Solutions to the reconstruction problem in asymptotic safety

Starting from a full renormalised trajectory for the effective average action (a.k.a. infrared cutoff Legendre effective action) $\Gamma_k$, we explicitly reconstruct corresponding bare actions, formulated in one of two ways. The first step is to construct the corresponding Wilsonian effective action $S^k$ through a tree-level expansion in terms of the vertices provided by $\Gamma_k$. It forms a perfect bare action giving the same renormalised trajectory. A bare action with some ultraviolet cutoff scale $\Lambda$ and infrared cutoff $k$ necessarily produces an effective average action $\Gamma^\Lambda_k$ that depends on both cutoffs, but if the already computed $S^\Lambda$ is used, we show how $\Gamma^\Lambda_k$ can also be computed from $\Gamma_k$ by a tree-level expansion, and that $\Gamma^\Lambda_k\to\Gamma_k$ as $\Lambda\to\infty$. Along the way we show that Legendre effective actions with different UV cutoff profiles, but which correspond to the same Wilsonian effective action, are related through tree-level expansions. All these expansions follow from Legendre transform relationships that can be derived from the original one between $\Gamma^\Lambda_k$ and $S^k$.Comment: 32 page

The experience and impact of traumatic perinatal event experiences in midwives: A qualitative investigation

Background: Through their work midwives may experience distressing events that fulfil criteria for trauma. However, there is a paucity of research examining the impact of these events, or what is perceived to be helpful/unhelpful by midwives afterwards. Objective: To investigate midwives’ experiences of traumatic perinatal events and to provide insights into experiences and responses reported by midwives with and without subsequent posttraumatic stress symptoms. Design: Semi-structured telephone interviews were conducted with a purposive sample of midwives following participation in a previous postal survey. Methods: 35 midwives who had all experienced a traumatic perinatal event defined using the Diagnostic and Statistical Manual of Mental Disorders (version IV) Criterion A for posttraumatic stress disorder were interviewed. Two groups of midwives with high or low distress (as reported during the postal survey) were purposefully recruited. High distress was defined as the presence of clinical levels of PTSD symptomatology and high perceived impairment in terms of impacts on daily life. Low distress was defined as any symptoms of PTSD present were below clinical threshold and low perceived life impairment. Interviews were analysed using template analysis, an iterative process of organising and coding qualitative data chosen for this study for its flexibility. An initial template of four a priori codes was used to structure the analysis: event characteristics, perceived responses and impacts, supportive and helpful strategies and reflection of change over time codes were amended, integrated and collapsed as appropriate through the process of analysis. A final template of themes from each group is presented together with differences outlined where applicable. Results: Event characteristics were similar between groups, and involved severe, unexpected episodes contributing to feeling ‘out of a comfort zone.’ Emotional upset, self-blame and feelings of vulnerability to investigative procedures were reported. High distress midwives were more likely to report being personally upset by events and to perceive all aspects of personal and professional lives to be affected. Both groups valued talking about the event with peers, but perceived support from senior colleagues and supervisors to be either absent or inappropriate following their experience; however, those with high distress were more likely to endorse this view and report a perceived need to seek external input. Conclusion: Findings indicate a need to consider effective ways of promoting and facilitating access to support, at both a personal and organisational level, for midwives following the experience of a traumatic perinatal event

What are the characteristics of perinatal events perceived to be traumatic by midwives?

Objective: there is potential for midwives to indirectly experience events whilst providing clinical care that fulfil criteria for trauma. This research aimed to investigate the characteristics of events perceived as traumatic by UK midwives. Methods: as part of a postal questionnaire survey conducted between December 2011 and April 2012, midwives (n=421) who had witnessed and/or listened to an account of an event and perceived this as traumatic for themselves provided a written description of their experience. A traumatic perinatal event was defined as occurring during labour or shortly after birth where the midwife perceived the mother or her infant to be at risk, and they (the midwife) had experienced fear, helplessness or horror in response. Descriptions of events were analysed using thematic analysis. Witnessed (W; n=299) and listened to (H; n=383) events were analysed separately and collated to identify common and distinct themes across both types of exposure. Findings: six themes were identified, each with subthemes. Five themes were identified in both witnessed and listened to accounts and one was salient to witnessed accounts only. Themes indicated that events were characterised as severe, unexpected and complex. They involved aspects relating to the organisational context; typically limited or delayed access to resources or personnel. There were aspects relating to parents, such as having an existing relationship with the parents, and negative perceptions of the conduct of colleagues. Traumatic events had a common theme of generating feelings of responsibility and blame Finally for witnessed events those that were perceived as traumatic sometimes held personal salience, so resonated in some way with the midwife's own life experience Key conclusions: midwives are exposed to events as part of their work that they may find traumatic. Understanding the characteristics of the events that may trigger this perception may facilitate prevention of any associated distress and inform the development of supportive interventions