405 research outputs found
Competition of Mesoscales and Crossover to Tricriticality in Polymer Solutions
We show that the approach to asymptotic fluctuation-induced critical behavior
in polymer solutions is governed by a competition between a correlation length
diverging at the critical point and an additional mesoscopic length-scale, the
radius of gyration. Accurate light-scattering experiments on polystyrene
solutions in cyclohexane with polymer molecular weights ranging from 200,000 up
to 11.4 million clearly demonstrate a crossover between two universal regimes:
a regime with Ising asymptotic critical behavior, where the correlation length
prevails, and a regime with tricritical theta-point behavior determined by a
mesoscopic polymer-chain length.Comment: 4 pages in RevTeX with 4 figure
Drag and jet quenching of heavy quarks in a strongly coupled N=2* plasma
The drag of a heavy quark and the jet quenching parameter are studied in the
strongly coupled N=2* plasma using the AdS/CFT correspondence. Both increase in
units of the spatial string tension as the theory departs from conformal
invariance. The description of heavy quark dynamics using a Langevin equation
is also considered. It is found that the difference between the velocity
dependent factors of the transverse and longitudinal momentum broadening of the
quark admit an interpretation in terms of relativistic effects, so the
distribution is spherical in the quark rest frame. When conformal invariance is
broken there is a broadening of the longitudinal momentum distribution. This
effect may be useful in understanding the jet distribution observed in
experiments.Comment: 30 pages, 5 figures, references added, minor corrections. To be
published in JHE
Working conditions and well-being across the COVID pandemic in UK social (care) workers
Prior to the COVID-19 pandemic, social work and social care practitioners had some the worst working conditions of any sector in the UK. During the pandemic, data revealed that social care occupations had higher COVID infection and mortality rates than the general population. The article reports the changing working conditions (measured via the Work-Related Quality of Life scale) and well-being (measured via the Short Warwich–Edinburgh Mental Well-being Scale) of UK social care and social workers across three timepoints between May 2020 and July 2021 through an online cross-sectional survey of working conditions and well-being. Analysis of variance demonstrated that both well-being and working conditions were significantly poorer in July 2021 (phase 3 [n = 1,606]) than the previous two phases (n = 2,523 and n = 2,424, respectively), suggesting that both working conditions and well-being worsened within the social care and social work workforce across the pandemic. Furthermore, each of career satisfaction, working conditions, control, general well-being and home–work interface predicted poorer well-being at Time 3. Whilst chronically poor working conditions can lead to poorer individual psychological and physiological health outcomes, our findings highlight continually poor conditions in this sector, with potential further impacts on organisations and the service users that social care workers support. It is therefore important that individuals, organisations and government develop mechanisms to support these critical workers during and following the pandemic
Self-reported experiences of midwives working in the UK across three phases during COVID-19: a cross-sectional study
Maternity services cannot be postponed due to the nature of this service, however, the pandemic resulted in wide-ranging and significant changes to working practices and services. This paper aims to describe UK midwives’ experiences of working during the COVID-19 pandemic. This study forms part of a larger multiple phase research project using a cross-sectional design based on an online survey. The online survey used validated psychometric tools to measure work-related quality of life, wellbeing, coping, and burnout as well as open-ended questions to further understand the experiences of staff working during the pandemic. This paper reports the qualitative data collected from the open-ended questions. The qualitative data were subjected to thematic analysis and the four main themes that emerged were ‘relentless stress/pressure’, ‘reconfiguration of services’, ‘protection of self and others’, and ‘workforce challenges’. The key conclusions were that midwives experienced a reduction in quality of working life and significant stress throughout the pandemic due to a range of factors including staffing shortages, restrictions placed on women’s partners, changes to services and management support, all of which compounded workforce pressures that existed prior to the pandemic. This research recommends consultation of front-line midwives in relation to possible changes in practice and workforce planning in preparation for crises such as a pandemic and to ensure equitable and supportive management with access to practical and psychological suppor
Comparing psychological wellbeing and work-related quality of life between professional groups within health and social care during the COVID-19 pandemic in the UK
This paper shared the compared results on the psychological wellbeing and work-related quality of life amongst health and social care workers during the COVID-19 pandemic in the UK. Health and social care professionals within nursing, midwifery, allied health professions, social care and social work occupations working in the United Kingdom (UK) during the pandemic were recruited. Repeated cross-sectional online surveys were conducted during two time periods of the pandemic (May–July 2020 and May−July 2021). A total of 4803 respondents completed the survey. The findings revealed that over the pandemic, psychological wellbeing (SWEWBS measure) and work-related quality of life (WRQoL scale) scores significantly decreased in all five occupations (p < 0.001) with midwives having the lowest scores on both scales at all time points. Respondents were found to significantly (p < 0.001) use of negative coping strategies such as behavioural disengagement and substance usage. Analysis of variance revealed a statistical difference between occupations and wellbeing across 2020 and 2021, while work-related quality of life was only statistically significantly different in 2021. The findings revealed that due to this decrease, there is a distinct need for more support services and flexible working conditions within health and social care services, to improve wellbeing and work-related quality of life
A cross-sectional examination of the mental wellbeing, coping and quality of working life in health and social care workers in the UK at two time points of the COVID-19 pandemic
As the COVID-19 pandemic continues to evolve around the world, it is important to examine its effect on societies and individuals, including health and social care (HSC) professionals. The aim of this study was to compare cross-sectional data collected from HSC staff in the UK at two time points during the COVID-19 pandemic: Phase 1 (May–July 2020) and Phase 2 (November 2020–January 2021). The HSC staff surveyed consisted of nurses, midwives, allied health professionals, social care workers and social workers from across the UK (England, Wales, Scotland, Northern Ireland). Multiple regressions were used to examine the effects of different coping strategies and demographic and work-related variables on participants’ wellbeing and quality of working life to see how and if the predictors changed over time. An additional multiple regression was used to directly examine the effects of time (Phase 1 vs. Phase 2) on the outcome variables. Findings suggested that both wellbeing and quality of working life deteriorated from Phase 1 to Phase 2. The results have the potential to inform interventions for HSC staff during future waves of the COVID-19 pandemic, other infectious outbreaks or even other circumstances putting long-term pressures on HSC systems
Virtual Reflexes
Virtual Reality is used successfully to treat people for regular phobias. A
new challenge is to develop Virtual Reality Exposure Training for social
skills. Virtual actors in such systems have to show appropriate social behavior
including emotions, gaze, and keeping distance. The behavior must be realistic
and real-time. Current approaches consist of four steps: 1) trainee social
signal detection, 2) cognitive-affective interpretation, 3) determination of
the appropriate bodily responses, and 4) actuation. The "cognitive" detour of
such approaches does not match the directness of human bodily reflexes and
causes unrealistic responses and delay. Instead, we propose virtual reflexes as
concurrent sensory-motor processes to control virtual actors. Here we present a
virtual reflexes architecture, explain how emotion and cognitive modulation are
embedded, detail its workings, and give an example description of an aggression
training application
Changing responses during the COVID-19 pandemic: a comparison of psychological wellbeing and work-related quality of life of UK health and social care workers
Aim: to explore the psychological wellbeing and work-related quality of life amongst United Kingdom (UK) health and social care workers during the COVID-19 pandemic. Subject and methods: Health and social care professionals within nursing, midwifery, allied health professions, social care and social work occupations working in the UK during the pandemic were recruited. Repeated cross-sectional online surveys were conducted during six time periods of the pandemic (May–July 2020, November–February 2021, May–July 2021, November 2021–February 2022, May–July 2022 and November 2022–February 2023). Results: Over 14,000 participants completed the surveys during the data collection periods. The findings revealed that over the pandemic, psychological wellbeing and work-related quality of life scores significantly decreased. Conclusions: The overall psychological wellbeing and work-related quality of life of health and social care workers during the COVID-19 pandemic significantly declined. Further research is warranted on the lasting impact of the pandemic on this workforce. The health and social care workforce needs support to prevent further deterioration and to rebuild its wellbeing and resilience
Mass spectra of doubly heavy Omega_QQ' baryons
We evaluate the masses of baryons composed of two heavy quarks and a strange
quark with account for spin-dependent splittings in the framework of potential
model with the KKO potential motivated by QCD with a three-loop beta-function
for the effective charge consistent with both the perturbative limit at short
distances and linear confinement term at long distances between the quarks. The
factorization of dynamics is supposed and explored in the nonrelativistic
Schroedinger equation for the motion in the system of two heavy quarks
constituting the doubly heavy diquark and the strange quark interaction with
the diquark. The limits of approach, its justification and uncertainties are
discussed. Excited quasistable states are classified by the quantum numbers of
heavy diquark composed by the heavy quarks of the same flavor.Comment: 14 pages, revtex4-file, 3 eps-figures, 5 tables, typos correcte
Search for R-Parity Violating Decays of Scalar Fermions at LEP
A search for pair-produced scalar fermions under the assumption that R-parity
is not conserved has been performed using data collected with the OPAL detector
at LEP. The data samples analysed correspond to an integrated luminosity of
about 610 pb-1 collected at centre-of-mass energies of sqrt(s) 189-209 GeV. An
important consequence of R-parity violation is that the lightest supersymmetric
particle is expected to be unstable. Searches of R-parity violating decays of
charged sleptons, sneutrinos and squarks have been performed under the
assumptions that the lightest supersymmetric particle decays promptly and that
only one of the R-parity violating couplings is dominant for each of the decay
modes considered. Such processes would yield final states consisting of
leptons, jets, or both with or without missing energy. No significant
single-like excess of events has been observed with respect to the Standard
Model expectations. Limits on the production cross- section of scalar fermions
in R-parity violating scenarios are obtained. Constraints on the supersymmetric
particle masses are also presented in an R-parity violating framework analogous
to the Constrained Minimal Supersymmetric Standard Model.Comment: 51 pages, 24 figures, Submitted to Eur. Phys. J.
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