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Mental Imagery of the Self in Body Dysmorphic Disorder: A Mixed‐Methods Systematic Review
Full text linkMental imagery has been identified as a key feature of the onset, maintenance and treatment of psychological disorders. Research on the role of mental imagery in body dysmorphic disorder (BDD), a condition hallmarked by negative sensory appraisals of the self, has been increasingly recognised in theoretical perspectives and psychological interventions. However, the scope and implications of this work have not yet been reviewed. This systematic review sought to identify the characteristics and proposed mechanisms of imagery in BDD, synthesising qualitative and quantitative data using Meta‐Integration. Quality was assessed using the Mixed Methods Appraisal Tool. Thirty‐seven studies were identified among 33 publications. Study quality was mixed with significant methodological heterogeneity. Mental imagery in BDD is consistently reported to be vivid, emotionally intense, recurrent and important in the maintenance and potentially the onset of BDD. These findings concur with theoretical frameworks of BDD (and other related conditions) which highlight the causal role of imagery and encourage the use of imagery‐based interventions. Crucial areas for future work include stronger causal tests, unpacking mechanisms, attention to individual differences and intersectionality and exploring the potential for imagery‐based approaches for innovations in treatment and prevention across the lifespan, particularly in adolescence when BDD first develops
A longitudinal quasi-experimental study of a pedagogical approach to supporting undergraduate well-being and mental health: digital interdisciplinary accredited elective mental health literacy university course
Full text linkBackground: Entry to higher education coincides with a period of accelerated psychosocial and brain development. Student need for acceptable and accessible well-being and mental health support is straining university resources. Aims: To evaluate the acceptability and impact of a digital mental health literacy course tailored for undergraduates and delivered as an accredited interdisciplinary elective. Method: Analyses included pre–post course survey data from enrolled students and longitudinal U-Flourish Well-Being Survey data from a comparison sample of non-course takers over the same period (2021–2024). Linear mixed-effects models examined associations between course participation and 12-week changes in mental health literacy, psychosocial risk factors, well-being and common mental health concerns. Results: Pre–post course survey data (N = 2884) supported high acceptability, improvements in resilience (+0.06; 95% CI 0.03–0.08, p < 0.001) and self-compassion (+0.65; 95% CI 0.46–0.84, p < 0.001), and a reduction in brooding (−0.31; 95% CI −0.44 to−0.18, p < 0.001). Taking the course was associated with a reduction in anxiety (β = −0.41; 95% CI −0.55 to −0.27, p < 0.001) and cannabis use (proportional odds ratio 0.82; 95% CI 0.75–0.90, p < 0.001), improvement in sleep quality (β = 0.79; 95% CI 0.61–0.97, p < 0.001) and evidence of a protective effect on well-being (β = 0.24; 95% CI 0.11–0.36, p < 0.001) and depressive symptoms (β = −0.37; 95% CI −0.52 to −0.21, p < 0.001), compared with non-course takers. Effects differed by gender, with women benefitting most, but were comparable across minoritised student subgroups. Conclusions: Mental health literacy delivered as an accredited undergraduate interdisciplinary course is highly acceptable and associated with improvement in psychological coping and positive effects on student mental health and well-being. Future research should focus on more diverse student samples, underlying mechanisms and sustained effects
Sub-picosecond permittivity of carbon nitrides probed with terahertz spectroscopy: revealing high dielectric response and conductivity
Full text linkOrganic based semiconductor materials offer emerging and sustainable solutions for solar energy conversion technologies and electronics. However, knowledge of their intrinsic (photo)physical properties is often limited, especially the effect of dielectric properties (εr = ε′) on exciton separation and charge generation at sub-picosecond timescales, which corresponds to THz frequencies. Thus, THz Time Domain Spectroscopy (THz-TDS) is used to directly and accurately extract the complex permittivity (ε = ε′ + iε″) and THz conductivity (σTHz) of organic Carbon Nitrides (CNx) and other polymers and elucidate the influence of environmental humidities. Overall, the THz dielectric response ε′ of CNx surpasses other organic and even glycolated materials, and water. For the ionic and 2D carbon nitride K-PHI, complex permittivity ε was observed to be strongly humidity dependent, with both ε′ and σTHz doubling from dry to humid conditions (ε′ from ∼4 to 8, σTHz 75 to 150 S/m, respectively). When compared to other photocatalysts, the THz dielectric response of CNx and especially humid K-PHI is within range of well-known oxides such as TiO2 that can efficiently generate charges from excitons, due to low exciton binding energies resulting from high ε′. The importance of dielectric property characterization on functionally relevant frequencies is thus highlighted, especially in the THz gap (0.1 – 10 THz), to understand the photophysical behaviour of organic semiconductors, even in the presence of water and hydrated ions. Such THz complex permittivity determination may also be beneficial for exploring next generation photo(electro)catalysts, electronics or ionotronics, and for computational property predictions that often require knowledge of ultrafast photophysical properties
Persistent immune, coagulation and cardiac dysregulation are correlated with later post-discharge mortality in children with severe malnutrition
Full text linkBackground: Children with complicated severe malnutrition (CSM) face high mortality after hospital discharge, yet the underlying mechanisms remain poorly understood. While early post-discharge mortality (< 2 months) has been linked to a sepsis-like inflammatory profile measured at discharge, it is unclear whether this relationship persists (later mortality; 2–6 months post-discharge). This study investigated whether immune, inflammatory, and endothelial dysfunction at 2 months post-discharge are associated with later mortality in children recovering from CSM. Methods: We conducted a case–control study nested within a randomised placebo-controlled trial of daily co-trimoxazole in HIV-negative children aged 2–59 months with CSM in four Kenyan hospitals. Cases were children who died between 2 and 6 months post-discharge; controls were survivors frequency-matched by sex, site, and trial arm. Plasma cytokines, chemokines, endothelial markers, and untargeted proteomics were measured at discharge and 2 months post-discharge. Conditional Cox regression, adjusted for age, sex, site, mid-upper arm circumference (MUAC), and randomisation arm, was used to identify biomarkers associated with later mortality. Results: Cases were younger (had a median of 7 vs. 11 months), had longer hospital stays (14 vs. 10 days), and showed lower anthropometry (MUAC = 10.7 vs. 12.0 cm) and lower haemoglobin (9.7 vs. 10.6 g/dL) at 2 months post-discharge (all p < 0.05). Mortality 2–6 months post-discharge was associated with elevated inflammatory mediators (e.g. IL-10 [hazard ratio, HR: 1.47, 95% confidence interval, CI: 1.00–2.14], IL-15 [1.65, 95% CI: 1.08–2.51], IFN-α2 [1.51, 95% CI: 1.02–2.23]), acute phase proteins, apolipoproteins and coagulation markers, including fibrinogen, histidine-rich glycoprotein (1.40, 95% CI: 1.01–1.94), protein C inhibitor (SERPINA5, 1.50, 95% CI: 1.07–2.08), SERPINA10 (1.42, 95% CI: 1.02–1.99), and ADAMTS13 (0.41, 95% CI: 0.24–0.70). Additionally, cardiovascular and muscle-related proteins such as angiotensinogen (1.46, 95% CI: 1.03–2.08), α- and β-tropomyosin (0.68, 95% CI: 0.48–0.98), PI16 (0.72, 95% CI:0.54–0.97), and zyxin (0.61, 95% CI: 0.40–0.92) were elevated in cases. Conclusions: Later mortality in children recovering from CSM is associated with persistent immune activation, a sepsis-like phenotype involving multiple systems. These findings suggest that children at risk of later mortality may benefit from biomarker-guided interventions initiated at discharge
Impact of memory on clustering in spontaneous particle aggregation
No full textThe effect of short-term and long-term memory on spontaneous aggregation of organisms is investigated using a stochastic agent-based model. Each individual modulates the amplitude of its random motion according to the perceived local density of neighbors. Memory is introduced via a chain of K internal variables that allow agents to retain information about previously encountered densities. The parameter K controls the effective length of memory. A formal mean-field limit yields a macroscopic Fokker–Planck equation, which provides a continuum description of the system in the large-population limit. Steady states of this equation are characterized to interpret the emergence and morphology of clusters. Systematic stochastic simulations in one- and two-dimensional spatial domains reveal that short- or moderate-term memory promotes coarsening, resulting in a smaller number of larger clusters, whereas long-term memory inhibits aggregation and increases the proportion of isolated individuals. Statistical analysis demonstrates that extended memory reduces the agents’ responsiveness to environmental stimuli, explaining the transition from aggregation to dispersion as K increases. These findings identify memory as a key factor controlling the collective organization of self-driven agents and provide a bridge between individual-level dynamics and emergent spatial patterns
(2+1)d lattice models and tensor networks for gapped phases with categorical symmetry
Full text linkGapped phases in 2+1 dimensional quantum field theories with fusion 2-categorical symmetries were recently classified and characterized using the Symmetry Topological Field Theory (SymTFT) approach [L. Bhardwaj et al., SciPost Phys. 19, 056 (2025); L. Bhardwaj et al., arXiv: 2502.20440]. In this paper, we provide a systematic lattice model construction for all such gapped phases. Specifically, we consider “all-boson type” fusion 2-category symmetries, all of which are obtainable from 0-form symmetry groups
G
G
(possibly with an ’t Hooft anomaly) via generalized gauging—that is, by stacking with an
H
H
-symmetric TFT and gauging a subgroup
H
H
. The continuum classification directly informs the lattice data, such as the generalized gauging that determines the symmetry category, and the data that specifies the gapped phase. We construct commuting projector Hamiltonians and ground states applicable to any non-chiral gapped phase with such symmetries. We also describe the ground states in terms of tensor networks. In light of the length of the paper, we include a self-contained summary section presenting the main results and examples
Gradient flows of ( K, N ) -convex functions with negative N: Gradient flows of ( K, N ) -convex functions..
Full text linkWe discuss (K, N)-convexity and gradient flows for (K, N)-convex functionals on metric spaces, in the case of real K and negative N. In this generality, it is necessary to consider functionals unbounded from below and/or above, possibly attaining as values both the positive and the negative infinity. We prove several properties of gradient flows of (K, N)-convex functionals characterized by Evolution Variational Inequalities, including contractivity, regularity, and uniqueness
Validating primary and secondary healthcare resource use and costs estimates in OMOP-mapped vs source CPRD-HES data in the UK
No full textWalsh mode based neural network for adaptive optics in two-photon microscopy
No full textMicroscopy is a vital tool in biomedical research. In deep tissue two-photon imaging, scattering induces severe wavefront distortions, which degrade image quality. Adaptive optics is used to restore image quality; however, conventional continuous modes are insufficient for compensating complex wavefronts. This thesis introduces neural-network–based sensorless adaptive optics methods using pixelated Walsh modes for complex wavefront compensation. These methods are designed to be robust and more efficient than conventional algorithms in improving image quality. The neural networks exploit the unique geometrical properties of Walsh modes and, in the machine-learning-assisted wavefront-sensorless adaptive optics control method (MLAO), also utilize aberration structure information extracted from extended images. Both approaches can outperform the conventional 2N+1 algorithm and the sequential 3N algorithm in efficiency for image quality improvement while maintaining robust performance under various conditions. Neural-network-based sensorless adaptive optics methods using Walsh modes show significant potential for deep biomedical imaging. Their high efficiency reduces aberration correction time and specimen exposure while maintaining high image quality, and their robust performance ensures versatility across diverse imaging conditions. These results indicate that combining Walsh modes with neural networks provides a powerful framework for advancing sensorless adaptive optics in complex wavefront compensation
The X-Ray Dot: Exotic Dust or a Late-stage Little Red Dot?
No full textJWST’s “little red dots” (LRDs) are increasingly interpreted as active galactic nuclei (AGN) obscured by dense thermalized gas rather than dust as evidenced by their X-ray weakness, blackbody-like continua, and Balmer line profiles. Key questions are how LRDs connect to standard UV-luminous AGN, whether transitional phases exist, and whether they are observable. We present the “X-ray dot” (XRD), a compact source at z = 3.28 observed by the NIRSpec Wide Guaranteed Time Observation survey. The XRD exhibits LRD hallmarks: a blackbody-like (Teff ≃ 6400 K) red continuum, a faint but blue rest-UV excess, falling mid-IR emission, and broad Balmer lines (FWHM ∼ 2700–3200 km s−1). Unlike LRDs, however, it is remarkably X-ray luminous (L2−10 keV = 1044.18 erg s−1) and has a continuum inflection that is blueward of the Balmer limit. We find that the red rest-optical and blue mid-IR continuum cannot be reproduced by standard dust-attenuated AGN models without invoking extremely steep extinction curves, nor can the weak mid-IR emission be reconciled with well-established X-ray–torus scaling relations. We therefore consider an alternative scenario: the XRD may be an LRD in transition, where the gas envelope dominates the optical continuum but optically thin sight lines allow X-rays to escape. The XRD may thus provide a physical link between LRDs and standard AGN, offering direct evidence that LRDs are powered by supermassive black holes and providing insight into their accretion properties