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NZDep2018 analysis of census 2018 variables - TA012: Hauraki District
No full textFor further information about data sources, interpretation of the graphs, and cautions, please see the separate Introduction Chapter
All data relating to the 2018 census is provided by Stats NZ, https://www.stats.govt.nz/
Scapular dyskinesis and subacromial shoulder pain
No full textAbstract
Background: Subacromial shoulder pain is a common cause of pain in patients with shoulder complaints. Changes in scapular rotations, termed scapular dyskinesis, have been hypothesized to contribute to the etiology and maintenance of subacromial shoulder pain. The overall aim of this thesis was to add towards understanding of the potential role of scapular dyskinesis in the recovery of subacromial shoulder pain. For this purpose, we assessed: 1) the changes in pain and function scores over time in patients with subacromial shoulder pain; 2) the association between changes in pain or function scores and changes in scapular dyskinesis; and 3) the feasibility of conducting a randomized control trial (RCT) to compare the efficacy of tailored training program with standardized exercise program on improving pain, function and scapular dyskinesis in patients with subacromial shoulder pain.
Methods and results: A systematic review and meta-analysis (Study 1) was conducted to assess the clinical course of pain and function in patients with subacromial shoulder pain who received ‘no intervention’ and ‘usual care’. The results showed patients with ‘no intervention’ reported no changes in pain and function scores over 3 months (maximum follow-up was to 3 months) and patients receiving ‘usual care’ reported an average 30 scores improvement (score ranging from 0 to 100) in pain and function at 12 months with 40% of that improvement occurring in the first 6 weeks from the study entry (maximum follow-up was to 12 months).
Next, the association between changes in pain or function scores was assessed with changes in scapular dyskinesis. For conducting this, first, a laboratory-based study assessed the intra-rater between-day reliability of scapular locator for measuring scapular rotations during scapular plane arm elevation in asymptomatic individuals (Study 2). Findings suggested that the scapular locator has a good to excellent reliability for measuring scapular upward/downward rotation and anterior/posterior tilt (ICC ranging from 0.73 to 0.93) of arm at 60, 90 and 120 arm elevation and a poor reliability for measuring scapular internal/external rotation (ICC ranging 0.37 to 0.62). The results also indicated a poor reliability for measuring all scapular rotations at 30 of arm elevation (ICC = 0.10 to 0.40). The findings of this study supported the use of the scapular locator for measuring scapular upward/downward rotation and anterior/posterior tilt in the subsequent observational study. The observational study assessed the association between changes in pain or function scores with changes in scapular rotations (measured with scapular locator and scapular dyskinesis test) in patients with subacromial shoulder pain, over an 8-week period (Study 3). The results showed changes in pain or function scores are not associated with changes in scapular rotations.
Finally, a feasibility RCT (Study 4) assessed the feasibility of conducting a full RCT to investigate the efficacy of a tailored training program compared with a standardized exercise program in participants with subacromial shoulder pain. Twenty-eight participants with subacromial shoulder pain (aged 18-65 years) were recruited during 41 weeks and were randomly allocated to tailored training (N=13) or standardized exercise (N=15) programs for 8 weeks. Participants in each group were assessed for pain, function and scapular dyskinesis at week 4 and 8 from baseline. The findings showed that it is feasible to conduct a full RCT with the recruitment rate of 3 participants per month, the proportion of eligible participants per participants screened was 23%. The adherence rate was 86.6% for physiotherapist-delivered interventions and 93.1% for home-based exercises. The drop-out rate was 14% (4 participants out of 28 enrolled). The preliminary analysis suggested significant improvements in pain, function in both groups and significant improvement in scapular dyskinesis in the tailored training group. No between-group differences were observed in above outcome measures at 4 and 8 weeks. Based on between-group mean differences in pain and considering a 20% drop-out rate, a total of 88 participants (44 participants in each group) are required for conducting a full RCT.
Conclusion This thesis provided a summary of expected changes in pain and function over time for patients receiving ‘no intervention’ or ‘usual care’. These findings could be used as a reference for future researchers when designing new studies or by clinicians when managing patients. Our findings on the association between changes in pain or function with scapular rotations did not support the contributing role of scapular dyskinesis in subacromial shoulder pain. However, further studies are required to confirm our findings given challenges with scapular measurements. We also suggest assessing whether other factors (e.g., age, shoulder pain duration, physical functioning, and comorbidity) may be confounding variables when assessing the association between scapular dyskinesis and subacromial shoulder pain. Findings from the feasibility RCT suggested it is possible to conduct a full RCT. The full RCT will explore whether a tailored training program leads to better clinical outcomes (e.g. pain, function and scapular dyskinesis) when compared with a standardized exercise program
New Zealand Deprivation Index 2018 - TA57: Westland District
No full textFor further information about data sources, interpretation of the graphs, and cautions, please see the separate Introduction Chapter
All data relating to the 2018 census is provided by Stats NZ, https://www.stats.govt.nz/
New Zealand Deprivation Index 2018 - TA67: Chatham Islands Territory
No full textFor further information about data sources, interpretation of the graphs, and cautions, please see the separate Introduction Chapter
All data relating to the 2018 census is provided by Stats NZ, https://www.stats.govt.nz/
New Zealand Deprivation Index 2018 - TA76: Auckland
No full textFor further information about data sources, interpretation of the graphs, and cautions, please see the separate Introduction Chapter
All data relating to the 2018 census is provided by Stats NZ, https://www.stats.govt.nz/
Ensemble learning through cooperative evolutionary computation
No full textBuilding ensembles of classifiers is an active area of research for machine learning, with the fundamental goal of combining the predictions of multiple classifiers to improve prediction accuracy over an individual classifier. In theory, combining classifiers in an ensemble can improve the prediction results by compensating for individual classifier weaknesses in certain areas by benefiting from better accuracy of the other individuals in the same area. Typical ensemble learning approaches require extensive amounts of computation to train and combine multiple models into a single solution. A key question in ensemble learning is: given the total computational effort roughly equivalent to a single monolithic solution, can an ensemble learner achieve comparable or better performance?
In this thesis, a comparison is made between a single complex monolithic agent and an ensemble of many simpler agents that is evolved using equivalent computational effort. To do this, a framework is constructed that enables the comparison of a monolithic approach using complex agents, and an ensemble approach made up of simple agents. This is then applied to the application of buying and selling stocks on a simulated stock market and comparing the results of the two approaches to classify stock data on when to buy and sell. The framework involves creating a population of agents. These are “decision making agents” (DMAs), which evaluate a data source and decide at each time step whether to trade or hold a stock.
In many learning problems, such as the stock trading example used in this thesis, the suitability of a model is measured at a macroscopic level aggregated over multiple decision actions. These problems are not well-suited to traditional learning methods, so evolutionary computation (EC) is frequently used to build machine learning models in these situations. Historically, most EC approaches use a single population to evolve a single solution. A more recent branch of EC research emphasises the use of cooperative coevolution, where the required solution is decomposed into several sub-components, and multiple populations are used in parallel to simultaneously evolve these. There are strong analogies between the divide and conquer strategies of cooperative co-evolution and the building of ensembles in traditional machine learning.
In this thesis, a cooperative co-evolution approach using genetic programming to evolve individual populations and combined them as an ensemble is used to evolve a solution. The agents in the individual populations are evolved with a standard genetic programming approach, where our DMAs are decision trees made up of logic operators (function primitives) and stock indicators (terminal primitives). DMAs are used for both monolithic and ensemble algorithms, but the size of the DMAs varies and the way they are evaluated is different. With the monolithic approach only a single population is used, but the agents in the population evolve to have increased complexity compared to the agents in the ensemble approach. With the cooperative co-evolution ensemble approach, n populations are created and evolved independently, but they are evaluated together using majority voting. The agents used in the ensemble approach are only allowed 1/n of the nodes that the monolithic agent can have, reducing the ensemble’s total complexity to a similar level to that of the monolithic approach.
With this framework, this thesis suggests that an ensemble of simple agents using variance reduction performs as well, and in most cases better than, a complex monolithic agent. The variance reduction process is like that of bagging, with majority voting within the ensemble damping down the behaviour of over-active, risky models to reduce the error component attributable to these risky actions. This variance reduction behaviour was not by design, but was an emergent property. The robustness of these findings is examined under multiple conditions, which include key parameters pertaining to ensemble learning. These include population size and ensemble size, which are examined in this work to gain insights into an optimal set of parameter values.
To ensure that the insights into ensemble learning generalise beyond that of the examined stock trading problem, an alternative unrelated problem, suitable for a cooperative approach is then tested in a similar way. This is the Tartarus problem, in which agents use finite state machines (FSM) for internal states. Previous work in using cooperative co-evolutionary methods on the Tartarus problem focused on decomposition of a single FSM and met with limited success. The co-evolutionary approach used here builds an ensemble of smaller FSMs, each voting on the best action to take. This configuration reduces the computational effort in the mutation operator, therefore allowing an ensemble with more total states to be used for the same overall computational effort. In this context, this approach improves on previous cooperative research and shows that some findings are transferable between applications when using the ensemble approach shown in this research
Does Size Matter? Using Osteology and Ancient DNA to Reconstruct Extinct Diversity in Duvaucel’s Gecko
No full textThe dynamic geology and climate of the New Zealand archipelago has had pronounced effects on the evolution of its endemic flora and fauna. However, contemporary biodiversity is depauperate, with previous studies revealing complex extinction-recolonization dynamics and cryptic extinctions following both Polynesian and European arrival. Hoplodactylus duvaucelii (Duvaucel’s gecko) is a large Diplodactylidae species, previously widespread throughout New Zealand (based on relative-size identification of Holocene subfossils), with extant populations restricted to predator-free offshore islands. This thesis uses integrated morphological and genetic approaches to reconstruct the taxonomic and phylogeographic diversity of New Zealand’s large geckos (‘H. cf. duvaucelii’) prior to Polynesian and European arrival. Geometric morphometrics (of three-dimensional micro-CT scans) was used to characterise and describe maxillae shape and size variation between extant genera (Dactylocnemis, Hoplodactylus, Mokopirirakau, Naultinus and Woodworthia), and to determine the taxonomic affinities of Holocene ‘H. cf. duvaucelii’ subfossils. All genera were morphologically distinct, with shape variation in the nasal and orbital margins primarily reflecting ecomorphological adaptation. However relative-size comparisons were only effective in distinguishing Hoplodactylus. Additionally, while some ‘H. cf. duvaucelii’ subfossils exhibited strong affinities towards H. duvaucelii, others possessed morphological variation not encompassed by extant representatives. Furthermore, ancient mitochondrial genomes recovered from Holocene ‘H. cf. duvaucelii’ subfossils using a minimally destructive DNA extraction method, were used to test for cryptic extinctions of large Holocene geckos, and to reconstruct phylogeographic structure in H. duvaucelii. All recovered ancient mitochondrial genomes were identified as H. duvaucelii, confirming their once widespread mainland distribution. Absence of large Holocene representatives outside Hoplodactylus implies gigantism evolved only once within the New Zealand Diplodactylidae radiation. Pronounced phylogeographic structure was identified within H. duvaucelii, with extant populations comprising two deeply divergent and morphologically distinct species: H. duvaucelii ‘North’ and H. duvaucelii ‘South’. This thesis provides the most comprehensive study of New Zealand’s Holocene subfossil geckos and highlights the applications of integrated geometric morphometric and ancient DNA analyses in taxonomy, biogeography and conservation of understudied fauna
Development of hydrogel-based strategies for tissue vascularisation
No full textThe tissue engineering field and regenerative medicine has emerged as a promising strategy to overcome the lack of availability of organs and tissue grafts for transplantation. One of the main challenges in the field is to generate tissue analogues of relevant size with adequate nutrient and oxygen supply that promote graft integration and long-term functionality. The main strategies to promote tissue vascularisation are to either deliver bioactive cues such as growth factors (GFs), which attract the host vessels towards the area of interest, or to directly generate tissue analogues including a vessel network that can anastomose with the host blood vessels after implantation.
This thesis aims to develop novel platforms to improve tissue vascularisation by delivering GFs and generating in vitro vascularised tissues. Firstly, a literature review summarises the main strategies to deliver GFs and to generate in vitro vascularised tissues, together with their present limitations for clinical translation. Next, a GF delivery system based on tyraminated poly(vinyl alcohol) (PVA-Tyr) is developed, which has the ability to covalently incorporate a range of native GFs and then release them in a controlled profile and during a tailorable time frame. The flexibility of this GF delivery system allowed its adaptation to the revascularisation of the femoral head in an in vivo model of avascular necrosis, which was done by adjusting the incorporated GF, the GF release time, the cell-material interactions of the system and its delivery method. This research is followed by the development of a gelatin-norbornene (Gel-NOR) platform that allows biofabrication of large vascularised tissues. The fabricated tissues combined a controllable pore structure, which mimicked larger vessels in native tissues, with encapsulated endothelial cells that were able to assemble into micro-capillary structures, mimicking the capillary beds in native tissues. These fabricated tissues were used as a model to study how design parameters can affect the behaviour of endothelial cells, demonstrating that pore diameter and fibre diameter could have an impact on the ability of endothelial cells to form micro-capillaries. Finally, the developed platforms were combined using bioassembly, which allowed understanding how different cell arrangements can affect endothelial cell behaviour within fabricated scaffolds and to develop tissue analogues that combine GF delivery with pre-vascularisation techniques. Overall, this thesis combines materials chemistry and design with advanced fabrication techniques to develop new strategies that address current limitations in the field of tissue vascularisation
State history and political instability: The disadvantage of early state development
No full textThis paper establishes that long-term exposure to statehood is detrimental to building politically stable regimes outside Europe. It argues that accumulated statehood experience impeded the diffusion of European institutions and was conductive to the early emergence of powerful elites, leading to contemporary institutional stagnation. This undermines the provision of public goods and lowers the opportunity cost of engaging in riots, arguably giving rise to socio-political unrest. Using data for 109 non-European societies, the study documents evidence that a long history of statehood is linked to the persistence of political instability. The main findings withstand numerous robustness analyses
Micropatterned Aluminium Surfaces for Anti-icing and Anti-frosting Applications
No full textDeveloping anti-icing and anti-frosting technology is vital for many different energy generation and consumption systems such as wind turbines, aircraft and heat exchangers, where ice and frost formation is a barrier for efficiency and can severely damage infrastructure and injure people.
This work investigates anti-icing and anti-frosting properties of aluminium hierarchical structures with varying geometric parameters. These structures consisted of micro-milled microstructures with nanoscale roughness due to the milling. Fixed-pitch and gradient-pitch structures were tested, the latter of which have not been tested for ice adhesion previously. The structures are characterised for their geometric and surface wetting properties using a scanning electron microscope and a goniometer respectively, then tested for anti-icing properties using a force probe and anti-frosting properties using a wind tunnel with Peltier cooling. Both systems were custom built for this purpose.
These aluminium surfaces rely only on topographic modifications - no lubricants, coatings or polymers, which tend to be prone to damage and impractical to reapply in many applications. It was found that these gradient-pitch microstructures had equivalent or better anti-icing/anti-frosting performance than the fixed-pitch structures for both ice adhesion and frosting delay