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Aeolian Sedimentation on Equatorial Reef Islands
No full textAeolian landforms have been recorded on reef islands between 7° - 25° S, but never in equatorial settings. While evidence of aeolian activity has been observed, the significance of aeolian sedimentation has not been considered in the current model of reef island development. Reef islands are derived from biogenic sediments produced on the reef platform. Sea level rise and an increase in ocean acidification and extreme weather events are expected as a response to anthropogenically forced climate change. The response of reef islands to these processes is currently unknown. It is suggested that aeolian sedimentation provides a key mechanism of reef island accretion above the limit of marine processes. This research will investigate the significance of aeolian sedimentation of low-lying islands in an equatorial setting.
This study presents high-frequency measurements of aeolian sedimentation and incident and near surface wind flow on a lagoon sand cay (Maaodegalaa) in the Maldives. Wind flow was recorded using sonic anemometers operating at 1 Hz over 8 days during the Iruvai monsoon in January and February 2018. WenglorTM particles counters, also operated at 1 Hz, and self-orientating swinging sediment traps, were used to measure sedimentation and particle flux at the bed during two high speed wind events, on the 31st of January and the 1st of February 2018. Island topography and vegetation cover were surveyed using RPAS (Remote Piloted Aircraft System) photogrammetry and a laser level. Sand samples were collected from the surface and through a series of pits on two landforms in Huvadhoo Atoll. Particle distribution analysis was completed at the University of Melbourne using a Beckman Coulter LS 13 320 laser diffractor.
Four distinct transitional stages of island form were identified in Huvadhoo lagoon; ; (i) patch reefs with submarine sediment deposits; (ii) ephemeral sediment deposits which are covered at spring high tide; (iii) sand cays which rise above spring high tides and are colonised by early successional vegetation species; and (iv) forested islands with stable cores. Each island form is progressively more stable which is associated with increasing vegetation cover. Beach rock is also associated with island stability, but only one occurrence was reported in the lagoon.
The subaerial surface of Maaodegalaa is comprised of medium-size coral sands. As no tsunami or over-wash events were reported since the formation of the island in its current position since 2011, these sands are likely deposited through aeolian processes. Coarse and fine layers within the stratigraphy became gradually finer closer to the surface, but an unequivocal aeolian facies could not be determined from grain size characteristics alone.
Significant sediment flux was recorded on Maaodegalaa during the Iruvai monsoon (35,848.13 g/hour/m2). This was recorded in the lee of a scarp during the second recorded high-speed wind event. Higher rates of sedimentation occurred in the lee of a scarp, which indicates that flow acceleration over scarps is likely to provide higher rates of sand flux compared with flow over simple topographies. Aeolian accretion may be a significant phase in reef island development. The length of this period will differ between island morphology, seasonal forms, vegetation cover and exposure to incident wind. Ultimately it will be limited by vegetation cover, which decreases the potential for aeolian sedimentation through and increase in surface roughness and shelter.
This research proposes a model where island accretion results from a combination of aeolian sedimentation and plant colonisation. The initial ephemeral surface provides an environment conducive to seed germination. The increase in surface roughness from vegetation colonisation also promotes accretion through growth of aeolian landforms. This model is independent of sea-level over decadal time scales. The period over which aeolian accretion and plant colonisation occur simultaneously is unknown, but it is likely to occur over years to decades.
This research is the first to record aeolian sedimentation in an equatorial setting. It is also the first to consider aeolian accretion in a model of reef island development. However, a clear aeolian facies could not be identified using only Folk and Ward grain size statistics, and it is recommended that sediment shape and composition is analysed in further research
The Efficacy and Mechanism of Action of HDAC Inhibitors in Triple Negative Breast Cancer
No full textHistone deacetylase inhibitors (HDACis) are a class of chemically heterogeneous anticancer agents which consist of a hydrophobic capping group, linker region, and Zn 2+ chelating pharmacophore. Manipulation of these three regions, such as the incorporation of a pyridine capping group, and hydroxythiopyridone Zn 2+ binding group has yielded Jazz-90, and M1S and M2S, respectively. Alongside vorinostat, these HDACis were tested for their cytotoxicity and activity in triple negative MDA-MB-231 and MDA-MB-468 breast cancer cells. The novel compound Jazz-90 displayed the greatest cytotoxic potency in MDA-MB-231 cells (EC 50 1.14 μM) while M1S had an EC 50 of 1.66 μM in MDA-MB-468 cells. Time-course cytotoxicity studies showed the compounds to have a cytostatic effect at the EC 50 concentration (1X) and a cytotoxic effect at four-fold the EC 50 concentration (4X). Furthermore, the effect on protein expression was determined using Western blotting at 24 h post-treatment. Relative to their cytotoxicity, the EC 50 of vorinostat (2.10 μM) showed the greatest increase in acetylated histone-H3 protein expression followed by 1X Jazz-90, 1472% and 1041%, respectively, compared to control in MDA-MB-231 cells; a similar trend was seen in MDA- MB-468 cells. Compared to vehicle control, only 4X of M1S (6.66 μM) and M2S (17.17 μM) significantly increased acetylated histone-H3 expression in MDA-MB-468 cells, 11404% and 10795%, respectively. Cell cycle protein analysis revealed that compared to control 1X of vorinostat, M1S, and M2S significantly downregulated cyclin B1 expression in MDA-MB-231 cells by 56%, 65%, and 29%, respectively, suggesting the compounds to induce G 2 /M-phase arrest. Interestingly, 1X of M1S and M2S were found to significantly increase cyclin D1 expression in MDA-MB-231 cells by 122% and 97%, respectively, suggesting that the compounds promote progression through the G 1 -phase. No change in total cyclin E2, Hsp90, or NF-κB p65 protein expression was seen in either cell line, p53 in MDA-MB-231 cells, or nuclear Hsp90 and nuclear NF-κB p65 in MDA-MB-468 cells. Thus, our findings provide evidence of the cytotoxic potency of Jazz-90, M1S, and M2S, but limited HDAC inhibitory effects in TNBC cells in vitro, hence warranting further modulation of the capping and Zn 2+ binding moieties to enhance their HDAC inhibitory profile
Gonad enhancement of Evechinus chloroticus (Val.) in Otago Harbour, New Zealand, using artificial and macro-algae diets
No full textThe endemic New Zealand echinoid, Evechinus chloroticus (Valenciennes), was collected bi-monthly between May 1999 and June 2000 from Elizabeth Island, Doubtful Sound, and held in shallow water sea cages in Otago Harbour, Dunedin, New Zealand. Three experiments (Sept-Nov 1999, Dec 1999-Feb 2000, Mar-May 2000) tested a range of algal diets (Macrocystis pyrifera, Gracilaria chilensis, and
Ulva lactuca) against an extruded artificial feed during the annual reproductive cycle of E. chloroticus (spring-autumn). Diet switching, cumulative gonad growth and density factors, in addition to gonad and gut indices, gametogenesis and roe colour, were investigated.
Evechinus chloroticus at Elizabeth Island commenced gametogenesis in late winter/spring (July-August 1999) and spawned in early summer (NovemberDecember 1999) with a gonad index of 20.25% and 8.30% respectively. The artificial diet recorded the largest growth in gonad indices (23.15%, 18.83% and 20.81 %) in all three experiments, significantly higher (ANOVA post-hoc LSD; p=0.034) than all other diet treatments and field samples. Of the algal diets, Macrocystis pyrtfera recorded the largest growth in gonad indices (18.16%, 12.96%, and 18.29%), significantly higher (ANOVA post-hoc LSD; p=0.049) than all other algal treatments and end field samples. The G. chilensis and U. lactuca diets produced negligible gonad growth in Experiment 1 and 2. The brightest roe colours were produced on the M. pyrifera and artificial/M. pyrifera diet switch treatments in Experiment 3 during the 'recovery' stage of gametogenesis in Elizabeth Island sea urchins. Low mortality (0.43%; Experiment 3), feeding rates (1gurchin/day artificial diet) and experimental length (9 weeks) suggest the use of sea cages for experimental E. chloroticus gonad enhancement has been realised in this study
Knowing (from) me, knowing (from) you: Essays on memory and testimony
No full textThis thesis is a collection of four related but self-standing chapters about memory and testimony. In Chapter 1, I argue that memory and testimony are analogous because both are reconstructive, incorporating information from sources in relevantly similar ways. In Chapter 2, I begin with the standard taxonomy of memory, according to which memory-how (procedural memory) is distinct from memory-that (episodic or semantic memory). From there, I develop an account of testimony-how by arguing that testimony need not be propositional. In Chapter 3, I turn to the curious case of the Mandela Effect and argue that it is an instance of collective confabulation, in which large groups of people develop highly similar apparent memories of events that never occurred. For at least some of these cases, I claim, testimony is an integral ingredient in the production of collective confabulations. In Chapter 4, I proceed from the analogy between testimony and memory and argue that testimonial injustice has a memorial analogue, which I call memorial injustice. I consider internalised false confessions to be an example of memorial injustice, and I identify failures of metacognition as being a key component the precipitation thereof. Ultimately, the work in this thesis leads me to the conclusion that while social epistemologists have focussed on the social factors influencing the epistemology of testimony, the ways that social phenomena influence memory and remembering are too great to ignore. I do not offer a positive account of how social epistemology ought to treat memory, but I hope that thinking about the relationship and similarities between memory and testimony offers a new perspective from which to view both
The Paragenesis of the Orogenic Gold Deposits of Te Oneroa Bay, Preservation Inlet, Southwest Fiordland
No full textThe Te Oneroa Bay area in Preservation Inlet, southwest Fiordland, has been a well-known source of hard rock and alluvial gold since the late 1800’s. Such Au-deposits are found within the Buller Terrane mid-Ordovician Preservation Formation, composed of mid-greenschist facies meta-turbidites deformed into hundred-metre scale waveforms. Large faults and shear zones cut the Preservation Formation on approximate NNW-SSE strikes along the limbs of the large waveforms. Higher permeability in the shears/faults enabled the concentration of hydrothermal fluid flow subsequently causing the precipitation of mineralised quartz vein controlled dominantly by the sericitisation and chloritisation of the host rock, decreasing pressure-temperature, and boiling of the fluid. Mineralisation is thought to have occurred via a two-step model, whereby an early stage of pyrite and arsenopyrite, and lesser galena and chalcopyrite, were introduced along with shear zone quartz pods. A secondary stage of mineralisation later occurred closely associated with ductile deformation-controlled quartz vein recrystallisation, the remobilisation of the already formed sulphide minerals, and the introduction of native gold, tetrahedrite, sphalerite, bournonite, and boulangerite along stylolites. Mineralisation likely occurred just below the brittle-ductile transition at between 1-3.5 kbar of pressure and 180-350 °C, from a fluid with near-neutral pH, low-moderate volatile content, and low salinity. A main structurally controlled branch of mineralisation is inferred to exist approximately between the historic Morning Star and Alpha Mines, as well as a smaller side branch at Golden Site Mine. Gold ranges from ~1-20 wt% silver and is thought to be hypogene; no evidence for supergene concentration exists. Due to the similarities of general geology, metamorphic grade, structure, and mineralisation of the Te Oneroa Bay area to other Buller Terrane Au-deposits, mineralisation is thought to be orogenic in origin. Fluids were predominantly produced via the dehydration of chlorite during metamorphism at ~375-330 Ma. Subsequently, Au-mineralisation is likened to have occurred at a similar time period
The analysis of intra task fluctuation of Goal Conflict Specific Rhythmicity
No full textGoal Conflict Specific Rhythmicity (GCSR) is a biomarker of an anxiety process based on Gray’s neuropsychological theory of anxiety. It provides an objective definition of anxiety, empirical measure for diagnosis, and aims to align classification with cause. GCSR discriminates patients from non-patients at a group level but not at the individual level that is required for clinical use. This thesis aims to improve the individual discriminability of the biomarker. GCSR is measured via electroencephalography (EEG) in the stop signal task (SST). (Shadli, Glue, McIntosh, & McNaughton, 2015) showed that GCSR is not consistent across the SST. GCSR fluctuation rate (GCSR-FR) is a measure of GCSR variation across the task. GCSR-FR may be a better summary of GCSR than the current method. In this study there were four groups based on patient status and a theoretically driven manipulation effectiveness (ME) factor. The non-patient effective manipulation group (NP-EM) has 49 members, non-patient ineffective manipulation group (NP-IM) has 30, patient effective manipulation group (PEM) has 38, and the patient ineffective manipulation group (P-IM) has 19. GCSR-FR was extracted from the SST in three GCSR frequency bands, 4 – 6 Hz (theta), 7 – 9 Hz (low alpha), and 10 - 12 Hz (high alpha). The domain of GCSR-FR is 1 cycle per task to 16 cycles per task. The primary analysis revealed that patient factor differences in GCSR-FR in effective manipulation relative to patient factor differences in GCSR-FR in ineffective manipulation show a quartic (m or w shaped) pattern across the GCSR-FR domain in the theta and high alpha bands. The patient factor group differences in GCSR-FR that occur in effective manipulation groups but not in ineffective manipulation groups are good targets for refining patient status prediction and therein improving GCSR’s individual discriminability. We speculate that the quartic pattern occurs because of five unique trial strategies each preferentially aggregating in one of the four groups. The finding demonstrates that there is intra task variation in GCSR that traditional summaries are incapable of detecting. With further research, GCSR-FR can improve patient status prediction
Regulation of Ark2C ubiquitylation activity
No full textUbiquitylation is a post-translational modification that regulates almost all signalling pathways in mammalian cells and its disruption is associated with a range of diseases. Ubiquitylation results in attachment of a small globular protein, ubiquitin (Ub), to substrates. It is catalysed by a cascade of enzymes called E1, E2, and E3. Specificity is mediated at two levels. The E2 conjugating enzymes determine the function of Ub signal by building polyUb chains of different linkage, whereas the E3 ligases specify the substrate and enable its modification by ubiquitin.
Among E3s, homologues Arkadia and Ark2C, a RING subclass of E3 ligases, regulate substrates in multiple pathways, including TGF-β and BMP signalling. The ability of the Ark family to partner up with several E2s, including UbcH5b and Ubc13, enables generation of distinct polyubiquitin chains that have degradative and non-degradative functions. The E3 ligase activity of Arkadia and Ark2C is regulated by the recruitment of a secondary, regulatory Ub (UbR). This Ub molecule stabilises the donor ubiquitin (UbD) of the E2∼Ub conjugate for catalysis and enables substrate modification. Although this feature has been reported, the molecular mechanism that drives the stabilisation of UbD remained unclear. This thesis presents a crystal structure of an activated UbR-Ark2C:UbcH5b∼UbD complex, which revealed crucial UbR:UbD contacts, that help to explain how the UbD is activated by Ark2C. Biochemical validation of the UbR:UbD interface identified residues, that are important for Ub transfer.
To better understand how Ark2C selects between its E2 partners, UbcH5b and Ubc13, the structure of the Ark2C:Ubc13∼Ub:Mms2 complex was solved. This enabled a comparison of Ark2C:UbcH5b and Ark2C:Ubc13 interfaces, which revealed a high level of conservation in residues that are involved.
This work characterised two key features that appear to regulate the ubiquitylation activity and confer E2 specificity. A disordered β3-RING loop, adjacent to the Ark-RING domain was analysed. This motif is rich in charged amino acids and split into the basic and acidic region. These appear to have a distinct function. Activity and binding experiments suggest, that the basic residues of the β3-RING loop enhance UbR binding, whereas the acidic residues regulate the activity of UbcH5b. Additionally, an N-terminal extension, predicted to form a helical motif was examined. This extension, termed the YEELL motif, is conserved among four human RING E3s, and regulates activity of UbcH5b, but not Ubc13. The importance of the YEELL motif for substrate modification was also established.
These finding suggest, that RING E3 ligases might form complexes with multiple E2s through a conserved set of residues, however the E2-specific regulation might be maintained by features that are found outside the RING domain
Markan typology: Miracle, scripture and Christology in Mark 4:35-6:45
No full textIn this thesis I will argue for the presence of typological use of scripture in the composition of four adjacent miracle accounts in Mark’s Gospel (4:35-41; 5:1-20; 5:21-43; 6:30-45). I will argue that these miracle accounts make deliberate and sustained use of literary narrative allusion to corresponding miracle accounts from the Jewish scriptures. While some of these allusions have been suggested before, this study argues for hitherto unnoticed allusions, as well as a consistent compositional approach within Mark’s Gospel over several miracles. These miracle accounts contain verbal, narrative and thematic correspondences that, I will argue, are best explained by the presence of a scriptural typology. This compositional approach, which is here called literary typology, also reveals underlying theological and Christological convictions. These convictions situate Mark’s Jesus firstly as the denouement of salvation history through, what I will call, fulfilment typology; and secondly identify him to an unprecedented extent with the God of Israel, which is expressed by, what I will call, theomorphic typology.
Following an introductory chapter, it will be argued that elements of this typological approach are evident in several early Jewish texts prior to or contemporaneous with Mark, in order to demonstrate the historical plausibility of Mark employing such an approach. Then, four exegetical chapters will argue for these literary, fulfilment and theomorphic typologies in the four miracle accounts considered. These will suggest extended typological allusions to the scriptural narratives of Jonah, David, Elisha and Moses. They will also discuss the hermeneutical significance of recognising each miracle’s implicit typology. Then, a chapter will argue that this typological approach to scripture use is congruent with scripture use in other significant episodes of Mark’s Gospel, even if it does not follow exactly the same pattern. Finally, the results of this study will be considered within the contemporary “early high Christology” debate, focussing especially on the work of Richard Bauckham and Daniel Kirk. The applicability of their respective early Jewish paradigms of “divine identity” and “exalted human figures” to the Gospel of Mark will be evaluated. The study will conclude that the presentation of Jesus in Mark’s Gospel is best understood according to its own categories and not according to those distilled from the diverse corpus of extant early Jewish writings. Thus, this thesis seeks to make an original contribution to the scholarly understanding of miracles, use of scripture, and Christology in the Gospel of Mark
Time to surgery for fractured neck of femur in the Waikato District Health Board. Comparison between rural and metropolitan hospitals 2017-2019
No full textPeer Reviewe
The impact of nineteenth century science and biblical criticism on expressions of faith and theology, with especial reference to the Anglican, Methodist and Presbyterial Churches of New Zealand
No full textThis thesis deals with aspects of the history of the faithscience interaction in New Zealand in relation to the Anglican, Methodist and Presbyterian Churches, during the Victorian era.
1. Chapter one gives a general introduction to four factors received from the British scientific tradition that were to play a significant part in the early discussions about science and faith
during the missionary and early colonial period. These are: (a) the Baconian ideal of science; (b) the status of Newton and Newtonianism; (c) the development of geology and biology and their relationship to natural theology; (d) the initial reception of Darwin's The Origin of Species.
2. Chapters two and three focus upon the contributions of the missionaries and early settlers to the faith-science interaction, with particular emphasis on W. Colenso and R. Taylor, the leading missionary scientists of the period. Note is taken of the underlying tension generated between reconciling the new findings of geology and the Biblical account of creation. Chapter three explores aspects of the emerging social context for science and faith during the early settler period, especially concentrating on the class settlements of Dunedin and Christchurch, both of which had strong religious affiliations. Samuel Butler's notable work in drawing attention to Darwin's The Origin of Species is highlighted.
3. Chapter four details the way in which the new theories of Biblical criticism, coming to prominence coterminously with Darwin's theories, combined to cause various controversies over what constituted Biblical truth, scientific truth, and called into question the status of both revealed religion and natural theology. Theological reaction to the ascendency of science, sometimes characterised by a retreat into Biblical literalism and the appeal to miracle, is analyzed. The range
of clerical opinion about science is revealed in the writings of various church leaders, notably A.R. Fitchett, S.T. Nevill, R. Waddell, and W. Salmond.
4. In chapter five the formation, life and some of the personalities of the New Zealand Institute are discussed with particular reference to three major debates: the status of natural theology, the status of speculative geometry, and the status of the book of Genesis in relation to scientific knowledge. The popularity of astronomy, with its influence on the symbolic language of faith, is also considered. A contrast is drawn between declining clerical interest in science and mathematics, and the concept of the mathematization of nature as an objective of modern science