Generalized Geometry and M theory

We reformulate the Hamiltonian form of bosonic eleven dimensional supergravity in terms of an object that unifies the three-form and the metric. For the case of four spatial dimensions, the duality group is manifest and the metric and C-field are on an equal footing even though no dimensional reduction is required for our results to hold. One may also describe our results using the generalized geometry that emerges from membrane duality. The relationship between the twisted Courant algebra and the gauge symmetries of eleven dimensional supergravity are described in detail.Comment: 29 pages of Latex, v2 References added, typos fixed, v3 corrected kinetic term and references adde

Work-related stress:The impact of COVID-19 on critical care and redeployed nurses: A mixed-methods study

Lisa Salisbury - ORCID: 0000-0002-1400-3224 https://orcid.org/0000-0002-1400-3224Replaced AM with VoR 2021-07-08.Introduction: We need to understand the impact of COVID-19 on Critical Care (CCNs) and redeployed nurses and NHS organisations. Methods and analysis: This is a mixed methods study (QUANT – QUAL), underpinned by a theoretical model of occupational stress, the Job-Demand Resources Model (JD-R). Participants are critical care and redeployed nurses from Scottish and three large English units. Phase one is a cross-sectional survey in part replicating a pre-COVID-19 study and results will be compared with this data. Linear and logistic regression analysis will examine the relationship between antecedent, demographic, and professional variables on health impairment (burnout syndrome, mental health, posttraumatic stress symptoms), motivation (work engagement, commitment), and organisational outcomes (intention to remain in critical care nursing and quality of care). We will also assess the usefulness of a range of resources provided by the NHS and professional organisations. To allow in-depth exploration of individual experiences, phase two will be one-to-one semi-structured interviews with 25 CCNs and 10 redeployed nurses. The JD-R model will provide the initial coding framework to which the interview data will be mapped. The remaining content will be analysed inductively to identify and chart content that is not captured by the model. In this way the adequacy of the JD-R model is examined robustly and its expression in this context will be detailed. Ethics and dissemination: Ethics approval was granted from the University of Aberdeen CERB2020101993. We plan to disseminate findings at stakeholder events, publish in peer reviewed journals and at present at national and international conferences.https://doi.org/10.1136/bmjopen-2021-05132611pubpub

On the Riemann Tensor in Double Field Theory

Double field theory provides T-duality covariant generalized tensors that are natural extensions of the scalar and Ricci curvatures of Riemannian geometry. We search for a similar extension of the Riemann curvature tensor by developing a geometry based on the generalized metric and the dilaton. We find a duality covariant Riemann tensor whose contractions give the Ricci and scalar curvatures, but that is not fully determined in terms of the physical fields. This suggests that \alpha' corrections to the effective action require \alpha' corrections to T-duality transformations and/or generalized diffeomorphisms. Further evidence to this effect is found by an additional computation that shows that there is no T-duality invariant four-derivative object built from the generalized metric and the dilaton that reduces to the square of the Riemann tensor.Comment: 36 pages, v2: minor changes, ref. added, v3: appendix on frame formalism added, version to appear in JHE

Gauge fields and infinite chains of dualities

We show that the particle states of Maxwell's theory, in $D$ dimensions, can be represented in an infinite number of ways by using different gauge fields. Using this result we formulate the dynamics in terms of an infinite set of duality relations which are first order in space-time derivatives. We derive a similar result for the three form in eleven dimensions where such a possibility was first observed in the context of E11. We also give an action formulation for some of the gauge fields. In this paper we give a pedagogical account of the Lorentz and gauge covariant formulation of the irreducible representations of the Poincar\'e group, used previously in higher spin theories, as this plays a key role in our constructions. It is clear that our results can be generalised to any particle.Comment: 37 page

“Like fighting a fire with a water pistol”: A qualitative study of the work experiences of critical care nurses during the COVID ‐19 pandemic

From Wiley via Jisc Publications RouterHistory: received 2023-04-03, rev-recd 2023-05-19, accepted 2023-06-21, epub 2023-07-28Article version: VoRPublication status: PublishedFunder: Health Services and Delivery Research Programme; doi: http://dx.doi.org/10.13039/501100002001; Grant(s): NIHR132068Lisa Salisbury - ORCID: 0000-0002-1400-3224 https://orcid.org/0000-0002-1400-3224Aim: To understand the experience of critical care nurses during the COVID‐19 pandemic, through the application of the Job‐Demand‐Resource model of occupational stress. Design: Qualitative interview study. Methods: Twenty‐eight critical care nurses (CCN) working in ICU in the UK NHS during the COVID‐19 pandemic took part in semi‐structured interviews between May 2021 and May 2022. Interviews were guided by the constructs of the Job‐Demand Resource model. Data were analysed using framework analysis. Results: The most difficult job demands were the pace and amount, complexity, physical and emotional effort of their work. Prolonged high demands led to CCN experiencing emotional and physical exhaustion, burnout, post‐traumatic stress symptoms and impaired sleep. Support from colleagues and supervisors was a core job resource. Sustained demands and impaired physical and psychological well‐being had negative organizational consequences with CCN expressing increased intention to leave their role. Conclusions: The combination of high demands and reduced resources had negative impacts on the psychological well‐being of nurses which is translating into increased consideration of leaving their profession. Implications for the Profession and/or Patient Care: The full impacts of the pandemic on the mental health of CCN are unlikely to resolve without appropriate interventions. Impact: Managers of healthcare systems should use these findings to inform: (i) the structure and organization of critical care workplaces so that they support staff to be well, and (ii) supportive interventions for staff who are carrying significant psychological distress as a result of working during and after the pandemic. These changes are required to improve staff recruitment and retention. Reporting Method: We used the COREQ guidelines for reporting qualitative studies. Patient and Public Contribution: Six CCN provided input to survey content and interview schedule. Two authors and members of the study team (T.S. and S.C.) worked in critical care during the pandemic.pubpu

Partition Functions for Maxwell Theory on the Five-torus and for the Fivebrane on S1XT5

We compute the partition function of five-dimensional abelian gauge theory on a five-torus T5 with a general flat metric using the Dirac method of quantizing with constraints. We compare this with the partition function of a single fivebrane compactified on S1 times T5, which is obtained from the six-torus calculation of Dolan and Nappi. The radius R1 of the circle S1 is set to the dimensionful gauge coupling constant g^2= 4\pi^2 R1. We find the two partition functions are equal only in the limit where R1 is small relative to T5, a limit which removes the Kaluza-Klein modes from the 6d sum. This suggests the 6d N=(2,0) tensor theory on a circle is an ultraviolet completion of the 5d gauge theory, rather than an exact quantum equivalence.Comment: v4, 37 pages, published versio

“Like fighting a fire with a water pistol”: A qualitative study of the work experiences of critical care nurses during the COVID‐19 pandemic

AimTo understand the experience of critical care nurses during the COVID-19 pandemic, through the application of the Job-Demand-Resource model of occupational stress.DesignQualitative interview study.MethodsTwenty-eight critical care nurses (CCN) working in ICU in the UK NHS during the COVID-19 pandemic took part in semi-structured interviews between May 2021 and May 2022. Interviews were guided by the constructs of the Job-Demand Resource model. Data were analysed using framework analysis.ResultsThe most difficult job demands were the pace and amount, complexity, physical and emotional effort of their work. Prolonged high demands led to CCN experiencing emotional and physical exhaustion, burnout, post-traumatic stress symptoms and impaired sleep. Support from colleagues and supervisors was a core job resource. Sustained demands and impaired physical and psychological well-being had negative organizational consequences with CCN expressing increased intention to leave their role.ConclusionsThe combination of high demands and reduced resources had negative impacts on the psychological well-being of nurses which is translating into increased consideration of leaving their profession.Implications for the Profession and/or Patient CareThe full impacts of the pandemic on the mental health of CCN are unlikely to resolve without appropriate interventions.ImpactManagers of healthcare systems should use these findings to inform: (i) the structure and organization of critical care workplaces so that they support staff to be well, and (ii) supportive interventions for staff who are carrying significant psychological distress as a result of working during and after the pandemic. These changes are required to improve staff recruitment and retention.Reporting MethodWe used the COREQ guidelines for reporting qualitative studies.Patient and Public ContributionSix CCN provided input to survey content and interview schedule. Two authors and members of the study team (T.S. and S.C.) worked in critical care during the pandemic

Off-shell superconformal nonlinear sigma-models in three dimensions

We develop superspace techniques to construct general off-shell N=1,2,3,4 superconformal sigma-models in three space-time dimensions. The most general N=3 and N=4 superconformal sigma-models are constructed in terms of N=2 chiral superfields. Several superspace proofs of the folklore statement that N=3 supersymmetry implies N=4 are presented both in the on-shell and off-shell settings. We also elaborate on (super)twistor realisations for (super)manifolds on which the three-dimensional N-extended superconformal groups act transitively and which include Minkowski space as a subspace.Comment: 67 pages; V2: typos corrected, one reference added, version to appear on JHE

A randomised controlled trial evaluating a rehabilitation complex intervention for patients following intensive care discharge: the RECOVER study

Introduction: Patients who survive an intensive care unit admission frequently suffer physical and psychological morbidity for many months after discharge. Current rehabilitation pathways are often fragmented and little is known about the optimum method of promoting recovery. Many patients suffer reduced quality of life.Methods and analysis: The authors plan a multicentre randomised parallel group complex intervention trial with concealment of group allocation from outcome assessors. Patients who required more than 48 h of mechanical ventilation and are deemed fit for intensive care unit discharge will be eligible. Patients with primary neurological diagnoses will be excluded. Participants will be randomised into one of the two groups: the intervention group will receive standard ward-based care delivered by the NHS service with additional treatment by a specifically trained generic rehabilitation assistant during ward stay and via telephone contact after hospital discharge and the control group will receive standard ward-based care delivered by the current NHS service. The intervention group will also receive additional information about their critical illness and access to a critical care physician. The total duration of the intervention will be from randomisation to 3 months postrandomisation. The total duration of follow-up will be 12 months from randomisation for both groups. The primary outcome will be the Rivermead Mobility Index at 3 months. Secondary outcomes will include measures of physical and psychological morbidity and function, quality of lifeand survival over a 12-month period. A health economic evaluation will also be undertaken. Groups will be compared in relation to primary and secondary outcomes; quantitative analyses will be supplemented by focus groups with patients, carers and healthcare workers.Ethics and dissemination: Consent will be obtained from patients and relatives according to patient capacity. Data will be analysed accordingto a predefined analysis plan