ORCID Profile
0000-0002-2204-7569
Current Organisations
Oak Ridge National Laboratory
,
University of Southern Queensland
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Publisher: Cold Spring Harbor Laboratory
Date: 29-06-2023
DOI: 10.1101/2023.06.27.546742
Abstract: We present an exascale approach for producing global scale, high resolution, longitudinally based geoclimate classifications. Using a GPU implementation of the DUO Similarity Metric on the Summit supercomputer, we calculated the pairwise environmental similarity of 156,384,190 vectors of 414,640 encoded elements derived from 71 environmental variables over a 50-year time span at 1km 2 resolution. GPU matrix-matrix (GEMM) kernels were optimized for the GPU architecture and their outputs were managed through aggressive concurrent MPI rank CPU communication, calculations, and transfers. Using vector transformation and highly optimized operations of generalized distributed dense linear algebra, calculation of all-vector-pairs similarity resulted in 5.07 × 10 21 element comparisons and reached a peak performance of 2.31 exaflops. We demonstrated this method using existing and synthesized climate layers to show how geography can be parsed using high-performance computing. Geoclimate zones are important tools for understanding how environmental variables impact natural systems, particularly for agriculture and conservation with relevance to climate change. Historically, classification systems have been low resolution, based on limited variables, or subjective. To identify climate classes, we clustered DUO outputs at varying stringency, producing 69, 133, 340, and 717 global geoclimate zones. Our approach produced global scale, high resolution, longitudinally informed climate classifications that can be used in precision agriculture, cultivar breeding efforts, and conservation programs.
Publisher: Springer Science and Business Media LLC
Date: 03-11-2022
DOI: 10.1038/S41467-022-34371-W
Abstract: The discovery of functional gradients introduce a new perspective in understanding the cortical spectrum of intrinsic dynamics, as it captures major axes of functional connectivity in low-dimensional space. However, how functional gradients arise and dynamically vary remains poorly understood. In this study, we investigated the biological basis of functional gradients using awake resting-state fMRI, retrograde tracing and gene expression datasets in marmosets. We found functional gradients in marmosets showed a sensorimotor-to-visual principal gradient followed by a unimodal-to-multimodal gradient, resembling functional gradients in human children. Although strongly constrained by structural wirings, functional gradients were dynamically modulated by arousal levels. Utilizing a reduced model, we uncovered opposing effects on gradient dynamics by structural connectivity (inverted U-shape) and neuromodulatory input (U-shape) with arousal fluctuations, and dissected the contribution of in idual neuromodulatory receptors. This study provides insights into biological basis of functional gradients by revealing the interaction between structural connectivity and ascending neuromodulatory system.
Publisher: JMIR Publications Inc.
Date: 18-06-2021
DOI: 10.2196/27981
Abstract: Although evidence bolstering the efficacy of internet-based cognitive behavioral therapy (iCBT) for treating childhood anxiety has been growing continuously, there is scant empirical research investigating the timing of benefits made in iCBT programs (eg, early or delayed). This study aims to examine the patterns of symptom trajectories (changes in anxiety) across an iCBT program for anxiety (BRAVE Self-Help). This study’s participants included 10,366 Australian youth aged 7 to 17 years (4140 children aged 7-12 years 6226 adolescents aged 12-17 years) with elevated anxiety who registered for the BRAVE Self-Help program. Participants self-reported their anxiety symptoms at baseline or session 1 and then at the commencement of each subsequent session. The results show that young people completing the BRAVE Self-Help program tend to fall into two trajectory classes that can be reliably identified in terms of high versus moderate baseline levels of anxiety and subsequent reduction in symptoms. Both high and moderate anxiety severity trajectory classes showed significant reductions in anxiety, with the greatest level of change being achieved within the first six sessions for both classes. However, those in the moderate anxiety severity class tended to show reductions in anxiety symptoms to levels below the elevated range, whereas those in the high symptom group tended to remain in the elevated range despite improvements. These findings suggest that those in the high severity group who do not respond well to iCBT on a self-help basis may benefit from the additional support provided alongside the program or a stepped-care approach where progress is monitored and support can be provided as necessary.
Publisher: Cold Spring Harbor Laboratory
Date: 14-10-2021
DOI: 10.1101/2021.10.10.21264819
Abstract: The heritability of autism spectrum disorder (ASD), based on 680,000 families and five countries, is estimated to be nearly 80%, yet we lack genetic markers that adequately explain it. It is increasingly clear that genomic structural variants (SVs) are a major component of the “missing heritability” for many complex phenotypes. Here we use a novel method to identify SVs based on non-Mendelian inheritance patterns in pedigrees using parent-child genotypes from ASD families and demonstrate that the genes that the ASD-specific SVs overlap recapitulate the known molecular biology of ASD including dendritic spinogenesis, axon guidance, and chromatin modification. We further define fine-grained biological pathways that strongly implicate aberrant early development of the cerebellum. Importantly, using these previously excluded variants, we identify the ACMSD gene in the kynurenine pathway as significantly associated with non-verbal cases of ASD and we then use an explainable artificial intelligence approach to define subgroups for future diagnosis and deployment of personalized medicine.
Publisher: Public Library of Science (PLoS)
Date: 22-11-2017
Publisher: Public Library of Science (PLoS)
Date: 06-11-2018
Publisher: JMIR Publications Inc.
Date: 19-02-2018
DOI: 10.2196/JMIR.9109
Publisher: JMIR Publications Inc.
Date: 12-10-2017
Abstract: espite evidence that e-mental health services are effective, consumer preferences still appear to be in favor of face-to-face services. However, the theory of planned behavior (TPB) suggests that cognitive intentions are more proximal to behavior and thus may have a more direct influence on service use. Investigating in idual characteristics that influence both preferences and intentions to use e-mental health services is important for better understanding factors that might impede or facilitate the use of these services. his study explores predictors of preferences and intentions to access e-mental health services relative to face-to-face services. Five domains were investigated (demographics, technology factors, personality, psychopathology, and beliefs), identified from previous studies and informed by the Internet interventions model. We expected that more participants would report intentions to use e-mental health services relative to reported preferences for this type of support and that these 5 domains would be significantly associated with both intentions and preferences toward online services. mixed s le of 308 community members and university students was recruited through social media and the host institution in Australia. Ages ranged between 17 and 68 years, and 82.5% (254/308) were female. Respondents completed an online survey. Chi-square analysis and t tests were used to explore group differences, and logistic regression models were employed to explore factors predicting preferences and intentions. ost respondents (85.7%, 264/308) preferred face-to-face services over e-mental health services. Relative to preferences, a larger proportion of respondents (39.6%, 122/308) endorsed intentions to use e-mental health services if experiencing mental health difficulties in the future. In terms of the 5 predictor domains, 95% CIs of odds ratios (OR) derived from bootstrapped standard errors suggested that prior experience with online services significantly predicted intentions to use self-help (95% CI 2.08-16.24) and therapist-assisted (95% CI 1.71-11.90) online services in future. Being older predicted increased intentions to use therapist-assisted online services in future (95% CI 1.01-1.06), as did more confidence using computers and the Internet (95% CI 1.06-2.69). Technology confidence was also found to predict greater preference for online services versus face-to-face options (95% CI 1.24-4.82), whereas higher doctor-related locus of control, or LOC (95% CI 0.76-0.95), and extraversion (95% CI 0.88-1.00) were predictive of lower likelihood of preferring online services relative to face-to-face services. espite generally low reported preferences toward e-mental health services, intentions to access these services are higher, raising the question of how to best encourage translation of intentions into behavior (ie, actual use of programs). Strategies designed to ease people into new Internet-based mental health programs (to enhance confidence and familiarity) may be important for increasing the likelihood that they will return to such programs later.
Publisher: Elsevier BV
Date: 2023
Publisher: Springer Science and Business Media LLC
Date: 02-02-2017
Publisher: Elsevier BV
Date: 10-2014
DOI: 10.1016/J.BRAT.2014.08.002
Abstract: The aim of this study was to provide a preliminary examination of a disorder-specific treatment program for children with generalised anxiety disorder (GAD) that employed strategies targeting underlying cognitive factors. Forty-two children with a primary diagnosis of GAD, aged between 7 and 12 years, were randomly assigned to either a treatment (TX) or waitlist (WLC) condition. Clinical diagnostic interviews as well as parent and child questionnaires were completed at pre- and post-assessment for both conditions, and at 3-month follow-up for the TX group. For the completer analyses at post-treatment, 52.9 % of children in the TX group (0% in the WLC group) were free of their primary GAD diagnosis. By 3-month follow-up, 100% of children in the TX group were free of their GAD diagnosis, 50% were free of all diagnoses. Overall, there is preliminary evidence that a disorder-specific treatment program for children with GAD is effective in treating this chronic and disabling disorder.
Publisher: Cold Spring Harbor Laboratory
Date: 25-04-2022
DOI: 10.1101/2022.04.20.22273895
Abstract: Genome-wide association studies (GWAS) identify genetic variants underlying complex traits but are limited by stringent genome-wide significance thresholds. Here we dramatically relax GWAS stringency by orders of magnitude and apply GRIN (Gene set Refinement through Interacting Networks), which increases confidence in the expanded gene set by retaining genes strongly connected by biological networks from erse lines of evidence. From multiple GWAS summary statistics of suicide attempt, a complex psychiatric phenotype, GRIN identified additional genes that replicated across independent cohorts and retained genes that were more biologically interrelated despite a relaxed significance threshold. We present a conceptual model of how these retained genes interact through neurobiological pathways to influence suicidal behavior and identify existing drugs associated with these pathways that would not have been identified under traditional GWAS thresholds. We demonstrate that GRIN is a useful community resource for improving the signal to noise ratio of GWAS results.
Publisher: Springer International Publishing
Date: 23-11-2018
DOI: 10.1007/102_2018_2
Abstract: In this review, we provide evidence to suggest that the cost of specific mtDNA mutations can be influenced by exogenous factors. We focus on macronutrient-mitochondrial DNA interactions as factors that may differentially influence the consequences of a change as mitochondria must be flexible in its utilization of dietary proteins, carbohydrates, and fats. To understand this fundamental dynamic, we briefly discuss the energy processing pathways in mitochondria. Next, we explore the mitochondrial functions that are initiated during energy deficiency or when cells encounter cellular stress. We consider the anterograde response (nuclear control of mitochondrial function) and the retrograde response (nuclear changes in response to mitochondrial signaling) and how this mito-nuclear crosstalk may be influenced by exogenous factors such as temperature and diet. Finally, we employ Complex I of the mitochondrial electron transport system as a case study and discuss the potential role of the dietary macronutrient ratio as a strong selective force that may shape the frequencies of mitotypes in populations and species. We conclude that this underexplored field likely has implications in the fundamental disciplines of evolutionary biology and quantitative genetics and the more biomedical fields of nutrigenomics and pharmacogenomics.
Publisher: Wiley
Date: 14-11-2020
DOI: 10.1111/APHW.12182
Abstract: Given the substantive health inequalities in peri-urban communities and the potential for physical activity to promote health in these communities, identifying modifiable physical activity determinants in this population is important. This study explored effects of the peri-urban environment and psychological constructs on physical activity intentions and behavioural automaticity guided by an integrated theoretical framework. Peri-urban Australians (N = 271) completed self-report measures of environmental (i.e. physical/social environment, and neighbourhood selection), motivational (i.e. autonomous motivation), and social cognition (i.e. attitudes, norms, and perceived behavioural control [PBC]) constructs, past behaviour, intentions, and automaticity. A well-fitting path analytic model revealed that: autonomous motivation predicted all social cognition constructs subjective norms and PBC, but not attitudes autonomous motivation predicted intentions and automaticity and subjective norms and PBC mediated effects of autonomous motivation on intentions. Of the environmental constructs, only neighbourhood selection was related to intentions, mediated by PBC. Autonomous motivation is an important correlate of physical activity intentions and automaticity, and subjective norms and PBC also related to intentions. In iduals perceiving a supportive environment were more likely to report positive PBC and intentions. Targeting change in autonomous motivation, and normative and control beliefs may help enhance physical activity intentions and automaticity in peri-urban communities.
Publisher: JMIR Publications Inc.
Date: 16-02-2021
Abstract: lthough evidence bolstering the efficacy of internet-based cognitive behavioral therapy (iCBT) for treating childhood anxiety has been growing continuously, there is scant empirical research investigating the timing of benefits made in iCBT programs (eg, early or delayed). his study aims to examine the patterns of symptom trajectories (changes in anxiety) across an iCBT program for anxiety (BRAVE Self-Help). his study’s participants included 10,366 Australian youth aged 7 to 17 years (4140 children aged 7-12 years 6226 adolescents aged 12-17 years) with elevated anxiety who registered for the BRAVE Self-Help program. Participants self-reported their anxiety symptoms at baseline or session 1 and then at the commencement of each subsequent session. he results show that young people completing the BRAVE Self-Help program tend to fall into two trajectory classes that can be reliably identified in terms of high versus moderate baseline levels of anxiety and subsequent reduction in symptoms. Both high and moderate anxiety severity trajectory classes showed significant reductions in anxiety, with the greatest level of change being achieved within the first six sessions for both classes. However, those in the moderate anxiety severity class tended to show reductions in anxiety symptoms to levels below the elevated range, whereas those in the high symptom group tended to remain in the elevated range despite improvements. hese findings suggest that those in the high severity group who do not respond well to iCBT on a self-help basis may benefit from the additional support provided alongside the program or a stepped-care approach where progress is monitored and support can be provided as necessary.
No related grants have been discovered for Michael Garvin.