A random matrix decimation procedure relating β=2/(r+1)\beta = 2/(r+1) to β=2(r+1)\beta = 2(r+1)

Classical random matrix ensembles with orthogonal symmetry have the property that the joint distribution of every second eigenvalue is equal to that of a classical random matrix ensemble with symplectic symmetry. These results are shown to be the case $r=1$ of a family of inter-relations between eigenvalue probability density functions for generalizations of the classical random matrix ensembles referred to as $\beta$-ensembles. The inter-relations give that the joint distribution of every $(r+1)$-st eigenvalue in certain $\beta$-ensembles with $\beta = 2/(r+1)$ is equal to that of another $\beta$-ensemble with $\beta = 2(r+1)$. The proof requires generalizing a conditional probability density function due to Dixon and Anderson.Comment: 19 pages, 1 figur

2004 How confident are we in decision making? The quantitative analysis of ambulance response to older adult fallers: A pilot survey

Introduction The number one reason for older people to be taken to hospital emergency departments is a fall1. An “Ambulance Improvement Programme Pillar”2 is trying to reduce conveyance to hospital for falls, however it is not understood how the attending clinician’s confidence impacts decision-making. The objectives were to assess recruitment rate and feasibility of online survey delivery, and determine the experiences and confidence of frontline emergency clinicians in attending older adults who have fallen. Method Online cross-sectional survey, undertaken in one English ambulance service in May 2023. Items included participant demographics and 5-point Likert scales of confidence. Data were summarised using descriptive statistics and Chi-square analyses to compare confidence between localities and years’ experience. Results 81 responses were received from across the regional ambulance service’s 16 localities, supporting online survey delivery to be feasible in this population. 76% of respondents were paramedics, and 53% were aged 25-34. 60% of respondents rated being ‘Somewhat confident’ in assessing older adults who have fallen, with responses ranging between ‘Neither confident nor unconfident’ to ‘Completely confident’. No significant difference was found between the locality and confidence levels for assessing this patient population. However, there appeared to be significant variation between confidence levels relating to utilisation of hospital pathways and localities (p-value=.0045). Length of experience in both frontline ambulance and overall healthcare provision was not significantly associated with different levels of confidence. Conclusion Online survey delivery is an effective method in this population. Locality of work had a relationship with confidence in utilising hospital avoidance pathways, however, it did not relate to assessing this population. Confidence levels were not found to be related to the number of years providing care. References 1. Dewhirst. (2023). National Falls Prevention Coordination Group. https://committees.parliament.uk/writtenevidence/117837/pdf/ 2. NHS England and NHS Improvement. (2019). Ambulance Improvement Programme. https://www.england.nhs.uk/wp-content/uploads/2019/09/planning-to-safetly-reduce-avoidable-conveyance-v4.0.pd

2005 How do emergency ambulance clinicians decide what to do for older adults who have fallen? An analysis of qualitative survey data

Introduction Around 10% of calls received by English ambulance services are for older adults who have fallen1; with an ageing population there are significant care provision needs. Decision-making on the treatment for people who fall, can impact their future physical and mental health. Previous research in decision-making of ambulance staff found perception of role, confidence, service demands and training to be key drivers2. The previous work highlighting drivers, but not the experiences that explain why they occur, leads this study aim to determine the experiences and confidence of frontline emergency clinicians in attending older adults who have fallen. Method Online cross-sectional survey of frontline emergency clinicians from one English ambulance service in May 2023. Open questions generated qualitative data for thematic analysis3. Ethical and regulatory approvals, and informed consent, were obtained. Results: 81 participants completed the survey. Analysis identified three themes. Care Provision: Provision of hospital avoidance pathways varies throughout the region. Concerns arose from not knowing what different areas had and reduced accessibility out of hours. Communication: Decision-making confidence was impacted by the participants’ experiences; positive experiences encouraged use of hospital avoidance pathways, whilst negative experiences impeded willingness to avoid hospital for fear of repercussion. Shared Decision-Making: Patients, family and clinicians were all valued as part of shared decision-making, with past feedback on decision-making informing future practice. Conclusion Confidence of frontline ambulance staff was impacted by the challenge of a regional and 24/7 ambulance service not having consistent pathways available. This variation led to concerns when responding to patients outside of the clinician’s usual area, and further challenges ambulance clinicians must balance in their practice. References 1. Snooks, Anthony, Chatters. et al. Health Technology Assessment 2017; 21: 1–218. 2. Simpson, Thomas, Bendall. et al. BMC Health Services Research. 2017; 17: 299. 3. Braun and Clarke. (2022) Thematic Analysis: A practical guide

Quantum Dissipation and Decay in Medium

Quantum dissipation in thermal environment is investigated, using the path integral approach. The reduced density matrix of the harmonic oscillator system coupled to thermal bath of oscillators is derived for arbitrary spectrum of bath oscillators. Time evolution and the end point of two-body decay of unstable particles is then elucidated: After early transient times unstable particles undergo the exponential decay, followed by the power law decay and finally ending in a mixed state of residual particles containing contributions from both on and off the mass shell, whose abundance does not suffer from the Boltzmann suppression.Comment: 19 pages, LATEX file. Substantially expanded and revised for publication, including more complete description of application to unstable particle decay in thermal medium. Some minor mistake of numerical factors correcte

Is a definitive trial of prehospital continuous positive airway pressure versus standard oxygen therapy for acute respiratory failure indicated? The ACUTE pilot randomised controlled trial

Objectives To determine the feasibility of a large-scale definitive multicentre trial of prehospital continuous positive airway pressure (CPAP) in acute respiratory failure. Design A single-centre, open-label, individual patient randomised, controlled, external pilot trial. Setting A single UK Ambulance Service, between August 2017 and July 2018. Participants Adults with respiratory distress and peripheral oxygen saturations below British Thoracic Society target levels despite controlled oxygen treatment. Interventions Patients were randomised to prehospital CPAP (O-Two system) versus standard oxygen therapy in a 1:1 ratio using simple randomisation. Primary and secondary outcome measures Feasibility outcomes comprised recruitment rate, adherence to allocated treatment, retention and data completeness. The primary clinical outcome was 30-day mortality. Results 77 patients were enrolled (target 120), including 7 cases with a diagnosis where CPAP could be ineffective or harmful. CPAP was fully delivered in 74% (target 75%). There were no major protocol violations. Full data were available for all key outcomes (targets ≥90%). Overall 30-day mortality was 27.3%. Of these deceased patients, 14/21 (68%) either did not have a respiratory condition or had ceiling of treatment decisions implemented excluding hospital non-invasive ventilation and critical care. Conclusions Recruitment rate was below target and feasibility was not demonstrated. Limited compliance with CPAP, and difficulty in identifying patients who could benefit from CPAP, indicate that prehospital CPAP is unlikely to materially reduce mortality. A definitive effectiveness trial of CPAP is therefore not recommended. Trial registration number ISRCTN12048261; Post-results

Seasonal influenza vaccine effectiveness in people with asthma: a national test-negative design case-control study

Financial support. The work was funded by the Chief Scientist Office of the Scottish Government under the grant (AUKCAR/14/03) and the NIHR–Health Technology Assessment (HTA) Programme (13/34/14) for the Seasonal Influenza Vaccination Effectiveness II (SIVE II) study. As principal investigator, C. R. S. received a grant for the SIVE-II project from the NIHR HTA. This work was carried out with the support of the Asthma UK Centre for Applied Research (AUK-AC-2012-01), the Farr Institute (MR/M501633/2), Health Data Research UK (an initiative funded by UK Research and Innovation, Department of Health and Social Care England and the devolved administrations and leading medical research charities), the European Union’s Horizon 2020 research and innovation programme (under grant agreement No 634446) and European Centre for Disease Prevention and Control (Influenza-Monitoring Vaccine Effectiveness). Acknowledgments. The authors thank and acknowledge all colleagues at the Asthma UK Centre for Applied Research for their support in this study. Disclaimer. The funding bodies had no role in the design of the study, review process, analysis, interpretation, or reporting of data. The views and opinions expressed herein are those of the authors and do not necessarily reflect those of the Health Technology Assessment Programme, National Institute for Health Research (NIHR), National Health Service, or the Department of Health. Potential conflicts of interest. The authors: No reported conflicts of interest. All authors have submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Conflicts that the editors consider relevant to the content of the manuscript have been disclosed.Peer reviewedPublisher PDFPublisher PD

Effectiveness of seasonal influenza vaccine in preventing laboratory-confirmed influenza in primary care in the United Kingdom : 2015/16 mid-season results

In 2015/16, the influenza season in the United Kingdom was dominated by influenza A(H1N1)pdm09 circulation. Virus characterisation indicated the emergence of genetic clusters, with the majority antigenically similar to the current influenza A(H1N1)pdm09 vaccine strain. Mid-season vaccine effectiveness (VE) estimates show an adjusted VE of 41.5% (95% confidence interval (CI): 3.0–64.7) against influenza-confirmed primary care consultations and of 49.1% (95% CI: 9.3–71.5) against influenza A(H1N1)pdm09. These estimates show levels of protection similar to the 2010/11 season, when this strain was first used in the seasonal vaccine

The ACOS CO_2 retrieval algorithm – Part 1: Description and validation against synthetic observations

This work describes the NASA Atmospheric CO_2 Observations from Space (ACOS) X_(CO_2) retrieval algorithm, and its performance on highly realistic, simulated observations. These tests, restricted to observations over land, are used to evaluate retrieval errors in the face of realistic clouds and aerosols, polarized non-Lambertian surfaces, imperfect meteorology, and uncorrelated instrument noise. We find that post-retrieval filters are essential to eliminate the poorest retrievals, which arise primarily due to imperfect cloud screening. The remaining retrievals have RMS errors of approximately 1 ppm. Modeled instrument noise, based on the Greenhouse Gases Observing SATellite (GOSAT) in-flight performance, accounts for less than half the total error in these retrievals. A small fraction of unfiltered clouds, particularly thin cirrus, lead to a small positive bias of ~0.3 ppm. Overall, systematic errors due to imperfect characterization of clouds and aerosols dominate the error budget, while errors due to other simplifying assumptions, in particular those related to the prior meteorological fields, appear small

Effectiveness of seasonal influenza vaccine in preventing laboratory-confirmed influenza in primary care in the United Kingdom : 2014/15 end of season results

The 2014/15 influenza season in the United Kingdom (UK) was characterised by circulation of predominantly antigenically and genetically drifted influenza A(H3N2) and B viruses. A universal paediatric influenza vaccination programme using a quadrivalent live attenuated influenza vaccine (LAIV) has recently been introduced in the UK. This study aims to measure the end-of-season influenza vaccine effectiveness (VE), including for LAIV, using the test negative case–control design. The overall adjusted VE against all influenza was 34.3% (95% confidence interval (CI) 17.8 to 47.5); for A(H3N2) 29.3% (95% CI: 8.6 to 45.3) and for B 46.3% (95% CI: 13.9 to 66.5). For those aged under 18 years, influenza A(H3N2) LAIV VE was 35% (95% CI: −29.9 to 67.5), whereas for influenza B the LAIV VE was 100% (95% CI:17.0 to 100.0). Although the VE against influenza A(H3N2) infection was low, there was still evidence of significant protection, together with moderate, significant protection against drifted circulating influenza B viruses. LAIV provided non-significant positive protection against influenza A, with significant protection against B. Further work to assess the population impact of the vaccine programme across the UK is underway

Variability and pathogenicity of hepatitis E virus genotype 3 variants

Infection with hepatitis E virus (HEV) can be clinically inapparent or produce symptoms and signs of hepatitis of varying severity and occasional fatality. This variability in clinical outcomes may reflect differences in host susceptibility or the presence of virally encoded determinants of pathogenicity. Analysis of complete genome sequences supports the division of HEV genotype 3 (HEV-3) variants into three major clades: 3ra comprising HEV isolates from rabbits, and 3efg and 3abchij comprising the corresponding named subtypes derived from humans and pigs. Using this framework, we investigated associations between viral genetic variability of HEV-3 in symptomatic and asymptomatic infections by comparing HEV-3 subgenomic sequences previously obtained from blood donors with those from patients presenting with hepatitis in the UK (54 blood donors, 148 hepatitis patients), the Netherlands (38 blood donors, 119 hepatitis patients), France (24 blood donors, 55 hepatitis patients) and Germany (14 blood donors, 36 hepatitis patients). In none of these countries was evidence found for a significant association between virus variants and patient group (P>0.05 Fisher's exact test). Furthermore, within a group of 123 patients in Scotland with clinically apparent HEV infections, we found no evidence for an association between variants of HEV-3 and disease severity or alanine aminotransferase level. The lack of detectable virally encoded determinants of disease outcomes in HEV-3 infection implies a more important role for host factors in its clinical phenotype