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Oscillation probabilities for a PT-symmetric non-Hermitian system
No full textThere is growing interest in viable quantum theories with PT-symmetric non-Hermitian Hamiltonians, but a formulation of transition matrix elements consistent with positivity and perturbative unitarity has so far proved elusive. This Letter provides such a formulation, which relies crucially on the ability to span the state space in such a way that the interaction and energy eigenstates are orthonormal with respect to the same positive-definite inner product. We apply this non-Hermitian approach to two-neutrino flavour oscillations, and show how it can accommodate the seesaw mechanism
Lifestyle behaviours can mediate socio-economic and sex inequalities in children’s oral health:findings from Children’s Dental Health Survey 2013, England, Wales, and Northern Ireland.
Get PDFBackgroundOral health inequalities in adults are well documented but understudied in children. AimTo investigate oral health inequality amongst children within the United Kingdom (UK) by sex and socio-economic status (SES), and whether such inequality may be mediated by healthy lifestyle. DesignSecondary analysis of the Children's Dental Health Survey 2013 data for England, Wales, and Northern Ireland, including questionnaire responses on demographics, lifestyle, and clinically examined oral health measures in children aged 5, 8, 12, and 15 years in the UK. Descriptive statistics on the oral health inequalities and mediation analyses were performed, assessing lifestyle factors (regular dental attendance, sugary drink intake, and toothbrushing frequency) that potentially mediate sex and SES inequalities in oral health. ResultsA total of 9,866 children were included in this study. Oral health inequalities were observed by sex and SES amongst all aspects of oral health (dental caries, oral health-related quality of life, self-reported oral health, gingival status, and basic periodontal examination). Compared with males (35.8%), fewer females (24.1%, p < 0.001) had self-reported good dental health. Children from lower SES groups had more dental caries experience, i.e., decayed, missing, and filled teeth (DMFT), than those from middle and higher SES groups (1.0 ± 2.0 in lower vs. 0.8 ± 1.9 in middle vs. 0.4 ± 1.3 in higher, p = 0.027). Furthermore, there was evidence of lifestyle factors mediating the associations between sex, SES, and adolescents’ oral health at 12 and 15 years. ConclusionInequality was observed for children’s oral health by sex and SES; however, regular dental attendance, having less sugary drink intake and optimal toothbrushing mediated these associations in adolescents.</p
The relationship between food insecurity and tobacco or alcohol use in Great Britain:A representative population-based survey
Get PDFIntroductionTobacco and alcohol use are linked to health disparities. In recent years, food insecurity, an indicator of disparities, has increased in Great Britain. This study examined the associations between food insecurity and tobacco or alcohol use. MethodsData were drawn from a representative cross-sectional study of people aged ≥16 years in Great Britain (N = 4,056), conducted in January‒February 2025. Food insecurity was measured with the 6-item Household Food Security Scale, divided into high/marginal, low, or very low food security. Logistic regression models with food insecurity (combining low and very low food insecurity) as the outcome and adjusted for age, gender, nation of residence, socioeconomic position, financial hardship and smoking or alcohol consumption (measured using AUDIT-C score), were used to derive odds ratios (ORadj). ResultsOverall, 7.9 % (95 % CI: 6.9, 8.9) reported low and 9.6 % (8.6, 10.7) very low food security. Smoking was associated with food insecurity (ORadj = 1.75; 95 % CI: 1.32, 2.31). People who abstained from alcohol were more likely to be food insecure compared with those who drank at increasing (AUDIT-C 5: ORadj = 0.62; 0.41, 0.93) or higher risks of harm (AUDIT-C 8: ORadj = 0.63; 0.40, 0.97); however, this relationship was moderated by psychological distress. ConclusionFood insecurity was associated with higher smoking prevalence. Among people experiencing distress, those abstaining from alcohol and at risk of dependence appeared more likely to experience food insecurity than those drinking at other levels. These findings suggest the need for interventions that offer support for smoking, alcohol and which address underlying stressors of food insecurity.</p
Muscle sparing through differential nutritional control of three muscle growth mechanisms:how zebrafish larvae deal with starvation
Get PDFHow vertebrate skeletal muscle size is regulated and balanced with body size over the life-course is unclear, but is important for human health and quality of life. Muscle growth occurs by increase in myofibre number (hyperplasia) and enlargement of existing fibres (hypertrophy). Fibre enlargement reflects either hypernucleation, an increase in myofibre nuclei, and/or hyperoidy, an increase in nuclear domain size (NDS), the volume of myofibre per myonucleus. Quantitative time lapse imaging of muscle cellularity indicates that myotome growth in early larval zebrafish is dominated by hyperoidy, with lesser contribution by hypernucleation. Addition of small new myofibres makes a quantitatively even smaller contribution to growth. During neonatal mouse muscle growth a distinct balance of different growth mechanisms occurs, but yields quantitively similar hyperoidy. In zebrafish, the number of myofibres and myonuclei continue to increase in the absence of independent feeding, whereas NDS shrinks and whole body growth falters without adequate food intake from 5 days post-fertilisation, despite the continued availability of yolk. The persistent accrual of myonuclei while fibres undergo atrophy in response to starvation we term muscle sparing. Myofibre volume increases more than myofibril content during growth. During atrophy, in contrast, cytoplasmic puncta containing sarcolemmal markers become associated with autophagosomes, and lysosomes and myofibrils fill a larger fraction of the remaining sarcoplasm. These observations lead us to propose a ‘shopping bag’ hypothesis for myofibre hyperoidy and atrophy, whereby change in sarcolemmal area and myofibre volume (the ‘bag’) precede, and may be required for, changes in the myofibril content (the ‘shopping’). The distinct regulation of three muscle growth mechanisms in developing vertebrate models predict similar controls on human muscle growth which, given the importance of skeletal muscle for whole body metabolic health, are of potential relevance to the developmental origins of human health and disease
Mesh generation of curvilinear polygons for the high-order virtual element method (VEM)
Get PDFWe present a proof-of-concept methodology for generating curvilinear polygonal meshes suitable for high-order discretisations by the Virtual Element Method (VEM). A VEM discretisation requires the definition of a set of boundary and internal points used to define basis functions and compute integrals of polynomials. The procedure to locate these points on the boundary borrows ideas from previous work on a posteriori high-order mesh generation in which the geometrical inquiries to a B-rep model of the computational domain are performed via an interface to CAD libraries. Here we describe the steps of the procedure that transforms a straight-sided polygonal mesh, generated using third-party software, into a curvilinear boundary-conforming mesh. We discuss criteria for ensuring and verifying the validity of the mesh. Using an elliptic partial differential equation with Dirichlet boundary conditions as a model problem, we show that VEM discretisations on such meshes achieve the expected rates of convergence as the mesh resolution is increased. This is followed by an illustrative application of the method to the generation of a curvilinear polygonal mesh for an aerofoil geometry. We discuss polygonal curvilinear mesh quality and its enhancement, and use the motion of a cell vertex to appraise three elemental quality metrics, namely convexity, regularity and isotropy, and highlight some of the difficulties associated in their use for mesh quality optimisation. A derivative-free optimisation method is utilised to enhance curvilinear polygonal meshes by maximising a suitable measure of mesh quality. We propose such measure as a combination of the three quality metrics and apply it to optimise a distorted initial mesh for a ring geometry. We show that a suitable version of the convexity metric is effective in untangling invalid meshes. The VEM solution of a model elliptic equation is obtained for a ring geometry where a distorted and an optimised mesh show low errors, indicating that the VEM is robust and relatively insensitive to mesh distortion, and a reduction of the error in the optimised mesh. Finally, we use a more complex geometry, a computational domain for an aerofoil, as a benchmark to further illustrate the ability of the convexity metric to untangle meshes, and also to assess the suitability of two quality measures as optimisation targets to improve the overall quality of curvilinear polygonal meshes.</p
Emotion Regulation in the Association Between Posttraumatic Stress Disorder and Substance Use:A Systematic Review With Narrative Synthesis
Get PDFPosttraumatic stress disorder (PTSD) and substance use commonly co-occur and represent a unique clinical challenge. Current interventions show modest effect sizes and high rates of dropout highlighting the need to better understand the mechanisms underlying the PTSD-substance use association. Evidence suggests emotion regulation may be an important factor underlying this association. This systematic review aims to examine the role of emotion regulation in the association between PTSD and substance use and to provide an understanding of differences in emotion regulation based on gender, trauma type, and social factors. Systematic searches of Medline, Embase, PsycInfo, ASSIA, CINAHL, and Web of Science identified 33 studies that met the review inclusion criteria. While findings were mixed, the results largely suggest difficulties regulating negative and positive emotions are important in the PTSD-substance use association. Emotion regulation was elevated in individuals with PTSD-substance use disorder (SUD) compared to SUD only and among individuals with more severe PTSD and substance use symptoms. A small number of studies highlighted the role of emotion regulation difficulties over time and in relation to treatment outcomes. Preliminary findings suggested there may be differences in emotion regulation in PTSD-substance use based on gender, trauma type, and social factors, though this requires further examination. Limitations of the included studies include small sample sizes, cross-sectional designs, and a predominant focus on alcohol use. The findings largely support self-medication and negative reinforcement models of substance use and highlight the possible utility of integrated interventions focusing on emotion regulation for PTSD-substance use. Recommendations for further research are discussed.<p/
Prevalence and Geographical Distribution of Patients With Congenital Myasthenic Syndromes in the United Kingdom
Get PDFINTRODUCTION/AIMS: Congenital myasthenic syndromes (CMS) are often underdiagnosed due to phenotypic overlap with other neuromuscular disorders. Limited epidemiological data and low awareness hinder early diagnosis, which is key for effective treatment. Early recognition of CMS is important as symptomatic treatments often specific for genetic subtypes exist and emerging therapies are in the pipeline. This study aims to estimate the prevalence of genetically confirmed CMS in the United Kingdom and explore geographical variations.METHODS: Prevalence was calculated as of 31 December 2023, including genetically confirmed CMS patients residing in the United Kingdom and known to be alive. Patients with missing geographic or living status data were excluded. Prevalence was estimated overall and compared between UK regions served by a highly specialized neuromuscular service (hsNMS) and those without such services (non-hsNMS).RESULTS: A cohort of 442 genetically confirmed CMS patients was identified. CHRNE deficiency, DOK7, RAPSN were the most common subtypes. The UK prevalence was 6.5 cases per million overall and 8.5 cases per million in the pediatric population. The overall prevalence was statistically higher in hsNMS (8.8 cases per million) compared to non-hsNMS regions (5.9 cases per million). Homozygous patients had a more clustered distribution particularly around urban area.DISCUSSION: Our results suggest there is likely underdiagnosis of CMS in many areas of the United Kingdom and hsNMS may play an important diagnostic role. Variations may also be related to other cultural clustering and founder effects. Further research should explore how healthcare access, ethnicity, and consanguinity contribute to regional variation and diagnostic rates.</p
‘That Grammar grudge not our English tong’. Linguistic nationalism in early modern England and the discursive shift from apologia to assertion
Get PDFEarly modern humanism brought about profound psychological shifts in the perception of vernacular languages, which increasingly became important symbols of emerging national identities. Yet Europe’s languages were not equal. In England–newly isolated from the continent both politically and diplomatically–the imposition of English as the language of state and church aimed to consolidate insular unity and cultural identity, despite it lacking the international prestige it holds today. This paper argues that the enduring characterisation of ‘good’ English as ‘plain’ and ‘manly’ Germanic11 Following the advice of an anonymous reviewer, I have deliberately avoided using the term ‘Anglo-Saxon’ in this paper (except where directly quoting others) because of the potentially negative connotations it may carry for some readers. While my intention was to critique the nationalist discourse behind the concept of Anglo-Saxonism, I acknowledge that use of the term might inadvertently reinforce the very concept I aim to problematise. See Rambaran-Olm and Wade’s (2022) discussion and visceral critique of the term. As a British scholar, I am keen to avoid the complacency identified by these authors, who are critical of UK medievalists who frame the ‘racial use’ of the term as an American problem. Instead, I have used ‘Germanic’ as a linguistic category and ‘pre-Conquest’ to designate the historical period. English originates in this period of assertive linguistic nationalism. English began consciously to distinguish itself from the ‘flowery’, Latinate languages, including the ‘smooth-tong’d French’ (Tomkis 1607, 19) whose influence was increasingly derided in satire as insincere and pompous. After establishing the historical context, I examine key advocates for English from the 16th century who, aware of its mixed linguistic roots, celebrated a purer, proudly monosyllabic English stripped of rhetorical artifice and the perceived duplicity of ‘inkhorn’ terms and foreign borrowings. This marked a decisive turn from defending the use of English on the grounds of its practical value as the common tongue towards its promotion as a legitimate and distinctively national literary language.</p
Fungal infection drives metabolic reprogramming in epithelial cells via aerobic glycolysis and an alternative TCA cycle shunt
No full textCandida albicans–induced immunometabolic changes drive complex responses in immune cells. However, whether and how C. albicans causes remodeling of oral epithelial cell (OEC) metabolism is unclear. Here, we use in vitro experiments and patient biopsies to demonstrate that OECs undergo metabolic reprogramming when infected by C. albicans independently of candidalysin secretion, increasing glycolysis and decreasing tricarboxylic acid (TCA) cycle activity. Glycolysis and glucose transport inhibition show that these pathways support OEC cytokine release, highlighting the partial control of antifungal epithelial immunity by cellular metabolism. However, glucose supplementation disrupts OEC responses both in vitro and in vivo, suggesting that the fungus benefits from these metabolic shifts and that increased aerobic glycolysis in OECs is detrimental. Genome-scale metabolic modeling predicted a shutdown of the TCA cycle and a previously unidentified role for glutamic-oxaloacetic transaminase 1 (GOT1) in response to C. albicans, which was subsequently shown to be important for OEC survival during infection. This study reveals a fundamental role for hexose metabolism and identifies a GOT1-mediated TCA cycle shunt in regulating OEC survival and immune responses during mucosal fungal infections.</p
Preventable deaths related to haemorrhage in England and Wales, 2013–2022:A systematic case series of coroners’ reports
Get PDFObjectivesTo identify preventable haemorrhage-related deaths, classify coroner concerns and explore organisational responses.Study designRetrospective systematic case series of coroners’ Prevention of Future Deaths (PFD) reports from 1st July 2013 to 16 November 2022, in England and Wales.MethodsReports were acquired from the Courts and Tribunals Judiciary website and screened for haemorrhage-related deaths using a reproducible automated computer code. Demographic information, coroners’ concerns, and organisational responses to PFDs were extracted and analysed, including risk factors predisposing to haemorrhage.Results339 PFDs (8 % of all PFDs) involved a haemorrhage event contributing to death. The average age of death was 78 years, and 57 % were male. The majority of haemorrhages were intracranial (64 %). 31 % of haemorrhage-related PFDs reported the use of anticoagulation, most often warfarin. Coroners reported 942 concerns directly relevant to the haemorrhage event, including failures to follow protocols, guidelines, or risk assessments (17 %), failures in communication or handovers (14 %), and failures in providing appropriate care, including investigations and observations (13 %). Just under half (48 %) of PFDs did not have responses published on the Judiciary website. Of the organisations who responded, 85 % reported plans to initiate new changes to address these concerns. Improvements most frequently focused on improving protocols, pathways and guidance documents, as well as education and training.ConclusionsCoroner PFDs offer unique insights into haemorrhage-related deaths, highlighting the systems and processes which fail in everyday practice. Improving awareness and dissemination of these reports to clinicians and policymakers nationally may improve patient safety and save lives.<p/