Modelling the Non-equilibrium Electric Double Layer at Oil-pressboard Interface of High Voltage Transformers

In large oil-filled power transformers, cellulose-based pressboard and paper are used throughout for electrical insulation. Microscopic views have shown that pressboard insulation is a fibrous and porous structure with non-homogeneous surface. It has been recognised that the pressboard structure is more porous towards the edge [1]. The pores within the pressboard allow oil absorption during impregnation process and provide paths for oil to penetrate until saturation is reached. The ratio of fibre and oil changes as the material structure changes from a medium of bulk oil-pressboard composite toward the bulk oil medium. The porosity of pressboard can also result in impurities within the oil being drawn into the pressboard. It has also been recognised that physicochemical process of a liquid in contact with solid wall leads to the formation of electric double layer (EDL) in the liquid region [2, 3]. The material properties and geometry of pressboard thus lead to a complex oil-pressboard interface. A 2-D model of oil-pressboard interface has been constructed using Comsol Multiphysics Finite Element Analysis software and this is shown in Figure 1. The mathematical model considers the dissociation of a generic impurity in the oil into positive and negative ions and considers the role of the porous and non-homogeneous wall of pressboard in the formation of the EDL. The pressboard, which is represented by different arrays of fibre, promotes preferential adsorption and desorption processes between ions in the oil and unoccupied fibre surfaces of oil impregnated pressboard. The model studies the non-equilibrium charge density profile in the EDL at the oil-pressboard interface when the oil is in the stationary condition

Alteration of Electroencephalographic Responses to Castration in Cats by Administration of Opioids

The aim of this study was to investigate the effect of opioids on electroencephalogram (EEG) indices of nociception in cats undergoing castration. Cats were randomly assigned to receive one of the four treatments (n=8); 0.2 mg/kg morphine, 0.005 mg/ kg fentanyl, 0.01 mg/kg buprenorphine or 0.2 mg/kg butorphanol, administered subcutaneously (SC) at the time of pre-anesthetic medication. Anesthesia was induced with intravenous propofol and maintained with halothane in oxygen. EEG was recorded continuously in a three electrode montage. Median frequency (F50), total power (PTOT) and 95% spectral edge frequency (F95) derived from the EEG power spectra recorded prior to skin incision (baseline) were compared with those recorded during the ligation of the spermatic cords of both testicles. During the ligation of testicle 1, the mean F50 of cats that received buprenorphine and butorphanol was significantly (p0.05). These results indicate that opioid analgesics, acting at different opioid receptors with variable affinity, produce changes in the EEG responses that reflect their anti-nociceptive efficacy. This study demonstrates the usefulness of the EEG as a valid tool for evaluating analgesic efficacy in cats, as shown in other species of animals in previous studies

Storage capacity of a constructive learning algorithm

Upper and lower bounds for the typical storage capacity of a constructive algorithm, the Tilinglike Learning Algorithm for the Parity Machine [M. Biehl and M. Opper, Phys. Rev. A {\bf 44} 6888 (1991)], are determined in the asymptotic limit of large training set sizes. The properties of a perceptron with threshold, learning a training set of patterns having a biased distribution of targets, needed as an intermediate step in the capacity calculation, are determined analytically. The lower bound for the capacity, determined with a cavity method, is proportional to the number of hidden units. The upper bound, obtained with the hypothesis of replica symmetry, is close to the one predicted by Mitchinson and Durbin [Biol. Cyber. {\bf 60} 345 (1989)].Comment: 13 pages, 1 figur

Missing the human connection: A rapid appraisal of healthcare workers' perceptions and experiences of providing palliative care during the COVID-19 pandemic.

BACKGROUND: During infectious epidemics, healthcare workers are required to deliver traditional care while facing new pressures. Time and resource restrictions, a focus on saving lives and new safety measures can lead to traditional aspects of care delivery being neglected. AIM: Identify barriers to delivering end-of-life care, describe attempts to deliver care during the COVID-19 pandemic, and understand the impact this had on staff. DESIGN: A rapid appraisal was conducted incorporating a rapid review of policies from the United Kingdom, semi-structured telephone interviews with healthcare workers, and a review of mass print media news stories and social media posts describing healthcare worker's experiences of delivering care during the pandemic. Data were coded and analysed using framework analysis. SETTING/PARTICIPANTS: From a larger ongoing study, 22 interviews which mentioned death or caring for patients at end-of-life, eight government and National Health Service policies affecting end-of-life care delivery, eight international news media stories and 3440 publicly available social media posts were identified. The social media analysis centred around 274 original tweets with the highest reach, engagement and relevance. Incorporating multiple workstreams provided a broad perspective of end-of-life care during the COVID-19 pandemic in the United Kingdom. RESULTS: Three themes were developed: (1) restrictions to traditional care, (2) striving for new forms of care and (3) establishing identity and resilience. CONCLUSIONS: The COVID-19 pandemic prohibited the delivery of traditional care as practical barriers restricted human connections. Staff prioritised communication and comfort orientated tasks to re-establish compassion at end-of-life and displayed resilience by adjusting their goals

Do Black, Asian and Minority Ethnic nurses and midwives experience a career delay? A cross-sectional survey investigating career progression barriers

Background Black, Asian and Minority Ethnic nurses and midwives are under-represented in higher and managerial roles. Aims This study explored the presence and nature of career progression delays for Black, Asian and Minority Ethnic nurses and midwives and investigated where the barriers to progression were. Design A secondary analysis of data from a wider cross-sectional survey investigating workplace experiences, burnout and patient safety in nurses and midwives. Methods 538 nurses and midwives were recruited from four UK hospitals between February and March 2017. A career progression delay was viewed as being present if Black, Asian and Minority Ethnic nurses and midwives had spent longer on the entry level nursing grade and less time on higher grades in the previous 10 years. The analysis included items pertaining to: receipt of professional training, perceived managerial support for progression, likelihood of submitting applications and application success rates. Data were analysed using linear regression, odds ratios and t-tests. Results were reported using the STROBE Checklist. Results Black, Asian and Minority Ethnic nurses and midwives (n = 104; 19.4%) had spent more months working at the entry-level grade (M = 75.75, SD = 44.90) than White nurses and midwives (n = 428; 79.7%; M = 41.85, SD = 44.02, p < 0.001) and fewer months at higher grades (M = 15.29, SD = 30.94 v 29.33, SD = 39.78, p = 0.006 at Band 6; M = 6.54, SD = 22.59 v M = 19.68, SD = 37.83, p = 0.001 at Band 7) over the previous 10 years. Black, Asian and Minority Ethnic nurses and midwives were less likely to have received professional training in the previous year (N = 53; 53.0% v N = 274; 66.0%, p = 0.015) and had to apply for significantly more posts than White nurses and midwives before gaining their first post on their current band (M = 1.22, SD = 1.51 v M = 0.81, SD = 1.55, p = 0.026). Conclusions Interventions are needed to improve racial equality regarding career progression in nurses and midwives. Increasing access to professional training and reducing discriminatory practice in job recruitment procedures may be beneficial

Re-ordering connections: UK healthcare workers' experiences of emotion management during the COVID-19 pandemic

This paper examines the impact of disruptions to the organisation and delivery of healthcare services and efforts to re-order care through emotion management during the COVID-19 pandemic in the UK. Framing care as an affective practice, studying healthcare workers' (HCWs) experiences enables better understanding of how interactions between staff, patients and families changed as a result of the pandemic. Using a rapid qualitative research methodology, we conducted interviews with frontline HCWs in two London hospitals during the peak of the first wave of the pandemic and sourced public accounts of HCWs' experiences of the pandemic from social media (YouTube and Twitter). We conducted framework analysis to identify key factors disrupting caring interactions. Fear of infection and the barriers of physical distancing acted to separate staff from patients and families, requiring new affective practices to repair connections. Witnessing suffering was distressing for staff, and providing a 'good death' for patients and communicating care to families was harder. In addition to caring for patients and families, HCWs cared for each other. Infection control measures were important for limiting the spread of COVID-19 but disrupted connections that were integral to care, generating new work to re-order interactions

Perceptions and experiences of healthcare workers during the COVID-19 pandemic in the UK

OBJECTIVE: The COVID-19 pandemic has set unprecedented demand on the healthcare workforce around the world. The UK has been one of the most affected countries in Europe. The aim of this study was to explore the perceptions and experiences of healthcare workers (HCWs) in relation to COVID-19 and care delivery models implemented to deal with the pandemic in the UK. METHODS: The study was designed as a rapid appraisal combining: (1) a review of UK healthcare policies (n=35 policies), (2) mass media and social media analysis of front-line staff experiences and perceptions (n=101 newspaper articles, n=1 46 000 posts) and (3) in-depth (telephone) interviews with front-line staff (n=30 interviews). The findings from all streams were analysed using framework analysis. RESULTS: Limited personal protective equipment (PPE) and lack of routine testing created anxiety and distress and had a tangible impact on the workforce. When PPE was available, incorrect size and overheating complicated routine work. Lack of training for redeployed staff and the failure to consider the skills of redeployed staff for new areas were identified as problems. Positive aspects of daily work reported by HCWs included solidarity between colleagues, the establishment of well-being support structures and feeling valued by society. CONCLUSION: Our study highlighted the importance of taking into consideration the experiences and concerns of front-line staff during a pandemic. Staff working in the UK during the COVID-19 pandemic advocated clear and consistent guidelines, streamlined testing of HCWs, administration of PPE and acknowledgement of the effects of PPE on routine practice

Perceptions and experiences of healthcare workers during the COVID-19 pandemic in the UK

Objective The COVID-19 pandemic has set unprecedented demand on the healthcare workforce around the world. The UK has been one of the most affected countries in Europe. The aim of this study was to explore the perceptions and experiences of healthcare workers (HCWs) in relation to COVID-19 and care delivery models implemented to deal with the pandemic in the UK. Methods The study was designed as a rapid appraisal combining: (1) a review of UK healthcare policies (n=35 policies), (2) mass media and social media analysis of front-line staff experiences and perceptions (n=101 newspaper articles, n=1 46 000 posts) and (3) in-depth (telephone) interviews with front-line staff (n=30 interviews). The findings from all streams were analysed using framework analysis. Results Limited personal protective equipment (PPE) and lack of routine testing created anxiety and distress and had a tangible impact on the workforce. When PPE was available, incorrect size and overheating complicated routine work. Lack of training for redeployed staff and the failure to consider the skills of redeployed staff for new areas were identified as problems. Positive aspects of daily work reported by HCWs included solidarity between colleagues, the establishment of well-being support structures and feeling valued by society. Conclusion Our study highlighted the importance of taking into consideration the experiences and concerns of front-line staff during a pandemic. Staff working in the UK during the COVID-19 pandemic advocated clear and consistent guidelines, streamlined testing of HCWs, administration of PPE and acknowledgement of the effects of PPE on routine practice

The co-evolution of the genome and epigenome in colorectal cancer.

Colorectal malignancies are a leading cause of cancer-related death1 and have undergone extensive genomic study2,3. However, DNA mutations alone do not fully explain malignant transformation4-7. Here we investigate the co-evolution of the genome and epigenome of colorectal tumours at single-clone resolution using spatial multi-omic profiling of individual glands. We collected 1,370 samples from 30 primary cancers and 8 concomitant adenomas and generated 1,207 chromatin accessibility profiles, 527 whole genomes and 297 whole transcriptomes. We found positive selection for DNA mutations in chromatin modifier genes and recurrent somatic chromatin accessibility alterations, including in regulatory regions of cancer driver genes that were otherwise devoid of genetic mutations. Genome-wide alterations in accessibility for transcription factor binding involved CTCF, downregulation of interferon and increased accessibility for SOX and HOX transcription factor families, suggesting the involvement of developmental genes during tumourigenesis. Somatic chromatin accessibility alterations were heritable and distinguished adenomas from cancers. Mutational signature analysis showed that the epigenome in turn influences the accumulation of DNA mutations. This study provides a map of genetic and epigenetic tumour heterogeneity, with fundamental implications for understanding colorectal cancer biology