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Conspiracy theory beliefs: measurement and the role of perceived lack of control
No full textDespite conspiracy theory beliefs’ potential to lead to negative outcomes, psychologists have only relatively recently taken a strong interest in their measurement and underlying mechanisms. In this thesis I test a particularly common motivational claim about the origin of conspiracy theory beliefs: that they are driven by threats to personal control. Arguing that previous experimental studies have used inconsistent and potentially confounded measures of conspiracy beliefs, I first developed and validated a new Conspiracy Mentality Scale, and then used it to test the control hypothesis in six systematic and well-powered studies. Little evidence for the hypothesis was found in these studies, or in a subsequent meta-analysis of all experimental evidence on the subject, although the latter indicated that specific measures of conspiracies are more likely to change in response to control manipulations than are generic or abstract measures. Finally, I examine how perceived lack of control relates to conspiracy beliefs in two very different naturalistic settings, both of which are likely to threaten individuals feelings of control: a political crisis over Macedonia’s name change, and series of tornadoes in North America. In the first, I found that participants who had opposed the name change reported stronger conspiracy beliefs than those who has supported it. In the second, participants who had been more seriously affected by the tornadoes reported decreased control, which in turn predicted their conspiracy beliefs, but only for threat-related claims. Tentatively, I conclude that threats to control can motivate conspiracy ideation, but only under particular conditions, such as when the threat is extreme and a conspiracy theory is available that offers a relevant explanation, although further research is necessary to explore the boundaries of the effects
Annotation and evolution of bacterial ncRNA genes
No full textSuccessful pathogenic bacteria must alter gene expression in response to changing and hostile environments. Non-coding RNAs (ncRNAs) contribute to adaptability and pathogenicity by forming complex regulatory networks, and include riboswitches, cis-regulatory elements and sRNAs. Despite their important biological function, the annotation and discovery of ncRNAs is hindered by a lack of sequence conservation or other distinguishing sequence features.
Studies of the evolutionary dynamics and origins of sRNA genes have been hindered by poor sequence conservation, which makes annotation via sequence homology challenging. The short length and relative simplicity of sRNA genes also make them interesting candidates for observing de novo gene formation from transcriptional noise, or exaptation from existing elements.
We have used a pipeline based on profile hidden Markov models to study the conservation patterns of sRNA genes from Salmonella Typhimurium. Our results show that sRNAs are both rapidly acquired and exhibit rapid sequence turnover. We found that horizontal gene transfer is the main driver of sRNA acquisition in Salmonella, and identified Salmonella-specific sRNAs that appear to be derived from phage control systems, and other mobile genetic elements, as well as Type I toxin-antitoxin systems. This method was then applied to study ncRNAs in Pseudomonas syringae pv. actinidiae (Psa), the causal agent of kiwifruit canker disease. We have generated transcriptomes of a pandemic strain of Psa in multiple growth conditions in vitro, and analysed gene expression changes and identified novel non-coding transcripts. We then studied the expression and conservation of these candidate ncRNAs, and identified several with predicted secondary structure motifs characteristic to known functional ncRNAs.
This thesis also includes a summary of two genome assembly projects of Gemmata and Legionella isolates, as part of larger collaborations. All diagrams in this thesis are my own work, unless otherwise state
In situ expression of biomarkers in placenta in the context of hypertensive disorders of pregnancy
No full textOverview: Hypertensive disorders in pregnancy (HDP), of which the most common is pre- eclampsia (PE), are a leading cause of maternal and foetal morbidity and mortality worldwide. Despite extensive research, no clear cause or mechanism for HDP has been discovered. Human papillomavirus (HPV) has transformative abilities among many cell types and alters key pathways in reproductive cells essential for embryo implantation and placental development in vitro. It has also been consistently found in the placentae, especially in those complicated by PE. These findings suggest HPV may not be only a bystander in complicated pregnancies, but has a direct role in abnormal placental development. Whether HPV genes such as E6/E7 that encode the E6 and E7 proteins, which affect trophoblast function in vitro, are expressed in vivo is unknown. Understanding gene expression profiles in placental tissue is complicated by the wide variety of cell types present and their distinct genetic origins. This study used RNAscope® to investigate whether in situ based techniques could identify HPV E6/E7 expression differences in placentas from a cohort of Japanese women. A second aspect of this study used RNAscope® to investigate if genes found to be differentially methylated in the cohort were associated with HDP. NOTCH2 and CMIP were chosen.
Methods: Fifteen placenta from uncomplicated pregnancies, sixteen placenta from pregnancies complicated by HDP, and six additional cases of non-HDP pathologies, were converted to FFPE slides and examined using RNAScope®, or immunohistochemistry. RNAscope® assays to determine RNA quality, non-specific staining, HPV high-risk E6/E7, HPV low-risk E6/E7 and NOTCH2 were undertaken, along with immunohistochemistry for CMIP. Results were compared between the HDP and control groups.
Results: The majority of placentas from the HDP (n=15/16, 94%) and the control (n=11/15, 73%) cohorts had sufficient RNA quality. In the HDP group, six cases (n=6/15) tested positive for high risk HPV E6/E7 (40%), and five tested positive for low risk HPV E6/E7 (33%). None of the control cases tested positive for high risk HPV (0%) or low risk HPV (0%). Expression of HPV high and low risk E6/E7 was increased in the HDP compared to the control cohort (p<0.05). The NOTCH2 assay was optimised and NOTCH2 was expressed heterogeneously between neighbouring cells in individual cases, but the number of cases tested was too low for statistical power. The CMIP assay did not work, requiring further optimisation.
Conclusion: This study provides evidence that HPV high and low risk E6/E7 is expressed in the placenta of pregnancies complicated by HDP. These results add validity that HPV may affect placental function by showing HPV gene expression is active in the HDP affected placenta. Further research is needed to understand why transcriptionally active HPV E6/E7, of both high and low risk types, would be present in the developing and term placenta. In addition, RNAscope® proved viable for visualising cell types to target for further sequencing, which could be used to determine if one cell population is more differentially methylated within the heterogeneous placenta
Matthew 27:26-31 Contextual Bible Study card
No full textThe paper "A Contextual Bible Study on the Crucifixion of Jesus: Engaging the issue of male violence against men" is available at http://hdl.handle.net/10523/10236This double-sided A4 contextual bible study card was created in 2020 to accompany 'A Contextual Bible Study on the Crucifixion of Jesus: Engaging the issue of male violence against men', which was developed in 2019 by the Ujamaa Centre, University of KwaZulu-Natal, and the Centre for Theology and Public Issues, University of Otago. One side of the card features the text for Matthew 27:26-31 on the striping of Jesus with the text presented in IsiZulu, Sesotho, and English. The other side of the card features the image 'Jesus is Stripped of His Garments', The Tenth Station of the Cross, Church of the Holy Cross, Sisak, Croatia (image attribution Zatletic)
Abundance estimation of Hector's dolphin
No full textThis thesis reports the results of the first boat-based line-transect survey to be carried out in New Zealand waters. The survey was carried out in January and February 1998, successfully adapting conventional line-transect methods for use on a privately owned 15m catamaran, R. V. Catalyst. The survey proved that line-transect methods could work well on much smaller cheaper vessels than those generally used on surveys overseas. Analysis of dolphin orientation data suggested, however, that abundance estimates were positively biased as a result of dolphins swimming towards the survey vessel. Further, a comparison of the Akaroa Harbour abundance estimate (124, 95% c.i. 85-181) with previous survey work indicated that estimates may have been biased high. The results from just 3 of 115 small boat surveys of Ak:aroa Harbour fall within the uncorrected 95% confidence limits, and the average summer abundance seen on these surveys was 43 animals (95% c.i. 34-52).
During the following field season (November 1998 to February 1999), combined boat and helicopter surveys were carried out in the waters off Banks Peninsula. A correction factor was derived that accounted both for vessel attraction and for dolphins missed on the trackline. The corrected Hector's dolphin abundance estimate from Motunau- Timaru (0-4 nautical miles offshore) is 1198 (95% c.i. 709-2025). Survey coverage was extended during this season from Timaru to Long Point, west of Te Waewae Bay in Foveaux Strait. The corrected abundance estimate for this area (0 - 4 n.mi. offshore) is 399 (232-686). A total inshore abundance estimate of Hector's dolphins from Motunau to Long Point is 1596 (1002-2546).
A further objective was to determine the effect of survey design on abundance estimates, as a step towards developing guidelines for the design of inshore linetransect surveys. Data collected during the 1998 survey were used to develop a hypothetical dolphin population, which was sampled via computer simulations to determine the relative efficiencies of different survey designs. Results indicated that systematic surveys will generally be more precise than those with random line selection, and that the effect of stratification on abundance estimates and precision is negligible. These results provide some guidance for the design of future inshore surveys. Further, the simulation methods developed here could be modified to investigate the viability of adaptive line-transect sampling
Sleep in Pasifika Adolescents
No full textSleep of adequate duration and quality is crucial for maintaining physical and mental health. Recent research, however, suggests that Pasifika youth in New Zealand (NZ) may not be getting enough good quality sleep. This, in turn, may be contributing to health disparities between Pasifika and the other NZ population groups. This study aimed to describe perceptions of Pasifika adolescents about sleep, their thoughts on how Pasifika culture impacts on sleep, and the appropriateness of potential interventions to improve sleep within Pasifika families.
This study involved qualitative interviews with local Pasifika high school students, underpinned by the Talanoa research method and the University of Otago Pacific Research Protocols. Transcripts from these interviews were analysed using thematic analysis, noting common themes that arose from the interviews.
The results suggest that most Pasifika adolescents felt they had challenges in getting enough sleep. Alongside challenges that are consistent with adolescents worldwide (e.g. a delayed circadian rhythm and a tendency to catch up on missed sleep in the weekends), they felt some were more specifically related to aspects of Pasifika family values and lived experiences. For example, many mentioned living with large families that had inconsistent sleep patterns, attending family, cultural, and church/community events or activities during some evenings, and feeling high extracurricular and academic pressures, all which they felt negatively affected their sleep.
In discussions about acceptability of different sleep interventions, participants indicated that the interventions likely to have the biggest positive impact would include sleep education for adolescents and their families, parental-set bedtimes, and restricting screen technology use.
In conclusion, Pasifika adolescents noted several challenges to their sleep, some likely to be specific to Pasifika family contexts. This context also featured in solutions to these challenges, with the most popular interventions empowering families to work together to support sleep and wellbeing
Adolescent autonomy in medical decision making
No full textNormally in the health profession there is a requirement to gain valid consent from patients before treatment can be given. This respect for patient autonomy has become a cornerstone of modern medical practice, however not all people are considered to be autonomous. Below a certain age, people are assumed not to be autonomous and can only consent to and refuse treatment if they can prove themselves competent. Currently there is no clear guidance for clinicians about to how to deal with patients under the legal age of medical consent who wish to choose treatment for themselves. This thesis seeks to explore the idea of adolescent consent and the problems associated with it. By considering a number of philosophical, neurological and developmental sources, as well as cases and specific laws, I intend to consider an approach to adolescent autonomy which could fill some of the conceptual gaps which there are in the current medical approach. In the following thesis I will discuss the importance of well-being, autonomy and liberty to the medical profession. I will discuss how these three things should be weighed against each other. As part of this discussion I present a framework to consider autonomy both generally and as it relates to adolescents specifically. I also consider a variety of approaches to development to their suitability to this subject. In the conclusion of this thesis I find that respect for autonomy is important in the medical system and that this respect should be extended to adolescent's who can be shown to be autonomous
The Role of Lhx9 in the Male Reproductive System
No full textLeydig cells (LCs) are found within the interstitium of the testes. LCs are crucial to male reproductive function due to their role in testosterone synthesis, a process vital for both organogenesis and secondary sex characteristic development. The generation of LCs differs between foetal and adult testes. During embryonic development, LCs differentiate from progenitors, their numbers peaking at embryonic day 15.5 (E15.5), then degenerating at birth. Postnatally, the stem LC (SLC) population is activated at puberty, providing the precursor pool where the adult LCs (ALCs) will later differentiate from. The exact mechanisms of this process are not well understood. The LIM homeobox 9 gene, Lhx9, is essential for the formation of the gonad, it is also expressed later in development in the testes interstitium in both foetal and adult LCs. The functional role of Lhx9 associated with this expression has been poorly characterised. We hypothesise that the Lhx9 is vital for forming the progenitor population from which LCs later differentiate. The effect of Lhx9 loss on the foetal or adult LC pools has not been studied.
Gene expression was compared between Lhx9+/+ (WT) and Lhx9+/- (HET) mouse testes at two stages: E15.5 (using RT-qPCR), and adult (RNA-Sequencing). In the adult testes, 51 genes were found to be differentially expressed between the WT and HET mice. Additionally, gene ontology analysis revealed enrichment for genes involved in lipid metabolism. This pathway is utilised by LCs for testosterone production. At E15.5, expression of marker genes for progenitor stem cell populations, such as Nestin and Notch, was significantly reduced in the HET testes compared to the WT littermates. Conversely, steroidogenesis genes showed a significant increase in expression; supporting the hypothesis that Lhx9 acts to maintain the LC progenitor population in the testes.
Treatment of testes with ethane dimethanesulfonate (EDS) in vivo causes the death of Leydig cells, allowing analysis of their regenerative capability. Preliminary results of qPCR analysis following EDS treatment in adult HET and WT testes shows altered expression of a few genes, such as a decrease in Nestin in EDS treated HET mice. Together, these results will not only provide further understanding of the role of Lhx9 in foetal and adult testis, but additionally help illustrate delicate balance of progenitor populations and their impact on secondary sex determination and fertility in the adult
Effectiveness of bi-annual application of 38% silver diamine fluoride and 5% sodium fluoride varnish on primary teeth of children, in a rural setting near Port Moresby, Papua New Guinea - A randomised clinical trial
No full textAim: To assess the effectiveness of 38% silver diamine fluoride (SDF) solution and 5% sodium fluoride (NaF) varnish applied bi-annually in arresting carious lesions in primary teeth of children and to assess child and parent acceptability of the treatments.
Methods: Children aged 2-5 years with at least one carious lesion were randomly allocated into 2 groups as follows: Group 1 received 38% SDF (Riva star SDI Ltd) solution and Group 2 received 5% NaF varnish (Duraphat®), applied at baseline and again at 6 months. Lesion progress or arrest was assessed by visual and tactile examination at 6 months and 12 months. Parental and child satisfaction were assessed with self-reports at 6 months and 12 months.
Results: One hundred and four children were recruited. Baseline mean dmfs scores were 10.8 and 11.7 for Group 1 and 2 respectively. At 12 months, 86.5% (90) participants remained in the study. The caries arrest rate in SDF group, was higher than that of NaF group, 97.2% vs 71.5 % (p < 0.001). Logistic regression analysis showed that 38% SDF was more effective than the 5% NaF varnish (OR: 7.7, 95% CI=3.14 -19.09) in arresting carious lesions. There were no differences in parental and child satisfaction between the groups.
Conclusion: At 12 months, both 38% SDF and 5% NaF were effective in arresting dental carious lesions, however 38% SDF was superior to 5% NaF. Parents and children were accepting of the treatment provided
Pleiotrophin family gene and protein expression in a sheep tooth socket model of bone healing
No full textResorption of alveolar bone after tooth extraction is a common problem. Bone replacement materials are used to enhance socket healing and reduce alveolar bone loss. The success of the graft is dependent on multiple factors including the presence of growth factors. This is the first in vivo study to investigate the expression of the pleiotrophin family of cytokines in association with a grafting material during bone regeneration.
Objective: To investigate the role of the growth factor family of pleiotrophin/midkine and their receptors, during osteogenesis with and without a grafting material, after tooth extraction in a sheep model.
Methods: Thirty Romney-cross ewes were anaesthetised and all premolar teeth on the right side were extracted. The sockets were randomised to controls sites with no treatment and test sites with Bio-Oss® graft material and Bio-Gide® membrane. Samples were harvested after sacrificing animals 4, 8, and 16 weeks post-grafting (n=10 per time-point). Tissue for qRT2-PCR gene analysis was recovered from the socket next to the first molar using a trephine (Ø=2mm). Each socket was fixed, decalcified, paraffin-embedded and sectioned. Immunohistochemistry (IHC) was conducted to localise pleiotrophin and midkine and their receptors anaplastic lymphoma kinase (ALK), receptor-type tyrosine-protein phosphatase zeta (RPTPζ) and notch-2.
Results: Within the healing sockets high expression of genes for pleiotrophin, midkine, notch-2, and ALK were found at all time-points and in both grafted and non-grafted sites, while RPTPζ was only expressed at low levels. The relative gene expression of the PTN family of cytokines were not statistically different at the three time-points and between test and control groups (p>0.05). Immunohistochemistry found pleiotrophin and midkine in association with new bone, notch-2 in the connective tissue and intranuclear localisation of RPTPζ and ALK in association with cuboidal osteoblasts involved in bone formation.
Conclusions: The pleiotrophin family was expressed in both non-grafted and grafted sockets during osteogenesis in a sheep model of alveolar bone regeneration. The discovery of the pleiotrophin/midkine family as important during alveolar bone regeneration is novel and opens up new avenues of research. Growth factor supplementation with pleiotrophin and/or midkine during healing may be an approach for enhanced regeneration or to initiate healing where delayed. The activation of notch-2 and RPTPζ may be important to bone regeneration in vivo