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How feedback mechanisms trigger, regulate and suppress star formation in galaxies remains one of the main questions in astronomy today. Theoretical models and cosmological simulations of galaxy formation and evolution frequently employ feedback mechanisms from active galactic nuclei (AGN) and supernovae (SNe) to quench star formation in the early stages of massive galaxy formation and to explain the low efficiency of star formation in disk galaxies. A majority of this feedback is likely due outflows, ejecting large reservoirs of star forming gas from the galaxy and quenching star formation, powered by either AGN or SNe. However, recent theoretical and numerical models suggest that feedback due to outflows may also be able to promote star formation in gas in both galactic discs and entrained within outflows themselves. This work focus upon studying the ionised component of outflows in the local Universe, with a particular focus on 'positive' feedback, where outflow feedback may trigger star formation in gas both in the galactic disk and inside the outflow itself, but also investigating the physical properties of galaxies and their negative feedback effect. To achieve this, I have developed a complex software specifically to explore multiple gaseous kinematic components in galaxies. I have applied this software to investigate outflows in the SDSS-IV MaNGA dataset, as well as data from other instruments. In the first part of this thesis I discuss the first confirmed detection of star formation within a galactic outflow. By investigating the optical and near-IR emission line ratios of the outflowing gas, I unambiguously prove star formation is occurring within the gas. This is supported by the ionisation parameter of the gas, showing the gas excitation must come from UV radiation due to stars in the outflow and not stars in the galactic disk. Finally, I trace kinematical fingerprints of young stars blueshifted relative to those in the galactic disk. The second part of this thesis focuses upon expanding the study of star formation in outflows in an unbiased sample of local galaxies. Through emission line ratios I find ∼30% of our outflow sample show signs of in-situ star formation. This is supported again by the ionisation parameter, showing the gas excitation must be due UV radiation of young stars in the outflow. Investigating the relationship between star formation rates within the outflow and ionised outflow mass rates, I find a relationship implying large amounts of star formation should occur in high-z outflows. This new channel of star formation has numerous implications for galactic evolution. The final part of this thesis focuses on general properties of ionised outflows and their effect on their host galaxies. I classify 168 outflows in local galaxies. Emission line ratios of the galactic disk show our outflow-host galaxies form a representative sample of local galaxies, v indicating outflow prevalence in all types of galaxies. I find a large fraction of the outflows are AGN-driven, though most are star formation-driven. Most star formation-driven outflows exist on or above the 'Main Sequence' in the SFR-M∗ plane, suggesting the importance of starbursts for star formation-driven outflows. AGN-driven outflows exist on and below the main sequence, suggesting their efficiency at driving outflows in all types of galaxy. By studying the gas density through the [SII] doublet, I find outflowing gas is denser than gas in the galactic disk by a factor ∼3, likely as a consequence of gas compression. Finally, by studying a number of properties of the outflowing gas, I find that some outflow properties (e.g. dynamical timescale) may be influenced by the properties of their host , whilst other properties (e.g outflow velocity) are more affected by the driving source of the outflow.

There has been an increase in the use of problem-based learning (PBL) - a student-centred approach involving authentic problem cases and collaboration - within the engineering disciplines in response to the demands of 21st century industry. The vast majority of PBL research over the years, however, has either focused on determining its effectiveness, or reported on staff and students' perceptions about the approach. Much less attention has been given to the group practices that lie at the heart of PBL. Ironically, then, as a pedagogical approach that is so dependent on social interaction, we know very little about its interactional elements - about how it actually works. With the aim of opening this interactional 'black box', this study analysed almost 100 hours of naturalistic video-recordings involving seven groups of engineering students undertaking PBL at a UK university. This thesis reports on the findings of the floating facilitator PBL model, in which learning is effectively tutorless, with only intermittent tutor contact. Conversation analysis was used to examine students' actual social interactions in this learning setting; to finely unpack the conversational mechanics behind PBL that have long been overlooked. Although the student-centredness of PBL made the educational experience less formal in nature, this democratisation of institutional structures also allowed 'outside' social norms to percolate through. Added to the absence of the tutor, PBL thus made matters more complicated for students, forcing them to balance wider social values with their newfound institutional responsibilities (i.e. to self-manage their group work). Ironically, the groups co constructed themselves as being largely detached from academia; as 'playing it cool' in blending in as ('non-academic') equals. At the same time, however, with no guiding tutor, the students also oriented to their collective need to 'do education'. In managing this dilemma - and in an apparent resistance against being substituted for the absent tutor - they treated the workload as a collective burden to be eradicated, neutralised all displays of authority, and made use of subtle interactional strategies in self-managing the likes of knowledge disagreements and social loafing. Such findings show that students do not always engage with (tutorless) PBL as intended, and provide a case for the continued naturalistic study of such conversational intricacies.

Women are able to train in arduous combat roles for the first time in the British military, yet data on sex differences in physiological responses to such physically demanding employment are lacking. Military women appear to experience high rates of fractures, menstrual disturbance and adverse psychological outcomes, conditions related to perturbations in metabolic and hormonal function. There is a paucity of studies investigating hypothalamic-pituitary-gonad (HPG) and hypothalamicpituitary-adrenal (HPA) axis function in military women. Low energy availability (EA) is an important cause of reproductive dysfunction and decreased bone mineral density (BMD) in athletes, while psychological stress and activation of the HPA axis are also associated with HPG axis suppression. Military training is physically demanding, psychologically stressful and frequently takes place in extreme climates. Therefore, the work in this thesis aimed to characterise female endocrine adaptations to arduous military in two settings: basic military training in the UK and highly arduous exercise in extreme cold. To address female responses to extreme heat, relative rates of heat illness (HI) among men and women were compared in a systematic review and meta-analysis. Female metabolic and endocrine adaptations to basic military training were explored in a cohort study of women undertaking the 11-month Commissioning Course at the Royal Military Academy, Sandhurst. Changes in body composition were measured by whole-body dual-energy-x-ray absorptiometry (DXA) at baseline and after 3, 7 and 11 months. Energy availability was assessed over 10-day periods using goldstandard techniques during months 3, 6 and 10 of training. Fasting blood sampling at baseline and after 7 and 11 months assessed leptin, insulin and glucose, as well as cortisol, cortisol binding globulin (CBG), oestradiol, anti-Müllerian hormone (AMH), inhibin B and bone turnover markers. Dynamic assessment of the HPG and HPA was undertaken using Combined Hypothalamic-pituitary-Ovarian and adrenal Cortex (CHOC) tests (LH/FSH and cortisol response to gonadotrophin releasing hormone (GnRH) and adrenocorticotrophic hormone, respectively, at five time points over 1 hour), at baseline and after 9 months. Psychological stress and mood were assessed regularly using questionnaires. Diurnal saliva cortisol was measured approximately every five weeks of training, and 1cm hair samples were assayed for cortisol to give an average monthly cortisol profile. A urinary progesterone: creatinine ratio cut-off was validated and used to determine if ovulation had taken place in women not using hormonal contraceptives, throughout the Commissioning Course. Changes in BMD were explored using DXA. Sixty one female Officer Cadets commenced the study (mean age 24.0 ±0.3 years) of whom 52 completed the study and the Course (8 withdrew due to musculoskeletal injuries; one changed career). Fat mass decreased 0.8kg from baseline to month 3 of training, increased 1.8kg to month 7 and reverted to baseline by month 11; fatfree mass did not change. Leptin and insulin resistance increased in association with fat mass. The assessment of EA was hampered by underreporting of energy intake by around 30%, however this measure of EA was weakly associated with physical performance, and paradoxically inversely associated with change in fat mass, suggesting compensatory over-eating after periods of arduous training and low energy intake. Questionnaires showed lower mood, increased stress and greater sleep deprivation during the course. Diurnal cortisol variability peaked in the first month of training, followed by habituation over the ensuing 10 months. Fasting plasma cortisol decreased, while CBG remained stable during the Course. Hair cortisol increased throughout, possibly reflecting physical exercise. Cortisol response to ACTH was modestly lower at 9 months than baseline. These data suggest a healthy overall response of the HPA axis to demonstrably arduous training. Of 22 participants (36%) not using hormonal contraceptives, 7 (32%) reported increased menstrual frequency and 7 (32%) reported amenorrhoea or oligomenorrhoea. Of cycles with corresponding urine concentrations, 80% were anovulatory. LH and FSH responses to GnRH were suppressed after 9 months and this effect was apparent in both users and non-users of hormonal contraceptives (regardless of type). Oestradiol, FSH and inhibin B increased during the course, but there was no change in AMH, suggesting hypothalamic suppression of the HPG axis and follicular dysgenesis. Bone turnover was modestly increased, reflected in higher markers of both bone formation and resorption after 8 and 11 months. Total BMD reduced slightly, with modest regional losses from arms, legs and ribs, while trunk, spine and pelvis BMD were preserved. The female response to arduous exercise in extreme cold was explored in six participants (median (range) 32.7 (28.6–36.1) years) undertaking the first unassisted all-female team crossing of Antarctica. The measures used above were adapted for use 1 month pre-expedition and 5 and 14 days post-expedition; no throughexpedition measurements were possible, and the CHOC test was performed after low-dose dexamethasone suppression. Mean (SD) weight loss was 10.1 (2.3) kg, constituting fat and not fat-free mass. Fasting oestradiol, cortisol and insulin resistance were unaffected, except leptin, which fell during the expedition and recovered partially after 14 days. Hair cortisol was elevated during the expedition. Cortisol, LH and FSH responsiveness were suppressed prior to the expedition, but were unchanged change immediately afterwards. LH responsiveness was higher than pre-expedition at expedition +14 days. Bone turnover was uncoupled immediately after the expedition, with higher resorption markers and lower formation markers, resolving after 14 days. Total BMD was unaffected. The systematic review and meta-analysis included data containing comparable male and female rates of HI. Incident rate ratios were calculated and adjusted, where possible, for severity, occupation and age. Contrary to expectations based on published laboratory studies of sex-related physiology, the systematic review of found consistently higher rates of HI reported among men than women. The metaanalysis found HI rates were over twice as high in men than women (mean (95% CI) incident risk ratio 2.28 (1.66-3.16)). This pattern was consistent across the age span and all severities of HI, and was greater in occupational HI than non-occupational HI (5.66 (2.53-13.64) vs 2.96 (2.14-4.10). In conclusion, this thesis demonstrated that women in basic military training do experience suppression of the HPG axis, despite long-term energy sufficiency with evidence of compensatory overeating and resilient HPA axis function. Resilient endocrine function in women who crossed Antarctica provides a proof of concept that with appropriate selection, nutrition and preparation, women can benefit from extremely arduous training. Women are also resilient to extreme heat, as evidenced by lower rates of HI than in men. The mechanism underlying reproductive dysfunction and associated pathology in women requires further elucidation but need not preclude women from entering such roles.