip, Driscoll, Don, Lindenmayer, David
- Authors: Ng, Katherina , McIntyre, Sue , Macfadyen, Sarina , Barton, Philip , Driscoll, Don , Lindenmayer, David
- Date: 2018
- Type: Text , Journal article
- Relation: Biodiversity and Conservation Vol. 27, no. 9 (2018), p. 2131-2153
- Full Text:
- Reviewed:
- Description: Vegetation effects on arthropods are well recognized, but it is unclear how different vegetation attributes might influence arthropod assemblages across mixed-agricultural landscapes. Understanding how plant communities influence arthropods under different habitat and seasonal contexts can identify vegetation management options for arthropod biodiversity. We examined relationships between vegetation structure, plant species richness and plant species composition, and the diversity and composition of beetles in different habitats and time periods. We asked: (1) What is the relative importance of plant species richness, vegetation structure and plant composition in explaining beetle species richness, activity-density and composition? (2) How do plant-beetle relationships vary between different habitats over time? We sampled beetles using pitfall traps and surveyed vegetation in three habitats (woodland, farmland, their edges) during peak crop growth in spring and post-harvest in summer. Plant composition better predicted beetle composition than vegetation structure. Both plant richness and vegetation structure significantly and positively affected beetle activity-density. The influence of all vegetation attributes often varied in strength and direction between habitats and seasons for all trophic groups. The variable nature of plant-beetle relationships suggests that vegetation management could be targeted at specific habitats and time periods to maximize positive outcomes for beetle diversity. In particular, management that promotes plant richness at edges, and promotes herbaceous cover during summer, can support beetle diversity. Conserving ground cover in all habitats may improve activity-density of all beetle trophic groups. The impacts of existing weed control strategies in Australian crop margins on arthropod biodiversity require further study. © 2018, Springer Science+Business Media B.V., part of Springer Nature.
- Authors: Ng, Katherina , McIntyre, Sue , Macfadyen, Sarina , Barton, Philip , Driscoll, Don , Lindenmayer, David
- Date: 2018
- Type: Text , Journal article
- Relation: Biodiversity and Conservation Vol. 27, no. 9 (2018), p. 2131-2153
- Full Text:
- Reviewed:
- Description: Vegetation effects on arthropods are well recognized, but it is unclear how different vegetation attributes might influence arthropod assemblages across mixed-agricultural landscapes. Understanding how plant communities influence arthropods under different habitat and seasonal contexts can identify vegetation management options for arthropod biodiversity. We examined relationships between vegetation structure, plant species richness and plant species composition, and the diversity and composition of beetles in different habitats and time periods. We asked: (1) What is the relative importance of plant species richness, vegetation structure and plant composition in explaining beetle species richness, activity-density and composition? (2) How do plant-beetle relationships vary between different habitats over time? We sampled beetles using pitfall traps and surveyed vegetation in three habitats (woodland, farmland, their edges) during peak crop growth in spring and post-harvest in summer. Plant composition better predicted beetle composition than vegetation structure. Both plant richness and vegetation structure significantly and positively affected beetle activity-density. The influence of all vegetation attributes often varied in strength and direction between habitats and seasons for all trophic groups. The variable nature of plant-beetle relationships suggests that vegetation management could be targeted at specific habitats and time periods to maximize positive outcomes for beetle diversity. In particular, management that promotes plant richness at edges, and promotes herbaceous cover during summer, can support beetle diversity. Conserving ground cover in all habitats may improve activity-density of all beetle trophic groups. The impacts of existing weed control strategies in Australian crop margins on arthropod biodiversity require further study. © 2018, Springer Science+Business Media B.V., part of Springer Nature.
Ecology of charophytes – permanent pioneers and ecosystem engineers
- Schubert, Hendrik, Blindow, Irmgard, Bueno, Norma, Casanova, Michelle, Pełechaty, Mariusz, Pukacz, Andrzej
- Authors: Schubert, Hendrik , Blindow, Irmgard , Bueno, Norma , Casanova, Michelle , Pełechaty, Mariusz , Pukacz, Andrzej
- Date: 2018
- Type: Text , Journal article
- Relation: Perspectives in Phycology Vol. 5, no. 1 (2018), p. 61-74
- Full Text:
- Reviewed:
- Description: For almost a century, charophytes have been regarded as a group that is confined to low-nutrient-clear water conditions. In light of recent research, this generalisation of the ecological niche dimensions of charophytes has changed and now includes more facets of ecological existence. In this review, the current knowledge with respect to species-specificity as well as temporal aspects – ontogenetic and successional ones – of the ecological requirements of charophytes are presented and discussed. This review identifies new directions for ecological research on charophytes as well as knowledge gaps to be filled, not just for reasons of academic curiosity, but also for applied purposes such as lake restoration, bioremediation and bioindication of water quality and water regime.
- Authors: Schubert, Hendrik , Blindow, Irmgard , Bueno, Norma , Casanova, Michelle , Pełechaty, Mariusz , Pukacz, Andrzej
- Date: 2018
- Type: Text , Journal article
- Relation: Perspectives in Phycology Vol. 5, no. 1 (2018), p. 61-74
- Full Text:
- Reviewed:
- Description: For almost a century, charophytes have been regarded as a group that is confined to low-nutrient-clear water conditions. In light of recent research, this generalisation of the ecological niche dimensions of charophytes has changed and now includes more facets of ecological existence. In this review, the current knowledge with respect to species-specificity as well as temporal aspects – ontogenetic and successional ones – of the ecological requirements of charophytes are presented and discussed. This review identifies new directions for ecological research on charophytes as well as knowledge gaps to be filled, not just for reasons of academic curiosity, but also for applied purposes such as lake restoration, bioremediation and bioindication of water quality and water regime.
Effect of a health coach intervention for the management of individuals with type 2 diabetes mellitus in China : a pragmatic cluster randomized controlled trial
- Chapman, Anna, Browning, Colette, Enticott, Joanne, Yang, Hui, Liu, Shuo, Zhang, Tuohong, Thomas, Shane
- Authors: Chapman, Anna , Browning, Colette , Enticott, Joanne , Yang, Hui , Liu, Shuo , Zhang, Tuohong , Thomas, Shane
- Date: 2018
- Type: Text , Journal article
- Relation: Frontiers in Public Health Vol. 6, (2018)
- Full Text:
- Reviewed:
- Description: Aim: To determine the effect of a health coach intervention for the management of glycemic control, as well as physiological, psychological and self-care outcomes of patients with type 2 diabetes mellitus (T2DM), compared with usual care. Methods:This pragmatic cluster RCT was conducted in the Fengtai district of Beijing from August 2011 to December 2013. Forty-one community health stations (CHSs) were cluster randomized (stratified geographically, 1:1 ratio) and eligible, randomly selected T2DM patients were sequentially contacted by CHSs. Control participants received usual care according to the Chinese Guideline for Diabetes Prevention and Management. Intervention participants received 18-months of health coaching based on principles of Motivational Interviewing (MI) plus usual care. Medical and pathology fees were waived for both groups. Outcome assessment was performed at baseline, 6, 12, and 18-months. The primary outcome was glycated hemoglobin (HbA1c); secondary outcomes encompassed a suite of physiological, psychological and self-care measures. Results:No differential treatment effect was found at 18-months for HbA1c (adj. difference -0.07, 95% CI -0.53 to 0.39, p = 0.769) or any specified secondary outcomes. Interestingly, both groups displayed a statistically and clinically significant within-group improvement of the same magnitude at 18-months for HbA1c (intervention: mean change -3.65, 95% CI -3.92 to -3.37; control: mean change -3.38, 95% CI -3.67 to -3.08). Conclusions:The lack of differential treatment effects observed indicate that it may be premature to recommend the routine delivery of health coach interventions based on MI principles for the management of T2DM in China. However, the large, comparable within-group improvement in mean HbA1c promotes the establishment of free, regular clinical health assessments for individuals with T2DM in China. © 2018 Chapman, Browning, Enticott, Yang, Liu, Zhang and Thomas.
- Authors: Chapman, Anna , Browning, Colette , Enticott, Joanne , Yang, Hui , Liu, Shuo , Zhang, Tuohong , Thomas, Shane
- Date: 2018
- Type: Text , Journal article
- Relation: Frontiers in Public Health Vol. 6, (2018)
- Full Text:
- Reviewed:
- Description: Aim: To determine the effect of a health coach intervention for the management of glycemic control, as well as physiological, psychological and self-care outcomes of patients with type 2 diabetes mellitus (T2DM), compared with usual care. Methods:This pragmatic cluster RCT was conducted in the Fengtai district of Beijing from August 2011 to December 2013. Forty-one community health stations (CHSs) were cluster randomized (stratified geographically, 1:1 ratio) and eligible, randomly selected T2DM patients were sequentially contacted by CHSs. Control participants received usual care according to the Chinese Guideline for Diabetes Prevention and Management. Intervention participants received 18-months of health coaching based on principles of Motivational Interviewing (MI) plus usual care. Medical and pathology fees were waived for both groups. Outcome assessment was performed at baseline, 6, 12, and 18-months. The primary outcome was glycated hemoglobin (HbA1c); secondary outcomes encompassed a suite of physiological, psychological and self-care measures. Results:No differential treatment effect was found at 18-months for HbA1c (adj. difference -0.07, 95% CI -0.53 to 0.39, p = 0.769) or any specified secondary outcomes. Interestingly, both groups displayed a statistically and clinically significant within-group improvement of the same magnitude at 18-months for HbA1c (intervention: mean change -3.65, 95% CI -3.92 to -3.37; control: mean change -3.38, 95% CI -3.67 to -3.08). Conclusions:The lack of differential treatment effects observed indicate that it may be premature to recommend the routine delivery of health coach interventions based on MI principles for the management of T2DM in China. However, the large, comparable within-group improvement in mean HbA1c promotes the establishment of free, regular clinical health assessments for individuals with T2DM in China. © 2018 Chapman, Browning, Enticott, Yang, Liu, Zhang and Thomas.
Effect of environmental factors on the germination and emergence of Salvia verbenaca L. cultivars (verbenaca and vernalis) : An invasive species in semi-arid and arid rangeland regions
- Javaid, Muhammad, Florentine, Singarayer, Ali, Hafiz, Weller, Sandra
- Authors: Javaid, Muhammad , Florentine, Singarayer , Ali, Hafiz , Weller, Sandra
- Date: 2018
- Type: Text , Journal article
- Relation: PLoS ONE Vol. 13, no. 3 (2018), p. 1-20
- Full Text:
- Reviewed:
- Description: Salvia verbenaca (wild sage) is a commonly cultivated herbal medicine plant, which is native to the Mediterranean climate regions of Europe, Africa, Asia and the Middle East. However, it has become an invasive species in semi-arid and arid regions of southern Australia. Two varieties are present in this region, var. verbenaca and var. vernalis, each of which can be distinguished by differences in morphology and flowering period. Following trials to determine the optimum temperate regime for germination and response to light and dark, seeds of both varieties were tested for their response to variations in pH, moisture stress, salinity, and burial depth. The temperature and light trial was carried out using three different temperature regimes; 30/20C, 25/15C and 20/12C, and two light regimes; 12 hours light/12 hours dark and 24 hours dark, with var. vernalis responding to relatively higher temperatures than var. verbenaca. The germination rate of neither species was significantly inhibited by complete darkness when compared to rates under periodic light exposure. Both varieties germinated at near optimum rates strongly to very strongly in all pH buffer solutions, from pH 5 to pH 10, but they responded most strongly at neutral pH. Var. vernalis showed slightly more tolerance to reduced moisture availability, moderate to strong salinity, and burial depth, compared to var. verbenaca. However, even a fairly shallow burial depth of 2 cm completely inhibited germination of both varieties. Thus, in circumstances where both varieties are present in a soil seedbank, var. vernalis could be expected to establish in more challenging conditions, where moisture is limited and salinity is ‘moderate to high’, implying that it is a more serious threat for invasive weed in conditions where crop plants are already challenged.
- Authors: Javaid, Muhammad , Florentine, Singarayer , Ali, Hafiz , Weller, Sandra
- Date: 2018
- Type: Text , Journal article
- Relation: PLoS ONE Vol. 13, no. 3 (2018), p. 1-20
- Full Text:
- Reviewed:
- Description: Salvia verbenaca (wild sage) is a commonly cultivated herbal medicine plant, which is native to the Mediterranean climate regions of Europe, Africa, Asia and the Middle East. However, it has become an invasive species in semi-arid and arid regions of southern Australia. Two varieties are present in this region, var. verbenaca and var. vernalis, each of which can be distinguished by differences in morphology and flowering period. Following trials to determine the optimum temperate regime for germination and response to light and dark, seeds of both varieties were tested for their response to variations in pH, moisture stress, salinity, and burial depth. The temperature and light trial was carried out using three different temperature regimes; 30/20C, 25/15C and 20/12C, and two light regimes; 12 hours light/12 hours dark and 24 hours dark, with var. vernalis responding to relatively higher temperatures than var. verbenaca. The germination rate of neither species was significantly inhibited by complete darkness when compared to rates under periodic light exposure. Both varieties germinated at near optimum rates strongly to very strongly in all pH buffer solutions, from pH 5 to pH 10, but they responded most strongly at neutral pH. Var. vernalis showed slightly more tolerance to reduced moisture availability, moderate to strong salinity, and burial depth, compared to var. verbenaca. However, even a fairly shallow burial depth of 2 cm completely inhibited germination of both varieties. Thus, in circumstances where both varieties are present in a soil seedbank, var. vernalis could be expected to establish in more challenging conditions, where moisture is limited and salinity is ‘moderate to high’, implying that it is a more serious threat for invasive weed in conditions where crop plants are already challenged.
Effective and efficient kernel-based image representations for classification and retrieval
- Authors: Karmakar, Priyabrata
- Date: 2018
- Type: Text , Thesis , PhD
- Full Text:
- Description: Image representation is a challenging task. In particular, in order to obtain better performances in different image processing applications such as video surveillance, autonomous driving, crime scene detection and automatic inspection, effective and efficient image representation is a fundamental need. The performance of these applications usually depends on how accurately images are classified into their corresponding groups or how precisely relevant images are retrieved from a database based on a query. Accuracy in image classification and precision in image retrieval depend on the effectiveness of image representation. Existing image representation methods have some limitations. For example, spatial pyramid matching, which is a popular method incorporating spatial information in image-level representation, has not been fully studied to date. In addition, the strengths of pyramid match kernel and spatial pyramid matching are not combined for better image matching. Kernel descriptors based on gradient, colour and shape overcome the limitations of histogram-based descriptors, but suffer from information loss, noise effects and high computational complexity. Furthermore, the combined performance of kernel descriptors has limitations related to computational complexity, higher dimensionality and lower effectiveness. Moreover, the potential of a global texture descriptor which is based on human visual perception has not been fully explored to date. Therefore, in this research project, kernel-based effective and efficient image representation methods are proposed to address the above limitations. An enhancement is made to spatial pyramid matching in terms of improved rotation invariance. This is done by investigating different partitioning schemes suitable to achieve rotation-invariant image representation and the proposal of a weight function for appropriate level contribution in image matching. In addition, the strengths of pyramid match kernel and spatial pyramid are combined to enhance matching accuracy between images. The existing kernel descriptors are modified and improved to achieve greater effectiveness, minimum noise effects, less dimensionality and lower computational complexity. A novel fusion approach is also proposed to combine the information related to all pixel attributes, before the descriptor extraction stage. Existing kernel descriptors are based only on gradient, colour and shape information. In this research project, a texture-based kernel descriptor is proposed by modifying an existing popular global texture descriptor. Finally, all the contributions are evaluated in an integrated system. The performances of the proposed methods are qualitatively and quantitatively evaluated on two to four different publicly available image databases. The experimental results show that the proposed methods are more effective and efficient in image representation than existing benchmark methods.
- Description: Doctor of Philosophy
- Authors: Karmakar, Priyabrata
- Date: 2018
- Type: Text , Thesis , PhD
- Full Text:
- Description: Image representation is a challenging task. In particular, in order to obtain better performances in different image processing applications such as video surveillance, autonomous driving, crime scene detection and automatic inspection, effective and efficient image representation is a fundamental need. The performance of these applications usually depends on how accurately images are classified into their corresponding groups or how precisely relevant images are retrieved from a database based on a query. Accuracy in image classification and precision in image retrieval depend on the effectiveness of image representation. Existing image representation methods have some limitations. For example, spatial pyramid matching, which is a popular method incorporating spatial information in image-level representation, has not been fully studied to date. In addition, the strengths of pyramid match kernel and spatial pyramid matching are not combined for better image matching. Kernel descriptors based on gradient, colour and shape overcome the limitations of histogram-based descriptors, but suffer from information loss, noise effects and high computational complexity. Furthermore, the combined performance of kernel descriptors has limitations related to computational complexity, higher dimensionality and lower effectiveness. Moreover, the potential of a global texture descriptor which is based on human visual perception has not been fully explored to date. Therefore, in this research project, kernel-based effective and efficient image representation methods are proposed to address the above limitations. An enhancement is made to spatial pyramid matching in terms of improved rotation invariance. This is done by investigating different partitioning schemes suitable to achieve rotation-invariant image representation and the proposal of a weight function for appropriate level contribution in image matching. In addition, the strengths of pyramid match kernel and spatial pyramid are combined to enhance matching accuracy between images. The existing kernel descriptors are modified and improved to achieve greater effectiveness, minimum noise effects, less dimensionality and lower computational complexity. A novel fusion approach is also proposed to combine the information related to all pixel attributes, before the descriptor extraction stage. Existing kernel descriptors are based only on gradient, colour and shape information. In this research project, a texture-based kernel descriptor is proposed by modifying an existing popular global texture descriptor. Finally, all the contributions are evaluated in an integrated system. The performances of the proposed methods are qualitatively and quantitatively evaluated on two to four different publicly available image databases. The experimental results show that the proposed methods are more effective and efficient in image representation than existing benchmark methods.
- Description: Doctor of Philosophy
Effectiveness of online tailored advice to prevent running-related injuries and promote preventive behaviour in Dutch trail runners : A pragmatic randomised controlled trial
- Hespanhol, Luiz, van Mechelen, Willem, Verhagen, Evert
- Authors: Hespanhol, Luiz , van Mechelen, Willem , Verhagen, Evert
- Date: 2018
- Type: Text , Journal article
- Relation: British journal of sports medicine Vol. 52, no. 13 (2018), p. 851-858
- Full Text:
- Reviewed:
- Description: BACKGROUND: Trail running is popular worldwide, but there is no preventive intervention for running-related injury (RRI). AIM: To evaluate the effectiveness of adding online tailored advice (TrailS6 ) to general advice on (1) the prevention of RRIs and (2) the determinants and actual preventive behaviour in Dutch trail runners. METHODS: Two-arm randomised controlled trial over 6 months. 232 trail runners were randomly assigned to an intervention or control group. All participants received online general advice on RRI prevention 1 week after baseline. Every 2 weeks, participants in the intervention group received specific advice tailored to their RRI status. The control group received no further intervention. Bayesian mixed models were used to analyse the data. RESULTS: Trail runners in the intervention group sustained 13% fewer RRIs compared with those in the control group after 6 months of follow-up (absolute risk difference -13.1%, 95% Bayesian highest posterior credible interval (95% BCI) -23.3 to -3.1). A preventive benefit was observed in one out of eight trail runners who had received the online tailored advice for 6 months (number needed to treat 8, 95% BCI 3 to 22). No significant between-group difference was observed on the determinants and actual preventive behaviours. CONCLUSIONS: Online tailored advice prevented RRIs among Dutch trail runners. Therefore, online tailored advice may be used as a preventive component in multicomponent RRI prevention programmes. No effect was observed on determinants and actual preventive behaviours. TRIAL REGISTRATION NUMBER: The Netherlands National Trial Register (NTR5431).
- Authors: Hespanhol, Luiz , van Mechelen, Willem , Verhagen, Evert
- Date: 2018
- Type: Text , Journal article
- Relation: British journal of sports medicine Vol. 52, no. 13 (2018), p. 851-858
- Full Text:
- Reviewed:
- Description: BACKGROUND: Trail running is popular worldwide, but there is no preventive intervention for running-related injury (RRI). AIM: To evaluate the effectiveness of adding online tailored advice (TrailS6 ) to general advice on (1) the prevention of RRIs and (2) the determinants and actual preventive behaviour in Dutch trail runners. METHODS: Two-arm randomised controlled trial over 6 months. 232 trail runners were randomly assigned to an intervention or control group. All participants received online general advice on RRI prevention 1 week after baseline. Every 2 weeks, participants in the intervention group received specific advice tailored to their RRI status. The control group received no further intervention. Bayesian mixed models were used to analyse the data. RESULTS: Trail runners in the intervention group sustained 13% fewer RRIs compared with those in the control group after 6 months of follow-up (absolute risk difference -13.1%, 95% Bayesian highest posterior credible interval (95% BCI) -23.3 to -3.1). A preventive benefit was observed in one out of eight trail runners who had received the online tailored advice for 6 months (number needed to treat 8, 95% BCI 3 to 22). No significant between-group difference was observed on the determinants and actual preventive behaviours. CONCLUSIONS: Online tailored advice prevented RRIs among Dutch trail runners. Therefore, online tailored advice may be used as a preventive component in multicomponent RRI prevention programmes. No effect was observed on determinants and actual preventive behaviours. TRIAL REGISTRATION NUMBER: The Netherlands National Trial Register (NTR5431).
Effects of fire regime on plant species richness and composition differ among forest, woodland and heath vegetation
- Foster, Claire, Barton, Philip, MacGregor, Christopher, Catford, Jane, Blanchard, Wade, Lindenmayer, David
- Authors: Foster, Claire , Barton, Philip , MacGregor, Christopher , Catford, Jane , Blanchard, Wade , Lindenmayer, David
- Date: 2018
- Type: Text , Journal article
- Relation: Applied Vegetation Science Vol. 21, no. 1 (2018), p. 132-143
- Full Text:
- Reviewed:
- Description: Question: Do the effects of fire regimes on plant species richness and composition differ among floristically similar vegetation types?. Location: Booderee National Park, south-eastern Australia. Methods: We completed floristic surveys of 87 sites in Sydney Coastal dry sclerophyll vegetation, where fire history records have been maintained for over 55 years. We tested for associations between different aspects of the recent fire history and plant species richness and composition, and whether these relationships were consistent among structurally defined forest, woodland and heath vegetation types. Results: The relationship between fire regime variables and plant species richness and composition differed among vegetation types, despite the three vegetation types having similar species pools. Fire frequency was positively related to species richness in woodland, negatively related to species richness in heath, and unrelated to species richness in forest. These different relationships were explained by differences in the associations between fire history and species traits among vegetation types. The negative relationship between fire frequency and species richness in heath vegetation was underpinned by reduced occurrence of resprouting species at high fire frequency sites (more than four fires in 55 years). However, in forest and woodland vegetation, resprouting species were not negatively associated with fire frequency. Conclusions: We hypothesize that differing relationships among vegetation types were underpinned by differences in fire behaviour, and/or biotic and abiotic conditions, leading to differences in plant species mortality and post-fire recovery among vegetation types. Our findings suggest that even when there is a high proportion of shared species between vegetation types, fires can have very different effects on vegetation communities, depending on the structural vegetation type. Both research and management of fire regimes may therefore benefit from considering vegetation types as separate management units. © 2017 International Association for Vegetation Science
- Authors: Foster, Claire , Barton, Philip , MacGregor, Christopher , Catford, Jane , Blanchard, Wade , Lindenmayer, David
- Date: 2018
- Type: Text , Journal article
- Relation: Applied Vegetation Science Vol. 21, no. 1 (2018), p. 132-143
- Full Text:
- Reviewed:
- Description: Question: Do the effects of fire regimes on plant species richness and composition differ among floristically similar vegetation types?. Location: Booderee National Park, south-eastern Australia. Methods: We completed floristic surveys of 87 sites in Sydney Coastal dry sclerophyll vegetation, where fire history records have been maintained for over 55 years. We tested for associations between different aspects of the recent fire history and plant species richness and composition, and whether these relationships were consistent among structurally defined forest, woodland and heath vegetation types. Results: The relationship between fire regime variables and plant species richness and composition differed among vegetation types, despite the three vegetation types having similar species pools. Fire frequency was positively related to species richness in woodland, negatively related to species richness in heath, and unrelated to species richness in forest. These different relationships were explained by differences in the associations between fire history and species traits among vegetation types. The negative relationship between fire frequency and species richness in heath vegetation was underpinned by reduced occurrence of resprouting species at high fire frequency sites (more than four fires in 55 years). However, in forest and woodland vegetation, resprouting species were not negatively associated with fire frequency. Conclusions: We hypothesize that differing relationships among vegetation types were underpinned by differences in fire behaviour, and/or biotic and abiotic conditions, leading to differences in plant species mortality and post-fire recovery among vegetation types. Our findings suggest that even when there is a high proportion of shared species between vegetation types, fires can have very different effects on vegetation communities, depending on the structural vegetation type. Both research and management of fire regimes may therefore benefit from considering vegetation types as separate management units. © 2017 International Association for Vegetation Science
Efficient video coding using visual sensitive information for HEVC coding standard
- Podder, Pallab, Paul, Manoranjan, Murshed, Manzur
- Authors: Podder, Pallab , Paul, Manoranjan , Murshed, Manzur
- Date: 2018
- Type: Text , Journal article
- Relation: IEEE Access Vol. 6, no. (2018), p. 75695-75708
- Full Text:
- Reviewed:
- Description: The latest high efficiency video coding (HEVC) standard introduces a large number of inter-mode block partitioning modes. The HEVC reference test model (HM) uses partially exhaustive tree-structured mode selection, which still explores a large number of prediction unit (PU) modes for a coding unit (CU). This impacts on encoding time rise which deprives a number of electronic devices having limited processing resources to use various features of HEVC. By analyzing the homogeneity, residual, and different statistical correlation among modes, many researchers speed-up the encoding process through the number of PU mode reduction. However, these approaches could not demonstrate the similar rate-distortion (RD) performance with the HM due to their dependency on existing Lagrangian cost function (LCF) within the HEVC framework. In this paper, to avoid the complete dependency on LCF in the initial phase, we exploit visual sensitive foreground motion and spatial salient metric (FMSSM) in a block. To capture its motion and saliency features, we use the dynamic background and visual saliency modeling, respectively. According to the FMSSM values, a subset of PU modes is then explored for encoding the CU. This preprocessing phase is independent from the existing LCF. As the proposed coding technique further reduces the number of PU modes using two simple criteria (i.e., motion and saliency), it outperforms the HM in terms of encoding time reduction. As it also encodes the uncovered and static background areas using the dynamic background frame as a substituted reference frame, it does not sacrifice quality. Tested results reveal that the proposed method achieves 32% average encoding time reduction of the HM without any quality loss for a wide range of videos.
- Authors: Podder, Pallab , Paul, Manoranjan , Murshed, Manzur
- Date: 2018
- Type: Text , Journal article
- Relation: IEEE Access Vol. 6, no. (2018), p. 75695-75708
- Full Text:
- Reviewed:
- Description: The latest high efficiency video coding (HEVC) standard introduces a large number of inter-mode block partitioning modes. The HEVC reference test model (HM) uses partially exhaustive tree-structured mode selection, which still explores a large number of prediction unit (PU) modes for a coding unit (CU). This impacts on encoding time rise which deprives a number of electronic devices having limited processing resources to use various features of HEVC. By analyzing the homogeneity, residual, and different statistical correlation among modes, many researchers speed-up the encoding process through the number of PU mode reduction. However, these approaches could not demonstrate the similar rate-distortion (RD) performance with the HM due to their dependency on existing Lagrangian cost function (LCF) within the HEVC framework. In this paper, to avoid the complete dependency on LCF in the initial phase, we exploit visual sensitive foreground motion and spatial salient metric (FMSSM) in a block. To capture its motion and saliency features, we use the dynamic background and visual saliency modeling, respectively. According to the FMSSM values, a subset of PU modes is then explored for encoding the CU. This preprocessing phase is independent from the existing LCF. As the proposed coding technique further reduces the number of PU modes using two simple criteria (i.e., motion and saliency), it outperforms the HM in terms of encoding time reduction. As it also encodes the uncovered and static background areas using the dynamic background frame as a substituted reference frame, it does not sacrifice quality. Tested results reveal that the proposed method achieves 32% average encoding time reduction of the HM without any quality loss for a wide range of videos.
Ekeland's inverse function theorem in graded Fréchet spaces revisited for multifunctions
- Huynh, Van Ngai, Théra, Michel
- Authors: Huynh, Van Ngai , Théra, Michel
- Date: 2018
- Type: Text , Journal article
- Relation: Journal of Mathematical Analysis and Applications Vol. 457, no. 2 (2018), p. 1403-1421
- Relation: http://purl.org/au-research/grants/arc/DP160100854
- Full Text:
- Reviewed:
- Description: In this paper, we present some inverse function theorems and implicit function theorems for set-valued mappings between Fréchet spaces. The proof relies on Lebesgue's Dominated Convergence Theorem and on Ekeland's variational principle. An application to the existence of solutions of differential equations in Fréchet spaces with non-smooth data is given.
- Authors: Huynh, Van Ngai , Théra, Michel
- Date: 2018
- Type: Text , Journal article
- Relation: Journal of Mathematical Analysis and Applications Vol. 457, no. 2 (2018), p. 1403-1421
- Relation: http://purl.org/au-research/grants/arc/DP160100854
- Full Text:
- Reviewed:
- Description: In this paper, we present some inverse function theorems and implicit function theorems for set-valued mappings between Fréchet spaces. The proof relies on Lebesgue's Dominated Convergence Theorem and on Ekeland's variational principle. An application to the existence of solutions of differential equations in Fréchet spaces with non-smooth data is given.
Elucidating the impact of micro-scale heterogeneous bacterial distribution on biodegradation
- Schmidt, Susanne, Kreft, Jan-Ulrich, Mackay, Rae, Picioreanu, Cristian, Thullner, Martin
- Authors: Schmidt, Susanne , Kreft, Jan-Ulrich , Mackay, Rae , Picioreanu, Cristian , Thullner, Martin
- Date: 2018
- Type: Text , Journal article
- Relation: Advances in Water Resources Vol. 116, no. (2018), p. 67-76
- Full Text:
- Reviewed:
- Description: Groundwater microorganisms hardly ever cover the solid matrix uniformly–instead they form micro-scale colonies. To which extent such colony formation limits the bioavailability and biodegradation of a substrate is poorly understood. We used a high-resolution numerical model of a single pore channel inhabited by bacterial colonies to simulate the transport and biodegradation of organic substrates. These high-resolution 2D simulation results were compared to 1D simulations that were based on effective rate laws for bioavailability-limited biodegradation. We (i) quantified the observed bioavailability limitations and (ii) evaluated the applicability of previously established effective rate concepts if microorganisms are heterogeneously distributed. Effective bioavailability reductions of up to more than one order of magnitude were observed, showing that the micro-scale aggregation of bacterial cells into colonies can severely restrict the bioavailability of a substrate and reduce in situ degradation rates. Effective rate laws proved applicable for upscaling when using the introduced effective colony sizes.
- Authors: Schmidt, Susanne , Kreft, Jan-Ulrich , Mackay, Rae , Picioreanu, Cristian , Thullner, Martin
- Date: 2018
- Type: Text , Journal article
- Relation: Advances in Water Resources Vol. 116, no. (2018), p. 67-76
- Full Text:
- Reviewed:
- Description: Groundwater microorganisms hardly ever cover the solid matrix uniformly–instead they form micro-scale colonies. To which extent such colony formation limits the bioavailability and biodegradation of a substrate is poorly understood. We used a high-resolution numerical model of a single pore channel inhabited by bacterial colonies to simulate the transport and biodegradation of organic substrates. These high-resolution 2D simulation results were compared to 1D simulations that were based on effective rate laws for bioavailability-limited biodegradation. We (i) quantified the observed bioavailability limitations and (ii) evaluated the applicability of previously established effective rate concepts if microorganisms are heterogeneously distributed. Effective bioavailability reductions of up to more than one order of magnitude were observed, showing that the micro-scale aggregation of bacterial cells into colonies can severely restrict the bioavailability of a substrate and reduce in situ degradation rates. Effective rate laws proved applicable for upscaling when using the introduced effective colony sizes.
Enhanced colour image retrieval with cuboid segmentation
- Murshed, Manzur, Karmakar, Priyabrata, Teng, Shyh, Lu, Guojun
- Authors: Murshed, Manzur , Karmakar, Priyabrata , Teng, Shyh , Lu, Guojun
- Date: 2018
- Type: Text , Conference proceedings , Conference paper
- Relation: 2018 International Conference on Digital Image Computing: Techniques and Applications, DICTA 2018; Canberra, Australia; 10th-13th December 2018
- Full Text:
- Reviewed:
- Description: In this paper, we further investigate our recently proposed cuboid image segmentation algorithm for effective image retrieval. Instead of using all cuboids (i.e. segments), we have proposed two approaches to choose different subsets of cuboids appropriately. With the experimental results on eBay dataset, we have shown that our proposals outperform retrieval performance of the existing technique. In addition, we have investigated how many segments are required for the most effective image retrieval and provide a quick method to determine the suitable number of cuboids.
- Description: 2018 International Conference on Digital Image Computing: Techniques and Applications, DICTA 2018
- Authors: Murshed, Manzur , Karmakar, Priyabrata , Teng, Shyh , Lu, Guojun
- Date: 2018
- Type: Text , Conference proceedings , Conference paper
- Relation: 2018 International Conference on Digital Image Computing: Techniques and Applications, DICTA 2018; Canberra, Australia; 10th-13th December 2018
- Full Text:
- Reviewed:
- Description: In this paper, we further investigate our recently proposed cuboid image segmentation algorithm for effective image retrieval. Instead of using all cuboids (i.e. segments), we have proposed two approaches to choose different subsets of cuboids appropriately. With the experimental results on eBay dataset, we have shown that our proposals outperform retrieval performance of the existing technique. In addition, we have investigated how many segments are required for the most effective image retrieval and provide a quick method to determine the suitable number of cuboids.
- Description: 2018 International Conference on Digital Image Computing: Techniques and Applications, DICTA 2018
Environmental factors effecting the germination and seedling emergence of two populations of an aggressive agricultural weed; Nassella trichotoma
- Humphries, Talia, Chauhan, Bhagirath, Florentine, Singarayer
- Authors: Humphries, Talia , Chauhan, Bhagirath , Florentine, Singarayer
- Date: 2018
- Type: Text , Journal article
- Relation: PLoS ONE Vol. 13, no. 7 (2018), p. 1-25
- Full Text:
- Reviewed:
- Description: Nassella trichotoma (Nees) Hack. ex Arechav. (Serrated tussock) is an aggressive globally significant weed to agricultural and natural ecosystems. Herbicide resistant populations of this C3 perennial weed have emerged, increasing the need for effective wide-scale cultural control strategies. A thorough seed ecology study on two spatially distinct populations of N. trichotoma was conducted on this weed to identify differences in important environmental factors (drought, salinity, alternating temperature, photoperiod, burial depth, soil pH, artificial seed aging, and radiant heat) which influence seed dormancy. Seeds were collected from two spatially distinct populations; Gnarwarre (38 O 9’ 8.892’’ S, 144 O 7’ 38.784’’ E) and Ingliston (37O 40’ 4.44’’ S, 144 O 18’ 39.24’’ E) in December 2016 and February 2017, respectively. Twenty sterilized seeds were placed into Petri dishes lined with a single Whatman® No. 10 filter paper dampened with the relevant treatments solution and then incubated under the identified optimal alternating temperature and photoperiod regime of 25C/ 15C (light/dark, 12h/12h). For the burial depth treatment, 20 seeds were placed into plastic containers (10cm in diameter and 6cm in depth) and buried to the relevant depth in sterilized soil. All trials were monitored for 30 days and germination was indicated by 5mm exposure of the radicle and emergence was indicated by the exposure of the cotyledon. Each treatment had three replicates for each population, and each treatment was repeated to give a total of six replicates per treatment, per population. Nassella trichotoma was identified to be non-photoblastic, with germination (%) being similar under alternating light and dark and complete darkness conditions. With an increase of osmotic potential and salinity, a significant decline in germination was observed. There was no effect of pH on germination. Exposure to a radiant heat of 120C for 9 minutes resulted in the lowest germination in the Ingliston population (33%) and the Gnarwarre population (60%). In the burial depth treatment, the Ingliston population and the Gnarwarre population had highest emergence of 75% and 80%, respectively at a depth of 1cm. Variation between the two populations was observed for the burial depth treatments; Gnarwarre had greater emergence than Ingliston from the 4cm burial depth, while Ingliston had greater emergence at the soil surface than Gnarwarre. The Gnarwarre population had greater overall germination than Ingliston, which could be attributed to the greater seed mass (0.86mg compared to 0.76mg, respectively). This study identifies that spatial variations in N. trichotoma’s seed ecology are present between spatially distinct populations.
- Authors: Humphries, Talia , Chauhan, Bhagirath , Florentine, Singarayer
- Date: 2018
- Type: Text , Journal article
- Relation: PLoS ONE Vol. 13, no. 7 (2018), p. 1-25
- Full Text:
- Reviewed:
- Description: Nassella trichotoma (Nees) Hack. ex Arechav. (Serrated tussock) is an aggressive globally significant weed to agricultural and natural ecosystems. Herbicide resistant populations of this C3 perennial weed have emerged, increasing the need for effective wide-scale cultural control strategies. A thorough seed ecology study on two spatially distinct populations of N. trichotoma was conducted on this weed to identify differences in important environmental factors (drought, salinity, alternating temperature, photoperiod, burial depth, soil pH, artificial seed aging, and radiant heat) which influence seed dormancy. Seeds were collected from two spatially distinct populations; Gnarwarre (38 O 9’ 8.892’’ S, 144 O 7’ 38.784’’ E) and Ingliston (37O 40’ 4.44’’ S, 144 O 18’ 39.24’’ E) in December 2016 and February 2017, respectively. Twenty sterilized seeds were placed into Petri dishes lined with a single Whatman® No. 10 filter paper dampened with the relevant treatments solution and then incubated under the identified optimal alternating temperature and photoperiod regime of 25C/ 15C (light/dark, 12h/12h). For the burial depth treatment, 20 seeds were placed into plastic containers (10cm in diameter and 6cm in depth) and buried to the relevant depth in sterilized soil. All trials were monitored for 30 days and germination was indicated by 5mm exposure of the radicle and emergence was indicated by the exposure of the cotyledon. Each treatment had three replicates for each population, and each treatment was repeated to give a total of six replicates per treatment, per population. Nassella trichotoma was identified to be non-photoblastic, with germination (%) being similar under alternating light and dark and complete darkness conditions. With an increase of osmotic potential and salinity, a significant decline in germination was observed. There was no effect of pH on germination. Exposure to a radiant heat of 120C for 9 minutes resulted in the lowest germination in the Ingliston population (33%) and the Gnarwarre population (60%). In the burial depth treatment, the Ingliston population and the Gnarwarre population had highest emergence of 75% and 80%, respectively at a depth of 1cm. Variation between the two populations was observed for the burial depth treatments; Gnarwarre had greater emergence than Ingliston from the 4cm burial depth, while Ingliston had greater emergence at the soil surface than Gnarwarre. The Gnarwarre population had greater overall germination than Ingliston, which could be attributed to the greater seed mass (0.86mg compared to 0.76mg, respectively). This study identifies that spatial variations in N. trichotoma’s seed ecology are present between spatially distinct populations.
Epidemiology, injury and illness prevention in Olympic combat sports
- Authors: Bromley, Sally
- Date: 2018
- Type: Text , Thesis , PhD
- Full Text:
- Description: Background: Olympic combat sports are commonly considered dangerous, however injury rates for these sports are not well understood. Isolated studies in combat sports have investigated injury, however these are mainly during competition, and therefore are unlikely to include significant or persistent injury which prevents athletes competing and participating in data collection. This thesis was undertaken as a series of linked studies, to provide further detail into the types, mechanisms and aetiology of injuries in combat sports. Methods: Study 1 was a systematic review that utilised the PRISMA guidelines to investigate the current evidence. Study 2 was a repeated measures study to examine the reliability of training load measures. Study 3 employed a longitudinal study design to assess the feasibility of injury, illness and training load monitoring. Finally, Study 4 was a cross-sectional cohort study that gathered perspectives of combat sport coaches and managers before and after an injury and illness prevention workshop. Results: Study 1 found one high-quality epidemiological study with low risk of bias in Judo. Variation in injury and illness definitions prevented cross-sport comparisons, however the injury incidence was comparable to other sports. In Study 2, rating of perceived exertion (RPE) was shown to have good stability across sessions (ICC=0.84), and no significant differences were found between coach (observed) and athlete (experienced) RPE (ordered logistic regression coefficient = 0.47 [1.51–0.57 95%CI]). Study 3 found that athlete engagement with the monitoring system was low, with only 13% of athletes entering data across a 12-week period. Irrespective of low engagement, 62 injuries and illnesses were recorded. In Study 4, combat sport coaches and managers were found to be generally well informed of the risk and seriousness of injury and illness, however, illness risk perceptions changed after the workshop (p=0.048). Discussion and Conclusion: Currently, cross-sport comparisons are not possible due to varying data methodology and study quality. Based upon the results presented in this thesis, RPE can be used as a tool to quantify training load in the sport of judo. Longitudinal surveillance of training load, injury and illness in combat sport is not currently feasible within the Australian system, due to low uptake and engagement. However, the collection of data on a large number of injuries and illnesses indicates that athletes are experiencing multiple, repeated health problems. Coaches and managers are well informed about injury and illness risk and seriousness, indicating that injury and illness prevention education alone may not translate to a decrease in injury and illness incidence in combat sport.
- Description: Doctor of Philosophy
- Authors: Bromley, Sally
- Date: 2018
- Type: Text , Thesis , PhD
- Full Text:
- Description: Background: Olympic combat sports are commonly considered dangerous, however injury rates for these sports are not well understood. Isolated studies in combat sports have investigated injury, however these are mainly during competition, and therefore are unlikely to include significant or persistent injury which prevents athletes competing and participating in data collection. This thesis was undertaken as a series of linked studies, to provide further detail into the types, mechanisms and aetiology of injuries in combat sports. Methods: Study 1 was a systematic review that utilised the PRISMA guidelines to investigate the current evidence. Study 2 was a repeated measures study to examine the reliability of training load measures. Study 3 employed a longitudinal study design to assess the feasibility of injury, illness and training load monitoring. Finally, Study 4 was a cross-sectional cohort study that gathered perspectives of combat sport coaches and managers before and after an injury and illness prevention workshop. Results: Study 1 found one high-quality epidemiological study with low risk of bias in Judo. Variation in injury and illness definitions prevented cross-sport comparisons, however the injury incidence was comparable to other sports. In Study 2, rating of perceived exertion (RPE) was shown to have good stability across sessions (ICC=0.84), and no significant differences were found between coach (observed) and athlete (experienced) RPE (ordered logistic regression coefficient = 0.47 [1.51–0.57 95%CI]). Study 3 found that athlete engagement with the monitoring system was low, with only 13% of athletes entering data across a 12-week period. Irrespective of low engagement, 62 injuries and illnesses were recorded. In Study 4, combat sport coaches and managers were found to be generally well informed of the risk and seriousness of injury and illness, however, illness risk perceptions changed after the workshop (p=0.048). Discussion and Conclusion: Currently, cross-sport comparisons are not possible due to varying data methodology and study quality. Based upon the results presented in this thesis, RPE can be used as a tool to quantify training load in the sport of judo. Longitudinal surveillance of training load, injury and illness in combat sport is not currently feasible within the Australian system, due to low uptake and engagement. However, the collection of data on a large number of injuries and illnesses indicates that athletes are experiencing multiple, repeated health problems. Coaches and managers are well informed about injury and illness risk and seriousness, indicating that injury and illness prevention education alone may not translate to a decrease in injury and illness incidence in combat sport.
- Description: Doctor of Philosophy
Epigenetic modifications in essential hypertension
- Authors: Wise, Ingrid
- Date: 2018
- Type: Text , Thesis , PhD
- Full Text:
- Description: Background: Hypertension (HTN) is a complex, multifactorial, quantitative trait under polygenic control that affects more than one billion people globally. Despite advances in our understanding of the pathophysiology of HTN and the implementation of more effective treatment and prevention strategies, HTN remains one of the world’s great public health problems. The accepted inference from genome-wide association studies (GWAS) is that the genetic code lays the foundation for transcriptomic changes and in turn physiological change. On the other side of the coin, environmental factors (smoking, diet, chemical exposure) can in turn affect DNA itself in genes relevant to blood pressure (BP). Variation in epigenetic forms of modification may thus explain additional phenotypic variation in BP and provide new clues to the physiological processes influencing its regulation. DNA methylation is one of these epigenetic mechanisms responsible for changes to gene expression, activated by interaction with environmental triggers. DNA methylation is a reversible epigenetic modifier of specific dinucleotide sites called CpGs, which consists of a transfer of a methyl group derived from S-adenosyl-L-methionine to position five of a cytosine ring, forming 5mC. Pathophysiologically, the kidney is known as the key organ of BP regulation and one of the most important contributors to HTN. According to the hypothesis put forward by Guyton, over 40 years ago, the control of BP in the steady-state and longer-term is critically dependent on renal mechanisms. In fact, almost all monogenic forms of HTN are driven by rare mutations in genes involved in salt handling in the distal nephron. It is therefore crucial to understand kidney DNA methylation changes that may drive gene expression in kidney and lead to HTN. Hypothesis: The central hypothesis underpinning this PhD thesis is that alterations in kidney specific DNA methylation plays a fundamental role in modulating gene expression changes involved in the regulation of BP and pathophysiology of EH. Aims: This PhD thesis focuses on characterising the role of DNA methylation in the hypertensive kidney using array and RNA-sequencing methods. Three major aims are addressed: • Aim 1: To characterise blood and kidney global DNA methylation dynamics and its functional role in the hypertensive population (Chapter 3). • Aim 2: To determine the role of genome-wide, loci specific DNA methylation in the hypertensive human kidney (Chapter 4). • Aim 3: To understand the relationship between DNA methylation and differential expression of genes associated with BP and HTN in the human kidney (Chapter 5). Results: In Aim 1 global DNA methylation changes were characterised in peripheral blood leukocyte and kidney DNA of the hypertensive (HT) population using he ELISA method. We found no association between HTN diagnosis and global methylation percentage in either peripheral blood leukocytes or kidney DNA. However, a negative correlation was found between global methylation and diastolic blood pressure (DBP), yet this relationship was not evident after adjustment for the effect of antihypertensive medication. Furthermore, we investigated the sensitivity of ELISA-based global methylation detection by calculating the percentage of global methylation in kidney using array based methods; the results were similar, demonstrating no association between HTN diagnosis and median kidney methylation
- Description: Doctor of Philosophy
- Authors: Wise, Ingrid
- Date: 2018
- Type: Text , Thesis , PhD
- Full Text:
- Description: Background: Hypertension (HTN) is a complex, multifactorial, quantitative trait under polygenic control that affects more than one billion people globally. Despite advances in our understanding of the pathophysiology of HTN and the implementation of more effective treatment and prevention strategies, HTN remains one of the world’s great public health problems. The accepted inference from genome-wide association studies (GWAS) is that the genetic code lays the foundation for transcriptomic changes and in turn physiological change. On the other side of the coin, environmental factors (smoking, diet, chemical exposure) can in turn affect DNA itself in genes relevant to blood pressure (BP). Variation in epigenetic forms of modification may thus explain additional phenotypic variation in BP and provide new clues to the physiological processes influencing its regulation. DNA methylation is one of these epigenetic mechanisms responsible for changes to gene expression, activated by interaction with environmental triggers. DNA methylation is a reversible epigenetic modifier of specific dinucleotide sites called CpGs, which consists of a transfer of a methyl group derived from S-adenosyl-L-methionine to position five of a cytosine ring, forming 5mC. Pathophysiologically, the kidney is known as the key organ of BP regulation and one of the most important contributors to HTN. According to the hypothesis put forward by Guyton, over 40 years ago, the control of BP in the steady-state and longer-term is critically dependent on renal mechanisms. In fact, almost all monogenic forms of HTN are driven by rare mutations in genes involved in salt handling in the distal nephron. It is therefore crucial to understand kidney DNA methylation changes that may drive gene expression in kidney and lead to HTN. Hypothesis: The central hypothesis underpinning this PhD thesis is that alterations in kidney specific DNA methylation plays a fundamental role in modulating gene expression changes involved in the regulation of BP and pathophysiology of EH. Aims: This PhD thesis focuses on characterising the role of DNA methylation in the hypertensive kidney using array and RNA-sequencing methods. Three major aims are addressed: • Aim 1: To characterise blood and kidney global DNA methylation dynamics and its functional role in the hypertensive population (Chapter 3). • Aim 2: To determine the role of genome-wide, loci specific DNA methylation in the hypertensive human kidney (Chapter 4). • Aim 3: To understand the relationship between DNA methylation and differential expression of genes associated with BP and HTN in the human kidney (Chapter 5). Results: In Aim 1 global DNA methylation changes were characterised in peripheral blood leukocyte and kidney DNA of the hypertensive (HT) population using he ELISA method. We found no association between HTN diagnosis and global methylation percentage in either peripheral blood leukocytes or kidney DNA. However, a negative correlation was found between global methylation and diastolic blood pressure (DBP), yet this relationship was not evident after adjustment for the effect of antihypertensive medication. Furthermore, we investigated the sensitivity of ELISA-based global methylation detection by calculating the percentage of global methylation in kidney using array based methods; the results were similar, demonstrating no association between HTN diagnosis and median kidney methylation
- Description: Doctor of Philosophy
Evaluating mild traumatic brain injury management at a regional emergency department
- Brown, Ashlee, Twomey, Dara, Shee, Anna
- Authors: Brown, Ashlee , Twomey, Dara , Shee, Anna
- Date: 2018
- Type: Text , Journal article
- Relation: Injury Prevention Vol. 24, no. 5 (2018), p. 390-394
- Full Text:
- Reviewed:
- Description: background: Emergency departments (EDs) are usually the first point of contact, and often the only medical service available, for patients with mild traumatic brain injury (mTBI) in rural and regional areas. Clinical practice guidelines (CPGs) have been created to ensure best practice management of mTBI in EDs. Adherence to mTBI CPGs has rarely been evaluated in rural and regional areas. Aim: The aim of this paper was to assess a regional health service's adherence to their mTBI CPG. Methods: This was a 12-month retrospective audit of 1280 ED records of patients ≥16 years presenting with mTBI to a regional Australian ED. Case selection used the Victorian Admitted Episodes Dataset codes for suspected head injury: principal diagnosis codes (S00-T98), concussive injury recorded in diagnosis codes (S06.00-S06.05) and unintentional external cause code (V00-X59). The data were collected to determine 4-hour observation rates, CT scan rates, safe discharge and appropriate referral documentation. Results: Fewer people received a CT scan than qualified (n=245, 65.3%), only 45% had 4-hour observations recorded, safe discharge was documented in 74.1% of cases and 33% received educational resources. Discussion/conclusion: Several key elements for the management of mTBI were under-recorded, particularly 4-hour observations, safe discharge and education. Acquired brain injury clinic referrals were received in overwhelmingly fewer cases than had a CT scan (n=19, 6.3%). Overall, this study suggests that the regional health service does not currently fully adhere to the CPG and that the referral services are potentially underutilised.
- Authors: Brown, Ashlee , Twomey, Dara , Shee, Anna
- Date: 2018
- Type: Text , Journal article
- Relation: Injury Prevention Vol. 24, no. 5 (2018), p. 390-394
- Full Text:
- Reviewed:
- Description: background: Emergency departments (EDs) are usually the first point of contact, and often the only medical service available, for patients with mild traumatic brain injury (mTBI) in rural and regional areas. Clinical practice guidelines (CPGs) have been created to ensure best practice management of mTBI in EDs. Adherence to mTBI CPGs has rarely been evaluated in rural and regional areas. Aim: The aim of this paper was to assess a regional health service's adherence to their mTBI CPG. Methods: This was a 12-month retrospective audit of 1280 ED records of patients ≥16 years presenting with mTBI to a regional Australian ED. Case selection used the Victorian Admitted Episodes Dataset codes for suspected head injury: principal diagnosis codes (S00-T98), concussive injury recorded in diagnosis codes (S06.00-S06.05) and unintentional external cause code (V00-X59). The data were collected to determine 4-hour observation rates, CT scan rates, safe discharge and appropriate referral documentation. Results: Fewer people received a CT scan than qualified (n=245, 65.3%), only 45% had 4-hour observations recorded, safe discharge was documented in 74.1% of cases and 33% received educational resources. Discussion/conclusion: Several key elements for the management of mTBI were under-recorded, particularly 4-hour observations, safe discharge and education. Acquired brain injury clinic referrals were received in overwhelmingly fewer cases than had a CT scan (n=19, 6.3%). Overall, this study suggests that the regional health service does not currently fully adhere to the CPG and that the referral services are potentially underutilised.
Evaluating the efficacy of an integrated motivational interviewing and multi-modal exercise intervention for youth with major depression: Healthy Body, Healthy Mind randomised controlled trial protocol
- Nasstasia, Yasmina, Baker, Amanda, Halpin, Sean, Hides, Leanne, Lewin, Terry, Kelly, Brian, Callister, Robin
- Authors: Nasstasia, Yasmina , Baker, Amanda , Halpin, Sean , Hides, Leanne , Lewin, Terry , Kelly, Brian , Callister, Robin
- Date: 2018
- Type: Text , Journal article
- Relation: Contemporary Clinical Trials Communications Vol. 9, no. (2018), p. 13-22
- Full Text:
- Reviewed:
- Description: Background Recent meta-analytic reviews suggest exercise can reduce depression severity among adults with major depressive disorder (MDD); however, efficacy studies with depressed youth are limited. Few studies have investigated the efficacy of multi-modal exercise interventions in this population, addressed treatment engagement, or explored the differential effects of exercise on depressive symptom profiles. Objectives This paper describes the study protocol and recruitment pattern for an assessor blinded, two-arm randomised controlled trial investigating the efficacy of an integrated motivational interviewing (MI) and multi-modal exercise intervention in youth diagnosed with MDD. Associations between depressive symptom profiles (cognitive, somatic and affective) and psychological, physiological (fitness), and biological (blood biomarker) outcomes will also be examined. Methods Participants aged 15–25 years with current MDD were recruited. Eligible participants were randomised and stratified according to gender and depression severity to either an immediate or delayed (control) group. The immediate group received a brief MI intervention followed by a 12-week small group exercise intervention (3 times per week for 1 h), all delivered by personal trainers. The delayed control group received the same intervention 12-weeks later. Both groups were reassessed at mid-treatment or mid-control, post-treatment or post-control, and follow-up (12 weeks post-treatment). Results 68 participants were recruited and randomly allocated to an intervention group. Conclusion This trial will increase our understanding of the efficacy of multi-modal exercise interventions for depression and the specific effects of exercise on depressive symptom profiles. It also offers a novel contribution by addressing treatment engagement in exercise efficacy trials in youth with MDD. © 2017 The Authors
- Authors: Nasstasia, Yasmina , Baker, Amanda , Halpin, Sean , Hides, Leanne , Lewin, Terry , Kelly, Brian , Callister, Robin
- Date: 2018
- Type: Text , Journal article
- Relation: Contemporary Clinical Trials Communications Vol. 9, no. (2018), p. 13-22
- Full Text:
- Reviewed:
- Description: Background Recent meta-analytic reviews suggest exercise can reduce depression severity among adults with major depressive disorder (MDD); however, efficacy studies with depressed youth are limited. Few studies have investigated the efficacy of multi-modal exercise interventions in this population, addressed treatment engagement, or explored the differential effects of exercise on depressive symptom profiles. Objectives This paper describes the study protocol and recruitment pattern for an assessor blinded, two-arm randomised controlled trial investigating the efficacy of an integrated motivational interviewing (MI) and multi-modal exercise intervention in youth diagnosed with MDD. Associations between depressive symptom profiles (cognitive, somatic and affective) and psychological, physiological (fitness), and biological (blood biomarker) outcomes will also be examined. Methods Participants aged 15–25 years with current MDD were recruited. Eligible participants were randomised and stratified according to gender and depression severity to either an immediate or delayed (control) group. The immediate group received a brief MI intervention followed by a 12-week small group exercise intervention (3 times per week for 1 h), all delivered by personal trainers. The delayed control group received the same intervention 12-weeks later. Both groups were reassessed at mid-treatment or mid-control, post-treatment or post-control, and follow-up (12 weeks post-treatment). Results 68 participants were recruited and randomly allocated to an intervention group. Conclusion This trial will increase our understanding of the efficacy of multi-modal exercise interventions for depression and the specific effects of exercise on depressive symptom profiles. It also offers a novel contribution by addressing treatment engagement in exercise efficacy trials in youth with MDD. © 2017 The Authors
Evaluating Universal Design in Built Environments – A Scoping Project
- Watchorn,Valerie, Grant, Cathryn, Tucker,Richard, Hitch, Danielle, Frawley, Patsie, Ang, Susan, Aedy, Kathryn, Gohil, Apeksha
- Authors: Watchorn,Valerie , Grant, Cathryn , Tucker,Richard , Hitch, Danielle , Frawley, Patsie , Ang, Susan , Aedy, Kathryn , Gohil, Apeksha
- Date: 2018
- Type: Text , Conference proceedings
- Relation: Universal Design and Higher Education in Transformation Congress 2018;Dublin Castle, Ireland; 30th October to 2nd November, 2018 Volume 256: Transforming our World Through Design, Diversity and Education p. 689-695
- Full Text:
- Reviewed:
- Description: This project aimed to scope existing methods of evaluating the application of universal design to built environments and to explore relevant knowledge of key stakeholders, such as architects, access consultants and people who experience disability. The project commenced in 2017. Ethics approval was gained and a mixed methods approach was employed. Methods of data collection included electronic survey and in-depth interview. Early survey findings are reported in this paper. A descriptive approach was used to analyse quantitative data. A total of 157 survey responses were received from across Australia (83%) and internationally (16.6%). Preliminary findings indicate that most survey respondents (72%) had been involved in the process of applying universal design to the design of built environments. Although evaluating the application of universal design was rated as “extremely important” by 85% of respondents, only 36% had such experience. Of these, 74% had used specific tools for this purpose. Non-standardised checklists and access audits were the most frequently used and preferred tools. Overall, stakeholders perceived themselves to have ‘some knowledge’ on universal design theory and application. This project offers insight into how universal design is understood and applied to the design of built environments. Findings suggest that evaluation is less common than application and that there is a need to strengthen existing methods of evaluation to provide greater detail on universal design processes and outcomes.
- Authors: Watchorn,Valerie , Grant, Cathryn , Tucker,Richard , Hitch, Danielle , Frawley, Patsie , Ang, Susan , Aedy, Kathryn , Gohil, Apeksha
- Date: 2018
- Type: Text , Conference proceedings
- Relation: Universal Design and Higher Education in Transformation Congress 2018;Dublin Castle, Ireland; 30th October to 2nd November, 2018 Volume 256: Transforming our World Through Design, Diversity and Education p. 689-695
- Full Text:
- Reviewed:
- Description: This project aimed to scope existing methods of evaluating the application of universal design to built environments and to explore relevant knowledge of key stakeholders, such as architects, access consultants and people who experience disability. The project commenced in 2017. Ethics approval was gained and a mixed methods approach was employed. Methods of data collection included electronic survey and in-depth interview. Early survey findings are reported in this paper. A descriptive approach was used to analyse quantitative data. A total of 157 survey responses were received from across Australia (83%) and internationally (16.6%). Preliminary findings indicate that most survey respondents (72%) had been involved in the process of applying universal design to the design of built environments. Although evaluating the application of universal design was rated as “extremely important” by 85% of respondents, only 36% had such experience. Of these, 74% had used specific tools for this purpose. Non-standardised checklists and access audits were the most frequently used and preferred tools. Overall, stakeholders perceived themselves to have ‘some knowledge’ on universal design theory and application. This project offers insight into how universal design is understood and applied to the design of built environments. Findings suggest that evaluation is less common than application and that there is a need to strengthen existing methods of evaluation to provide greater detail on universal design processes and outcomes.