Doctor of Philosophy

dissertationThe public school superintendency has been a professional field that has been dominated by men. Although statistics surrounding gender and the superintendency are changing, progress has been modest. This necessitated that I elicit stories from female superintendents because their experiences are literally not represented in the archives, in either school district data or education policy research. This study asks the following questions: 1. What are the personal and professional experiences of past and/or present female superintendents in Utah? 2. What key factors influenced their trajectory into the superintendency? However, what I experienced and found was much more. Throughout data collection, the participants discussed how they negotiated being in a position of power where they were unexpected to be. Further, the dissertation begins to address the complex relationships between structural, discursive, and socialization frameworks that impact how women in the superintendency experience their roles and gender roles. Findings include gender bias, balancing personal and professional lives, working with school boards, mentoring, and the encouragement of more women to pursue their dreams. Recommendations for future research include exploring health issues superintendents face, if there is a difference in the quality of life of superintendents depending on their gender, looking at graduate students experiences and their preparation for leadership, and focusing specifically on retired female superintendents

Re-thinking the 2X2 scenario method: grid or frames?

Is a well-accepted method widely used by practitioners unproblematic? We here suggest that this is not the case. The 2x2 matrix approach has been stated by researchers to be the ‘standard’ approach in scenario planning. However, as we show in this paper, interpretations of this method vary significantly, even within the same ‘scenario school’ – in this case, the intuitive logics - plausibility based scenario tradition. We explore both the highly attractive, apparent simplicity of the method; and its more problematic aspects by contrasting two distinct interpretations used by scenario planners. We articulate the advantages and drawbacks of the 2x2 matrix method according to these two different interpretations. The paper makes two contributions. First, in rendering methodological conundrums explicit, it clarifies choices scenario planners can now explicitly make when choosing a scenario building method. Secondly, by clarifying the choices that the method offers, we contribute to make it more rigorous, debunking some of the purported ease it advertises for the unwary

Persistent features of intermittent transcription

Single-cell RNA sequencing is a powerful tool for exploring gene expression heterogeneity, but the results may be obscured by technical noise inherent in the experimental procedure. Here we introduce a novel parametrisation of sc-RNA data, giving estimates of the probability of activation of a gene and its peak transcription rate, which are agnostic about the mechanism underlying the fluctuations in the counts. Applying this approach to single cell mRNA counts across different tissues of adult mice, we find that peak transcription levels are approximately constant across different tissue types, in contrast to the gene expression probabilities which are, for many genes, markedly different. Many genes are only observed in a small fraction of cells. An investigation of correlation between genes activities shows that this is primarily due to temporal intermittency of transcription, rather than some genes being expressed in specialised cell types. Both the probability of activation and the peak transcription rate have a very wide ranges of values, with a probability density function well approximated by a power law. Taken together, our results indicate that the peak rate of transcription is a persistent property of a gene, and that differences in gene expression are modulated by temporal intermittency of the transcription

The Receptor-Like Kinase SERK3/BAK1 Is Required for Basal Resistance against the Late Blight Pathogen Phytophthora infestans in Nicotiana benthamiana

BACKGROUND The filamentous oomycete plant pathogen Phytophthora infestans causes late blight, an economically important disease, on members of the nightshade family (Solanaceae), such as the crop plants potato and tomato. The related plant Nicotiana benthamiana is a model system to study plant-pathogen interactions, and the susceptibility of N. benthamiana to Phytophthora species varies from susceptible to resistant. Little is known about the extent to which plant basal immunity, mediated by membrane receptors that recognise conserved pathogen-associated molecular patterns (PAMPs), contributes to P. infestans resistance. PRINCIPAL FINDINGS We found that different species of Phytophthora have varying degrees of virulence on N. benthamiana ranging from avirulence (incompatible interaction) to moderate virulence through to full aggressiveness. The leucine-rich repeat receptor-like kinase (LRR-RLK) BAK1/SERK3 is a major modulator of PAMP-triggered immunity (PTI) in Arabidopsis thaliana and N. benthamiana. We cloned two NbSerk3 homologs, NbSerk3A and NbSerk3B, from N. benthamiana based on sequence similarity to the A. thaliana gene. N. benthamiana plants silenced for NbSerk3 showed markedly enhanced susceptibility to P. infestans infection but were not altered in resistance to Phytophthora mirabilis, a sister species of P. infestans that specializes on a different host plant. Furthermore, silencing of NbSerk3 reduced the cell death response triggered by the INF1, a secreted P. infestans protein with features of PAMPs. CONCLUSIONS/SIGNIFICANCE We demonstrated that N. benthamiana NbSERK3 significantly contributes to resistance to P. infestans and regulates the immune responses triggered by the P. infestans PAMP protein INF1. In the future, the identification of novel surface receptors that associate with NbSERK3A and/or NbSERK3B should lead to the identification of new receptors that mediate recognition of oomycete PAMPs, such as INF1.This work was supported by the Gatsby Charitable Foundation, BBSRC, Nuffield Foundation and the German Research Foundation (DFG). SS was supported by a personal research fellowship (SCHO1347/1-1). JPR is an Australian Research Council Future Fellow (FT0992129). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

Re-thinking the 2X2 scenario method: grid or frames?

Abstract Is a well-accepted method widely used by practitioners unproblematic? We here suggest that this is not the case. The 2x2 matrix approach has been stated by researchers to be the 'standard' approach in scenario planning. However, as we show in this paper, interpretations of this method vary significantly, even within the same 'scenario school' -in this case, the intuitive logics -plausibility based scenario tradition. We explore both the highly attractive, apparent simplicity of the method; and its more problematic aspects by contrasting two distinct interpretations used by scenario planners. We articulate the advantages and drawbacks of the 2x2 matrix method according to these two different interpretations. The paper makes two contributions. First, in rendering methodological conundrums explicit, it clarifies choices scenario planners can now explicitly make when choosing a scenario building method. Secondly, by clarifying the choices that the method offers, we contribute to make it more rigorous, debunking some of the purported ease it advertises for the unwary. KEY WORDS Scenario planning, 2X2 matrix; deductive scenario method Introduction and objective

A Model of Boys' Body Image in Early Adolescence

"Das Hauptziel dieser Studie galt der Identifizierung essentieller Faktoren der Körperbildentwicklung in einer nicht-klinischen Stichprobe von Jungen unter Berücksichtigung möglicher Einflüsse durch Peers, Familie und Medien. Es wurden semi-strukturierte Leitfadeninterviews mit 14 früh-adoleszenten Jungen (Altersrange von 10-12 Jahren) geführt, die zufällig aus den Teilnehmern einer größeren quantitativen Fragebogenstudie (N=167) an Grundschulen in Berlin ausgewählt wurden. Mittels thematischer Analyse konnten zwei Hauptthemen identifiziert werden: (1) sozialer Vergleich (beinhaltet die beiden Subthemen Selbst-Verbesserung und Selbst-Erhöhung) und (2) Internalisierung (beinhaltet die beiden Subthemen behaviorale und kognitive Dimensionen). An Hand der Ergebnisse wurde schließlich ein finales Modell erstellt, das die Konzeptualisierung des Körperbildes von Jungen in der frühen Adoleszenz abzubilden sucht." (Autorenreferat)"The major aim of this study was to explore and promote a deeper understanding of the essential contributing factors to body image development in a non-clinical sample of boys, including the roles played by peers, family, and media. In this study, semi-structured interviews were conducted with a sample of 14 adolescent boys (ranging in age from 10-12 years) who were randomly selected from the participant pool of a larger quantitative study (N=167) conducted in elementary schools in Berlin, Germany. By using thematic analyses, two major themes were identified: (1) social comparison (including two subthemes: self-improvement and self-enhancement), and (2) internalization (including two subthemes: behavioral and cognitive dimensions). On the basis of these results, a final model of how boys conceptualize body image in early adolescence was elucidated, and can be found in the study." (author's abrstact

Relationship between spatially restricted Krox-20 gene expression in branchial neural crest and segmentation in the chick embryo hindbrain

Previous studies have suggested that the rostrocaudal patterning of branchial arches in the vertebrate embryo derives from a coordinate segmental specification of gene expression in rhombomeres (r) and neural crest. However, expression of the Krox-20 gene is restricted to neural crest cells migrating to the third branchial arch, apparently from r5, whereas this rhombomere contributes cells to both the second and third arches. We examined in the chick embryo how this spatially restricted expression is established. Expression occurs in precursors in both r5 and r6, and we show by cell labelling that both rhombomeres contribute to Krox-20-expressing neural crest, emigration occurring first from r6 and later caudally from r5. Krox-20 transcripts are not detected in some precursors in rostral r5, presaging the lack of expression in cells migrating rostrally from this rhombomere. After transposition of r6 to the position of r4 or r5, many Krox-20-expressing cells migrate rostral to the otic vesicle, whereas when r5 is transplanted to the position of r4, only a small number of migrating cells express Krox-20. These results indicate that, in the chick, Krox-20 expression in branchial neural crest does not correlate with rhombomeric segmentation, and that there may be intrinsic differences in regulation between the r5 and r6 Krox-20-expressing populations

Identifying Patients With Vesicovaginal Fistula at High Risk of Urinary Incontinence After Surgery:

To develop a risk score to identify women with vesicovaginal fistula at high risk of residual urinary incontinence after surgical repair