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Utilising concept-based instruction in teaching pragmatics: Exploring the development of requesting behaviour of Iraqi Arabic-speaking EFL learners
No full textThis thesis explores the effect of concept-based pragmatic instruction (CBPI) in developing Iraqi Arabic-speaking EFL university students’ conceptual knowledge and performance abilities in English requests. Requests have been one of the most investigated features in interventional pragmatic studies. However, the majority of the interventional studies take forms as the point of departure in their treatment and focus less on meaning. In contrast, this study takes meaning as the focus and the point of departure in its treatment by utilising CBPI. Drawing from Vygotsky’s sociocultural theory, CBPI is based on three main principals: concepts as the minimal units of instruction, materialisation of concepts through didactic models (e.g., diagrams), and verbalisation to internalise the concepts. The main aim of the study was to examine the learners’ sociopragmatic and pragmalinguistic conceptual development. A secondary aim was to examine how learners of different proficiency levels would respond to CBPI.
The learners were 9 high intermediate (HIL) learners and 8 elementary (EL) learners. The intervention involved a 5-session course, in addition to one pre-test session and one post-test session. The intervention was designed around the principles of concepts, materialisation, and verbalisation. The principles formed the basis of CBPI cards (adapted from van Compernolle, 2012), which oriented learners and helped them materialise and verbalise the concepts. Learners engaged in video-based language analysis tasks, scenario performances, and contextualized request analyses. Development was assessed through pre- and post-interviews, scenarios, and appropriateness judgement questionnaires (AJQs), as well as scenarios within the intervention course that allowed development to be assessed as it happened. Data were analysed qualitatively by comparing pre- and post-test data and conducting a microgenetic analysis of scenarios.
Results showed 1) marked development in the learners’ conceptual understanding of the sociopragmatic and pragmalinguistic resources, 2) some notable development in the learners’ performance abilities, although not as much as in their conceptual understanding, and 3) no major differences between the two proficiency groups in the interview data.
Most learners showed development, but the AJQ and scenario data showed a clear advantage of HIL learners over EL learners, suggesting that higher proficiency learners benefit more from CBPI. This difference could be attributed to several factors including the linguistic and cultural distance between English and Arabic and the fact that each learner has his/her unique ZPD and development trajectory. The study contributes to the literature by expanding the applicability of CBPI in pragmatics to teaching requests to Arabic-speaking learners of English. Finally, this thesis calls for future research to explore how other learners whose L1 is distant from their L2 respond to CBPI, especially for other speech acts
Effectiveness of exercise in blood pressure management in adults diagnosed with true resistant hypertension and obstructive sleep apnoea
No full textBackground
Resistant hypertension is a special phenotype within hypertension which may remain uncontrolled despite pharmacological management. Adults with resistant hypertension have increased risk of cardiovascular mortality and morbidity. Further, resistant hypertension has a bidirectional relationship with obstructive sleep apnoea and the two compound each other. International hypertension guidelines recommend exercise as a therapeutic modality to manage hypertension but studies that have investigated the effectiveness of exercise in the management of resistant hypertension are limited and have not previously been undertaken on a New Zealand population.
Aim
The main aim of the thesis was to investigate the 24 hour blood pressure change in response to an exercise programme in individuals diagnosed with true resistant hypertension and at risk of obstructive sleep apnoea. The secondary aims were firstly, to provide evidence for the effectiveness of blood pressure change in response to exercise in cohorts with resistant hypertension; secondly, to determine the prevalence of true resistant hypertension in individuals diagnosed with resistant hypertension and investigate the association of resistant hypertension with obstructive sleep apnoea; and thirdly, for individuals living with resistant hypertension, to explore their perception of exercise as a therapeutic modality for their condition.
Methods
This mixed-method thesis includes quantitative and qualitative methodologies. A narrative review was undertaken to explore the potential role of exercise as a therapeutic modality to manage blood pressure in hypertension. The narrative review lead to the investigation of effectiveness of physical activity and exercise in blood pressure management in resistant hypertension in a systematic review. The descriptive observational study on prevalence of true resistant hypertension and association with obstructive sleep apnoea risk was followed by a single group pre- post-test trial. The qualitative study with individuals living with resistant hypertension was conducted as a standalone study with an inductive approach with thematic analysis.
Results
The narrative review showed that the current guidelines recommended physical activity and exercise as a therapeutic modality in management of hypertension. The systematic review confirmed that physical activity (mean differences; systolic -9.88 mmHg, 95% CI: -17.62 to -2.14/ diastolic -6.24 mmHg, 95% CI: -12.65 to 0.17), in particular aerobic exercise (mean differences; systolic -12.06 mmHg, 95% CI: -21.14 to -2.96 / diastolic -8.19 mmHg, 95% CI: -14.83 to -1.55) was clinically effective in reducing blood pressure in resistant hypertension when the mean differences of experimental and controlled groups were considered. A clinically meaningful blood pressure reduction in response to exercise was identified in pre and post-test measurements (systolic -10.14 mmHg, 95% CI: -17.04 to - 3.24 / diastolic -3.80 mmHg, 95% CI: 5.95 to 1.65) for experimental groups in published randomised control trials. The observational study reported that 22 of the 25 participating adults had true resistant hypertension (88%). Nineteen (19) of 22 with true resistant hypertension were at high risk for obstructive sleep apnoea (86%) when standardized questionnaires were used. The intervention study reported there was clinically meaningful blood pressure reduction (mean differences; systolic -6.43±11.94 mmHg, 95% CI -17.47 to 4.62/ diastolic -4.00±8.94 mmHg, 95% CI: -12.27 to 4.27) in the post-study group. However, the changes were not statistically significant. Qualitative study results suggested that the health literacy of the individuals living with resistant hypertension was low. Participants’ perceptions were mixed regarding the potential role of exercise as a therapeutic modality to manage their blood pressure.
Conclusions
The thesis confirmed that physical activity, in particular, aerobic exercise, is an effective therapeutic modality to manage blood pressure and improve sleep quality in a cohort with resistant hypertension and obstructive sleep apnoea risk. The prevalence of true resistant hypertension was high amongst participants with apparent resistant hypertension. Further, the risk of obstructive sleep apnoea may strongly be associated with the condition as higher percentage of participants had obstructive sleep apnoea risk. Exercise may be recommended as a non-pharmocological approach in management of adults with resistant hypertension and obstructive sleep apnoea risk. Health literacy needs to be improved for individuals living with resistant hypertension to empower them to take responsibility for the management of their condition. Fully powered studies need to be conducted to confirm the results from the quantitative studies piloted in this thesis. Careful consideration should be taken for recruitment to be inclusive of high risk population groups e.g. Māori, South Asians and with comorbidities e.g. chronic kidney diseases (CKD)
A Computational Model of Transduction Cells in the Vestibular System
No full textThe human brain, and even the brains of the lowest vertebrates, are diabolically complex, and complete understanding of these systems would take hundreds of careers to build. One key way of dealing with this complexity is to look back in time, and study the evolution of neurons and brains. This allows researchers to investigate the selection pressures driving the evolution of the brain, and how these influenced its development. Another method is to study simple parts of the brain, figure out how they work, and see if this can be generalised to other brain regions.
The vestibular system, responsible for detection of head acceleration, is of particular interest due to its early evolution, and the simplicity of its role of dynamical inference. Constructing computational models of cells involved in vestibular transduction provides a framework which can be used by researchers to test and extend understanding of how the system works.
This thesis describes work building a computational model of the transduction cells of the vestibular system, known as hair cells, and extension of the model to include the firing of vestibular afferent neurons. All modelling was carried out using the Julia programming language.
The model of a vestibular hair cell built somewhat replicated the behaviour of biological hair cells, however, further refinement or experimentation is necessary to accurately reproduce the characteristics of any single hair cell. A concerning discovery was that the range of parameter values reported for hair cells in the literature, using state of the art modelling frameworks, was unable to replicate thirty two percent of the observed range of resting membrane potentials of these cells.
The extension of the model used scaled calcium concentration of a resting hair cell, which fluctuates due to Brownian motion of the transduction apparatus, as input for a leaky integrate-and-fire neuron. It was found that this input could be scaled to reproduce the diverse statistical distributions of resting discharge observed in vestibular afferent neurons.
Together, my studies provide improved documentation and reporting of vestibular hair cell models, directions for future research, and an interesting first model including both vestibular hair cells and vestibular afferent neurons
Lenore Divine
No full textLenore Divine follows the romantic and political adventures of the title character and her friend Lafe Osgood. Will Lenore find happiness with dissolute Holly Virtue or with Waikato farmer Kowhatu Ngatoro? Can Lafe redeem his flapper fiancee from her hedonistic jazz lifestyle? Will the Labour Party achieve political power and influence? Can women find contentment in marriage or will a free love union bring more autonomy and sexual satisfaction
Role of CaMKII and Alpha Stimulation in Heart Function
No full textCardiovascular disease is a major cause of morbidity and mortality in New Zealand. Elucidating its pathogenesis will help us better treat those who are affected by it. One protein that has been implicated in cardiovascular pathology is Calcium (Ca2+)/Calmodulin-dependent protein Kinase II (CaMKII). As its name suggests, it is activated by Ca2+-bound calmodulin. In a healthy heart, CaMKII plays a role in regulating Ca2+-handling proteins in the cardiomyocyte, such as Ryanodine Receptor and Phospholamban. CaMKII has the ability to become autonomously activated so that it can exert its effects even when the Ca2+ concentration decreases. However, if CaMKII is activated when it does not need to be, it can have pathological effects. It can be activated pathologically by hyperglycemia, oxidative stress and hyperadrenergic states, all of which are seen in cardiovascular pathology such as heart failure or diabetic cardiomyopathy. Alpha-adrenergic receptor signaling can also activate CaMKII, but little is known about the effects of alpha-adrenergic stimulation on the heart.
The aim of this project was the determine the functional effects of the alpha-adrenergic agonist Methoxamine on isolated wild-type mouse hearts, and in isolated CaMKII knockout mouse heart, in incremental doses to observe differences in the responses between the two groups to determine the role of CaMKII in the functional response to alpha-adrenergic stimulus in the heart.
The technique used to address these aims was the isolated heart set-up, which is also known as the Langendorff setup. The mouse hearts were surgically removed from the animal, with part of the aorta intact, and placed in an arresting buffer with a high potassium chloride concentration to ionically arrest the heart. The heart was then cannulated via the aorta, and perfused with a Krebs-Henseleit Buffer (KHB) that had all the necessary ions and nutrients to allow the heart to contract outside the body. The stability of the heart was determined via measurements such as coronary flow rate, perfusion pressure, and temperature. A fluid-filled balloon inserted into the ventricle allowed measurement of contractile and relaxation parameters. Increasing doses of alpha-adrenergic receptor agonist, Methoxamine, were added to the KHB perfusate. Three doses were used; 10-8, 10-6, and 10-4mmol/L.
I found that in response to alpha-adrenergic stimulation, there was a significant increase in the rate of contraction (1.384-fold increase; p= 0.0114) and the rate of relaxation (1.435-fold increase; p= 0.0066) in the healthy, wild-type mouse hearts, but not in the CaMKII knockout mouse hearts (rate of contraction- 1.167-fold change; p=0.5080; rate of relaxation- 1.156-fold change; p= 0.5862). There was a significant increase in the total developed pressure in the heart during systole in the healthy mouse hearts in response to alpha-adrenergic stimulation (1.407-fold increase; p= 0.0206), but this increase was not seen in the CaMKII knockout mice (1.099-fold change; p= 0.8750). There was also a significant reduction in the minimum pressure reached by the heart, and the end-diastolic pressure in the healthy wild-type mouse hearts in response to alpha-adrenergic stimulation. Again, this change was not seen in the CaMKII knockout mouse hearts.
The results show that CaMKII may be responsible for the regulation of some contractile and relaxation parameters in the heart. By phosphorylation of its target protein, Ryanodine Receptor, CaMKII can increase the amount and rate of Ca2+ release into the cytoplasm of the cardiomyocyte which would allow for faster and more robust contractions. Furthermore, by phosphorylating Phospholamban, CaMKII can increase the rate and amount of Ca2+ cleared from the cytoplasm of the cardiomyocyte which would allow for faster and better relaxation. The results also tell us that CaMKII may be party of the alpha-adrenergic signaling pathway.
Future research into the involvement of alpha-adrenergic signaling in cardiovascular pathology, and whether inhibiting CaMKII attenuates or completely ablates disease progression will allow us to target CaMKII or the alpha-adrenergic signaling pathway as a therapeutic for cardiovascular disease
An Inter-Species Investigation into the Role of Cytochrome c in Apoptosis
No full textCytochrome c is a protein that has important roles in electron transport and cell death (apoptosis). In its role during the intrinsic apoptosis pathway, cytochrome c is released from the mitochondria for it to interact with the cytosolic protein Apaf-1 at its WD40 domain. The binding event between cytochrome c and Apaf-1 triggers the formation of the heptameric apoptosome which activates caspase enzymes for cell death. The first naturally occurring mutation in cytochrome c, characterised as a substitution of glycine to serine at position 41 (G41S), was identified in a New Zealand family with inherited thrombocytopenia. This mutation was found to cause an increase in the ability of human cytochrome c to activate caspases. The same G41S mutation when introduced into mouse cytochrome c exhibited the opposite effect with a decrease in caspase activation compared to mouse wildtype. The molecular mechanisms that underly these species-specific effects of the G41S mutation are unknown, though the dynamics of the 40-57 Ω-loop has been suggested to play a role. This thesis reports analysis of molecular dynamics simulations of mouse WT and G41S cytochrome c compared against human WT and G41S cytochrome c simulation data. Characterisation of the global stabilities of mouse and human cytochrome c variants and trialled expression of a Apaf-1 WD40 domain construct are also reported.
Expression trials of the Apaf-1 WD40 domain construct ∆N594 in insect cell lines showed high expression but little solubility upon purification. Future work involving the redesign of a WD40 domain construct will be required to achieve a useable construct for investigating the interaction of Apaf-1 with cytochrome c. Molecular dynamics simulations of mouse WT and G41S cytochrome c showed no clear difference in mobility to human WT cytochrome c with these three variants not exhibiting any large conformational shifts. Human G41S shows a large increase in mobility, especially in the 40-57 Ω-loop region, over that of human WT cytochrome c. This indicates species-specific effects of the G41S mutation on mobility. Analysis of the global stabilities of WT and G41S cytochrome c of each species showed there is no difference in Tm. Human WT, mouse WT and mouse G41S exhibited the same thermodynamic parameters. Human G41S however showed a decrease in enthalpy and increase in entropy, much lower than the other three variants, indicating hG41S has a more disordered native structure. This aligns with the observations from the molecular dynamics simulations. It is likely that the increased mobility of human G41S may explain the increase in caspase activation seen with this variant. However, the dynamics do not explain the decrease in caspase activation seen with mouse G41S. Species variation in the WD40 domain of Apaf-1 may play a role in determining this effect, where mouse and human Apaf-1 may allow different ranges of mobility for interacting residues on cytochrome c to achieve tight binding
Super Hydrophilic Wool based Biomaterial for Wound Dressing Application
No full textThe development of new, innovative, and sustainable biomaterials to be used for
wound dressing application is a current field of research gaining a lot of attention
in the biomedical (healthcare) industry. The current global market cap for topical
wound dressings as of 2020 is USD $11.4 billion dollars with an annual growth
rate of 4.4% since 2015. With the world population swelling to all-time highs year
after year, a push for natural, sustainable materials to be used in wound dressings
is necessary. Sheep’s wool is a 100% natural, biodegradable, and biocompatible
fibre composed mostly of keratin protein, the same physical structure as collagen
(protein) and largely forms the outer layer of human skin. Currently in New
Zealand, coarse wool fibre produced from sheep is largely considered for carpet
and fabrics. Some coarse wool is difficult to process into textiles as its fibre
diameter is too large and fibre length is too short for the use in carpet or textile
(garment) production and so is considered a waste product. These detrimental
issues create an opportunity for this study to be conducted. Fundamentally, this
study outlines a novel method to improve hydrophilic properties of
hydroentangled wool fibre fabrics. This was achieved by combining chemical
exposure and microwave (MW) irradiation techniques to produce a super
hydrophilic biomaterial for the intended end-use as the middle absorbent layer of
a composite wound dressing. A process of elimination was used to determine the
most effective chemical solution concentration for best results. Wool fabric
specimens were treated with a range of different concentrations of potassium
hydroxide (KOH) only and potassium hydroxide/hydrogen peroxide (KOH/H202)
treatments for different time periods. Characterisation of these specimens
showed 2% KOH/2% H202 treatments were best. Further optimisation was
conducted by adjusting irradiation settings of MW to find the optimum
treatment. Optimised wool fabric characterisation testing protocols included
Fourier-transform infrared spectroscopy (FTIR), water droplet contact angle,
dye droplet surface area absorption test, a visual examination of wool fibre
surface via scanning electron microscopy (SEM), water absorption capacity, and
keratinocyte cell biocompatibility tests (viability and proliferation). The
characterisation tests of all 2% KOH/2% H2O2 + MW irradiation treatments were
promising and can be considered successful to some degree. However, 2%
KOH/2% H2O2 + MW irradiation for 2 minutes at 40oC was considered the most
effective treatment for producing a super hydrophilic hydroentangled wool
material
Dose-response relationship between stair climbing duration and cognitive performance and mood in healthy young adults: A randomised cross-over controlled trial
No full textPrevious research indicates that even a single bout of exercise can improve cognitive performance and mood, but this has largely been demonstrated using specialised exercise equipment. Thus, there is need for an intervention that is easily translatable into everyday life. Considering this, the current study used stair climbing as a form of exercise intervention that is easily accessible and has high ecological validity. Building on recent evidence that stair climbing has positive effects on cognitive performance and mood, in the current study we sought to investigate a potential dose-response relationship between stair climbing duration and cognitive performance and mood, using a controlled randomised cross-over design. Thirty-six participants (mean age = 19.72 ± 2.20 years) attended three sessions: control, 3 stair climb and 6 stair climb. The stair climb sessions differed in the duration of exercise. During the 3 stair climb session participants completed 3 × 1 min stair climbing whereas for the 6 stair climb session participants completed 6 × 1 min stair climbing, with 45 s rest (walking) in between the intervals during both sessions. Participants completed cognitive tests (Pro, Anti, Pro/Anti) and visual analogue mood scales during each session, either after exercise during the stair climb sessions, or without exercise during the control session. Regarding cognitive performance, consistent with our hypothesis, we found a main effect of session, with the pattern of overall cognitive performance consistent with a dose- response relationship. Additionally, performance on the Pro/Anti task showed a dose- response pattern, with tendencies for better performance during the 6 stair climb session compared to 3 stair climb session. Mood benefits were limited and for the most part did not show dose-response relationships, although participants reported feeling more energetic post the 6 × 1 stair climbing protocol. Overall, the findings suggest that 6 stair climbing intervals is more beneficial than 3 stair climbing intervals, and stair climbing can be used as an effective intervention to improve cognition and mood
NZDep2018 analysis of census 2018 variables - TA015: Matamata-Piako 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/
NZDep2018 analysis of census 2018 variables - TA018: Otorohanga 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/