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Bladder cancer is 7th most common type of cancer in the UK, and presents up to 4 times more often men than in women, even when adjusting for environmental factors such as smoking and occupation. Bladder cancer also has the highest rates of mutations in chromatin modifier genes compared to any other cancer type. Despite this, studies regarding the epigenome of bladder and bladder cancer are lacking. This study considers the genome-wide transcriptional and chromatin accessibility landscape of healthy urothelium, and aims to identify gender-associated differences promoting the gender biases observed in bladder cancer. The study is the first to establish reliable protocols for chromatin immunoprecipitation (ChIP) of histone marks, and an assay for transposase-accessible chromatin followed by next generation sequencing (ATAC-seq) in normal urothelium, and the first to carry out transcriptional profiling on normal human urothelial cells (NHUC). Affymetrix HTA2.0 microarrays using three models of healthy urothelium [NHUC, immortalised NHUC (TERT-NHUC), and uncultured healthy urothelial cells (UHUC)], showed that although the majority of differentially expressed (DE) genes between genders are located on the sex chromosomes, five autosomal genes are upregulated in female NHUC that are associated with invasive bladder tumours, inflammation, and hypoxia. Furthermore, each gender showed different transcriptomic perturbations in response to common mutations in a cohort of 102 stage Ta grade 2 tumours, including in tumours with mutations in the X-linked histone demethylase KDM6A where females had DE of chromatin regulatory genes but males did not. ATAC-seq in two male and two female TERT-NHUC lines showed a genome-wide increase in chromatin accessibility in males, which could be seen by increased signal at individual loci and a greater number of overall peaks. Although this difference did not correlate with increased transcriptional activity, cell proliferation, or cell-cycle stage, it did correlate with a global increase of the activating histone marks H3K4me3 and H3K27ac, but not the heterochromatin marker H3K27me3. A reliable ChIP protocol with validated controls was developed for the histone marks H3K4me1, H3K4me3, H3K27ac, and H3K27me3, and provides a foundation for future epigenetic research in bladder cancer. The results of this study suggest that, although variation between individual donors is greater than between gender groups, future research in bladder should consider genders separately. For instance, therapeutic efforts aimed at targeting chromatin architecture, such as HDAC inhibition, may be more effective in females, particularly when they have acquired mutations in KDM6A.

The ejaculate is composed of many different parts: proteins, lipids, and much else travels alongside sperm. With so many elements comes the problem of composition. Does the mix matter for male reproductive success? To what extent is the composition fixed? What happens when males lose control over the composition? It is with these questions that this thesis is principally concerned. I start by testing whether males alter ejaculate composition in relation to the intensity of male-male competition. I find that divergent allocation rules govern the transfer of sperm and seminal fluid proteins ('SFPs'). While the allocation of both responds to competition, only SFP allocation responds to its intensity. I further show that variation between SFPs in their responsiveness leads to differentially-composed seminal fluid. The resulting ejaculate compositions are each accompanied by distinct costs and benefits for male reproductive performance, some of which appear specific to seminal fluid. I next demonstrate that loss of BMP-regulated secretions from a seminal fluid-contributing cell-type ('secondary cells') imparts a syndrome of dysregulation on male and female reproductive performance. Within this, males lose the ability to reduce female receptivity to remating, but gain an advantage in defensive sperm competition. Through a systematic dissection of different episodes influencing sperm competition outcome, I find that loss of these secretions influences sperm entry into storage and potentially enhances their resistance to displacement. In the following two chapters I show that loss of BMP-regulated secondary cell secretions and the keystone SFP sex peptide affects seminal fluid transfer to females. In both cases, I find clear signals of between-SFP dependencies in the regulation of SFP transfer, which collectively highlight novel mechanisms of seminal fluid organisation. I argue that these organising mechanisms may be used to a male's advantage to exercise fine-scale, real-time control over the transfer of ready-made seminal fluid.

Despite the vast research on the productive aspect of rewards, little is known on how the changes in employees’ behaviour, made to enhance their chances of achieving a reward, influence employee well-being. Previous work has failed to address the process of reward-seeking behaviour from an employee’s point of view as the focus was on the motivational aspect of rewards. This thesis uses the case of Malta’s financial institutions to examine the relationship between reward-seeking behaviour from bonuses and promotions and employee well-being by drawing on expectancy theory and self-determination theory. To achieve its aims, this study adopts a qualitative approach, wherein 42 semi-structured interviews with employees and four interviews with human resources managers are conducted at financial institutions in Malta – two of which are small and medium-sized enterprises and one is a large-sized institution. Memos and diary notes are also used to complement the data collected from the semi-structured interviews. Overall, the results strongly support the idea that while almost everyone values rewards, employees differ in their willingness to engage in reward-seeking behaviour and its influence on well-being. This thesis contributes to knowledge through the development of a theoretical model – the four quadrant reward-seeking behaviour – well-being model. This typology based model classifies employees into four main categories, namely, highly motivated, apathetic, work-life balanced and work-life imbalanced. This two by two matrix also led to another model that depicts reward-seeking behaviour and well-being as a non-sequential process. The findings have practical implications for human resources practitioners as they now have the capacity to visualise the actual employee mix according to the categories of the model and act on any significant gaps.