• Dynamics of Shadow System of a Singular Gierer–Meinhardt System on an Evolving Domain

      Kavallaris, Nikos I.; orcid: 0000-0002-9743-8636; email: n.kavallaris@chester.ac.uk; Barreira, Raquel; Madzvamuse, Anotida; orcid: 0000-0002-9511-8903 (Springer US, 2020-12-18)
      Abstract: The main purpose of the current paper is to contribute towards the comprehension of the dynamics of the shadow system of a singular Gierer–Meinhardt model on an isotropically evolving domain. In the case where the inhibitor’s response to the activator’s growth is rather weak, then the shadow system of the Gierer–Meinhardt model is reduced to a single though non-local equation whose dynamics is thoroughly investigated throughout the manuscript. The main focus is on the derivation of blow-up results for this non-local equation, which can be interpreted as instability patterns of the shadow system. In particular, a diffusion-driven instability (DDI), or Turing instability, in the neighbourhood of a constant stationary solution, which then is destabilised via diffusion-driven blow-up, is observed. The latter indicates the formation of some unstable patterns, whilst some stability results of global-in-time solutions towards non-constant steady states guarantee the occurrence of some stable patterns. Most of the theoretical results are verified numerically, whilst the numerical approach is also used to exhibit the dynamics of the shadow system when analytical methods fail.
    • Quantifying the impact of tissue metabolism on solute transport in feto-placental microvascular networks

      Erlich, Alexander; orcid: 0000-0002-2294-1894; Nye, Gareth A.; orcid: 0000-0003-4508-0406; Brownbill, Paul; orcid: 0000-0002-8328-7072; Jensen, Oliver E.; orcid: 0000-0003-0172-6578; Chernyavsky, Igor L.; orcid: 0000-0003-0284-9318 (The Royal Society, 2019-08-16)
      The primary exchange units in the human placenta are terminal villi, in which fetal capillary networks are surrounded by a thin layer of villous tissue, separating fetal from maternal blood. To understand how the complex spatial structure of villi influences their function, we use an image-based theoretical model to study the effect of tissue metabolism on the transport of solutes from maternal blood into the fetal circulation. For solute that is taken up under first-order kinetics, we show that the transition between flow-limited and diffusion-limited transport depends on two new dimensionless parameters defined in terms of key geometric quantities, with strong solute uptake promoting flow-limited transport conditions. We present a simple algebraic approximation for solute uptake rate as a function of flow conditions, metabolic rate and villous geometry. For oxygen, accounting for nonlinear kinetics using physiological parameter values, our model predicts that villous metabolism does not significantly impact oxygen transfer to fetal blood, although the partitioning of fluxes between the villous tissue and the capillary network depends strongly on the flow regime.
    • In vitro and computational modelling of drug delivery across the outer blood–retinal barrier

      Davies, Alys E.; orcid: 0000-0002-3489-0182; Williams, Rachel L.; Lugano, Gaia; Pop, Serban R.; Kearns, Victoria R.; orcid: 0000-0003-1426-6048 (The Royal Society, 2020-02-14)
      The ability to produce rapid, cost-effective and human-relevant data has the potential to accelerate the development of new drug delivery systems. Intraocular drug delivery is an area undergoing rapid expansion, due to the increase in sight-threatening diseases linked to increasing age and lifestyle factors. The outer blood–retinal barrier (OBRB) is important in this area of drug delivery, as it separates the eye from the systemic blood flow. This study reports the development of complementary in vitro and in silico models to study drug transport from silicone oil across the OBRB. Monolayer cultures of a human retinal pigmented epithelium cell line, ARPE-19, were added to chambers and exposed to a controlled flow to simulate drug clearance across the OBRB. Movement of dextran molecules and release of ibuprofen from silicone oil in this model were measured. Corresponding simulations were developed using COMSOL Multiphysics computational fluid dynamics software and validated using independent in vitro datasets. Computational simulations were able to predict dextran movement and ibuprofen release, with all of the features of the experimental release profiles being observed in the simulated data. Simulated values for peak concentrations of permeated dextran and ibuprofen released from silicone oil were within 18% of the in vitro results. This model could be used as a predictive tool for drug transport across this important tissue.
    • The challenge of hospitality: marking remembrance as an Anglican in a multifaith parish

      Lees-Smith, Anthony; orcid: 0000-0002-4322-3998 (Informa UK Limited, 2021-02-14)
    • Event-related and readiness potentials when preparing to approach and avoid alcohol cues following cue avoidance training in heavy drinkers

      Di Lemma, Lisa C. G.; email: l.dilemma@chester.ac.uk; Stancak, Andrej; Soto, Vicente; Fallon, Nick; Field, Matt (Springer Berlin Heidelberg, 2020-02-26)
      Abstract: Rationale: Cue avoidance training (CAT) reduces alcohol consumption in the laboratory. However, the neural mechanisms that underlie the effects of this intervention are poorly understood. Objectives: The present study investigated the effects of a single session of CAT on event-related and readiness potentials during preparation of approach and avoidance movements to alcohol cues. Methods: Heavy drinking young adults (N = 60) were randomly assigned to complete either CAT or control training. After training, we recorded participants’ event-related and motor readiness potentials as they were preparing to respond. Results: In the CAT group, N200 amplitude was higher when preparing to approach rather than avoid alcohol pictures. In the control group, N200 amplitudes did not differ for approach and avoidance to alcohol pictures. Regarding the late positive potential (LPP), in the CAT group, the negativity of this was blunted when preparing to avoid alcohol pictures relative to when preparing to avoid control pictures. In the control group, the negativity of the LPP was blunted when preparing to approach alcohol pictures relative to when preparing to approach control pictures. There were no effects on motor readiness potentials. Behavioural effects indicated short-lived effects of training on reaction times during the training block that did not persist when participants were given time to prepare their motor response before executing it during the EEG testing block. Conclusions: After a single session of CAT, the enhanced N200 when approaching alcohol cues may indicate the engagement of executive control to overcome the associations learned during training. These findings clarify the neural mechanisms that may underlie the effects of CAT on drinking behaviour.
    • The Scarecrow Christ

      Middleton, Paul (Amsterdam University Press, 2020-01-31)
      Paul Middleton deals with the contested homosexual martyr Matthew Shepard. Matthew Shepard, a gay twenty-one year old political science student at the University of Wyoming, was robbed and brutally beaten by two other men on the night of Tuesday, 6 October 1998. The men tied him to a fence after the attack, while he was bleeding profusely in freezing temperatures. He died a few days later, on 12 October 1998, and was called a martyr in Time Magazine, just a week after his death. Middleton examines the popular martyr-making process in respect of Matthew Shepard, arguing that both the making of the martyr and the reaction it provoked reflect American ‘culture wars’, because martyrology is conflict literature, foremost about the conflict between the story-tellers and their opponents. Ironically, both LGBT activists and right-wing religious groups have in some ways sought to undermine Shepard’s martyr status by focusing on his life rather than his death. Such efforts, as Middleton argues, had a limited effect because in martyrologies any interest in the lives of their heroes is incidental, merely setting up the scene for a significant death.
    • Michael Gilmour, Animals in the Writings of C.S. Lewis

      Clough, David (Edinburgh University Press, 2019-10)

      Graham, Elaine (Liverpool University Press, 2020-01)
    • Limb preference and personality in donkeys (Equus asinus)

      Díaz, Sergio; orcid: 0000-0002-3070-0097; Murray, Lindsay; orcid: 0000-0002-7810-9546; Rodway, Paul; orcid: 0000-0002-7667-6782 (Informa UK Limited, 2021-02-05)
    • Two high-order time discretization schemes for subdiffusion problems with nonsmooth data

      Wang, Yanyong; Yan, Yubin; Yang, Yan (Walter de Gruyter GmbH, 2020-11-13)
      Abstract Two new high-order time discretization schemes for solving subdiffusion problems with nonsmooth data are developed based on the corrections of the existing time discretization schemes in literature. Without the corrections, the schemes have only a first order of accuracy for both smooth and nonsmooth data. After correcting some starting steps and some weights of the schemes, the optimal convergence orders O(k 3–α ) and O(k 4–α ) with 0 < α < 1 can be restored for any fixed time t for both smooth and nonsmooth data, respectively. The error estimates for these two new high-order schemes are proved by using Laplace transform method for both homogeneous and inhomogeneous problem. Numerical examples are given to show that the numerical results are consistent with the theoretical results.
    • The Gravitational Pull of Identity: Professional Growth in Sport, Exercise, and Performance Psychologists

      Tod, David; orcid: 0000-0003-1084-6686; McEwan, Hayley; orcid: 0000-0001-5316-8446; Chandler, Charlotte; orcid: 0000-0003-3324-8259; Eubank, Martin; orcid: 0000-0002-9696-0537; Lafferty, Moira; orcid: 0000-0002-3877-5800 (Informa UK Limited, 2020-10-07)
    • Popular geopolitics ‘beyond the screen’: Bringing Modern Warfare to the city

      Bos, Daniel (SAGE Publications, 2020-07-16)
      Popular culture – in this case military-themed videogames – has been argued to mould and shape popular understandings of the geopolitics of the ‘war on terror’. To date, most attention has been focused on the geopolitical representations of a ‘final’ popular cultural text or object. Less attention has been paid to how popular understandings of geopolitics and military violence have been constructed and commodified prior to, and ‘beyond the screen’. Empirically, the paper examines the marketing campaign of Call of Duty: Modern Warfare 3. Through the use of experiential marketing, I show how the game’s launch night incorporated spectacular displays, performances and consumer interactions to sell the pleasures of virtual war by drawing on geopolitical fears of terrorism and military violence within major Western cities. Firstly, I demonstrate how marketing engaged with and transformed urban spaces extending the popular geopolitics of virtual war. Secondly, the paper reveals how experiential marketing targeted and encouraged connections with and between attendees’ bodies. Thirdly, I demonstrate how such events promote geopolitical encounters which extend beyond the temporal and the spatial confines of the marketing event itself. Ultimately, the paper reveals how urban fears surrounding the global ‘war on terror’ were employed to sell the pleasures and geopolitics of virtual war.
    • Examining the Relationship Between Autism Traits and Sleep Duration as Predictors of Suicidality

      Hochard, K. D.; orcid: 0000-0001-9611-4683; email: k.hochard@chester.ac.uk; Pendrous, R.; Mari, T.; Flynn, S. (Springer US, 2020-02-21)
      Abstract: Short sleep duration is a known risk factor for suicidality in the general population, yet it is unclear how short sleep interacts with autism traits in predicting suicidality. In this cross-sectional online study, a general population sample (N = 650) completed measures assessing autism traits, suicidal ideation, and sleep duration. Moderated hierarchical regressions demonstrated that higher autism traits and shorter sleep were independent predictors of increased suicide ideation. However, sleep duration did not significantly moderate the autism trait to suicide ideation relationship. Future work should explore this relationship longitudinally using objective measures before considering intervention work to increase sleep duration in those with elevated autism traits.
    • Evaluating serious stress in military veterans, their carers and families: a protocol.

      Finnegan, Alan; orcid: 0000-0002-2189-4926; email: a.finnegan@chester.ac.uk; Di Lemma, L; Mcghee, S; orcid: 0000-0002-2006-8403; Watson, R (2021-02-05)
      In 2018, the Armed Forces Covenant Fund Trust (ACFT) allocated approximately £4M to seven UK projects to address serious stress in military veterans, their carers and families. These programmes commenced between May and October 2019 and will conclude in August 2021.This paper outlines the protocol for the evaluation of the Serious Stress programme and the novel support provided to grant holders. Entry into the programmes was through multiple routes, including self-referrals with an anticipated sample of approximately 2000 participants. A common outcomes framework was designed to measure outcomes. Grant holders accepted ownership for data collection and quality and were supported through accompanying guidance material.Veterans were often reluctant to seek support, and the anonymous and confidential nature of the evaluation plus the study team's military background helped address this. Participants' voices were a key part in developing the protocol, leading to results to inform policy and highlight success, efficiency and cost effectiveness, and providing markers for future development.The study provided a reservoir of information. Interim reports indicated compliance with performance indicators and provided timely evidence. Shared learning provided grant holders with an indication of what was helping the beneficiaries and what needed to be improved. The combination of all data sets provided the ACFT with a resource to demonstrate success and insight into projects where improvement was required, and indicators of how to redress these problems. The study protocol provided a platform for building lasting partnerships. [Abstract copyright: © Author(s) (or their employer(s)) 2021. No commercial re-use. See rights and permissions. Published by BMJ.]
    • Limb preference and personality in donkeys (

      Díaz, Sergio; orcid: 0000-0002-3070-0097; Murray, Lindsay; orcid: 0000-0002-7810-9546; Rodway, Paul; orcid: 0000-0002-7667-6782 (2021-02-05)
      Interhemispheric laterality has often been linked to different behavioural styles. This study investigates the link between limb preference and personality in donkeys. The sample consisted of 47 donkeys ( ), 30 males and 17 females. Limb preference was determined using observation of the leading limb in a motionless posture and personality was measured using the Donkey Temperament Questionnaire (French, J. M. (1993). Assessment of donkey temperament and the influence of home environment. , (2), 249-257. doi:10.1016/0168-1591(93)90014-G) completed by the donkeys' keepers. A Principal Component Analysis obtained two components: Agreeableness and Extraversion. Age showed a positive relationship with Agreeableness, echoing trends in humans Donkeys did not show a population-level preference towards either side. Limb preference significantly predicted the trait : donkeys with a preference to keep the right foot forward when motionless were harder to handle. This study presents the first investigation into limb preference and personality in donkeys, although more research is needed to clarify whether there is a population-level limb preference bias in donkeys, and the relationship between limb preference and Agreeableness.
    • Do stress and anxiety in early pregnancy affect the progress of labor: Evidence from the Wirral Child Health and Development Study.

      Slade, Pauline; orcid: 0000-0001-5877-2706; Sheen, Kayleigh; Weeks, Andrew; Wray, Susan; De Pascalis, Leonardo; Lunt, Karen; Bedwell, Carol; Thompson, Belinda; Hill, Johnathan; Sharp, Helen (2021-02-05)
      Despite widespread belief that anxiety causes longer labor, evidence of association is inconsistent. Data gathered as part of a prospective epidemiological longitudinal study were used to investigate associations between antenatal anxiety and pregnancy-specific stress, and labor progression was assessed by duration and use of augmentation. Pregnant primiparous women completed measures for anxiety and pregnancy-specific stress at 20 weeks' gestation (n = 1145). Birth outcome data were extracted from medical records. Regression analyses and a path analysis assessed associations between antenatal anxiety and pregnancy-specific stress, and indices of labor progression (labor duration and augmentation). Anxiety/pregnancy-specific stress were not directly associated with duration of stage 1 labor (HIGH/LOW anxiety: mean difference = 13.94 minutes, SD = 20.66, 95% CI -26.60 to 54.49, P < .50)/(HIGH/LOW pregnancy-specific stress: mean difference = 12.05 minutes, SD = 16.09, 95% CI -19.52 to 43.63, P < .45). However, anxiety/pregnancy-specific stress were associated with epidural use (HIGH/LOW anxiety: 39% vs 31%, P < .042; HIGH/LOW pregnancy-specific stress: 38% vs 29%, P < .001), which was itself associated with longer labor (mean difference: 158.79 minutes, SD = 16.76, 95% CI 125.89-191.68, P < .001). Anxiety and pregnancy-specific stress were associated with increased likelihood of augmentation but these associations were nonsignificant after accounting for epidural, which was itself highly associated with augmentation. However, path analysis indicated an indirect effect linking pregnancy-specific stress, but not general anxiety, to labor duration and augmentation: elevated pregnancy-specific stress led to greater use of epidural, which was linked to both increased rates of augmentation, and increased labor duration. Contrary to general belief, general anxiety and specific pregnancy stress were not directly linked to longer duration of stage one labor. However specific pregnancy stress was associated with epidural use, which in turn was significantly associated with risk of augmentation, and longer stage one labor. Identification of pregnancy-specific stress could help to identify women for whom psychological interventions could improve birth experience. [Abstract copyright: © 2020 The Authors. Acta Obstetricia et Gynecologica Scandinavica published by John Wiley & Sons Ltd on behalf of Nordic Federation of Societies of Obstetrics and Gynecology (NFOG).]
    • High order algorithms for numerical solution of fractional differential equations

      Asl, Mohammad Shahbazi; email: mshahbazia@yahoo.com; Javidi, Mohammad; Yan, yubin (Springer International Publishing, 2021-02-17)
      Abstract: In this paper, two novel high order numerical algorithms are proposed for solving fractional differential equations where the fractional derivative is considered in the Caputo sense. The total domain is discretized into a set of small subdomains and then the unknown functions are approximated using the piecewise Lagrange interpolation polynomial of degree three and degree four. The detailed error analysis is presented, and it is analytically proven that the proposed algorithms are of orders 4 and 5. The stability of the algorithms is rigorously established and the stability region is also achieved. Numerical examples are provided to check the theoretical results and illustrate the efficiency and applicability of the novel algorithms.