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Normalized solutions for a Sobolev critical fractional Schrödinger-Poisson system
No full textIn this paper, we study the existence of normalized
solutions for the fractional critical Schr\"{o}dinger-Poisson system
\begin{cases} (-\Delta)^su +\gamma \phi
u= \lambda u+\mu|u|^{q-2}u+|u|^{2^*_s-2}u,&~~ \mbox{in}~\R^3,\\
(-\Delta)^t\phi=u^2,&~~ \mbox{in}~\R^3,
\end{cases}
with the prescribed -norm where satisfies
and
are parameters. We establish several existence results for the -subcritical regime, i.e., ; the -critical regime, i.e., , and the -supercritical regime, i.e., . These cases are studied under different assumptions imposed on the parameters and the mass , respectively. To prove the above conclusions, we comprehensively apply the Jeanjean's theory, Pohozaev manifold method and
Brezis-Nirenberg's technique skill to overcome the lack of
compactness. This paper complements the paper by
He, Meng and Squassina (Calc.\ Var.\ PDE.\ \textbf{63} (2024), No. 6, paper 142); and the paper by Li and Teng (Mediterr.\ J.\ Math.\ \textbf{20} (2023), No. 2, paper 92), since we consider the normalized solutions of the fractional Schr\"{o}dinger-Poisson problems with the Sobolev critical term, and the perturbation
is allowed to have -critical growth, i.e., .</p
Multiprobe cosmology from the abundance of SPT clusters and des galaxy clustering and weak lensing
No full textCosmic shear, galaxy clustering, and the abundance of massive halos each probe the large-scale structure of the Universe in complementary ways. We present cosmological constraints from the joint analysis of the three probes, building on the latest analyses of the lensing-informed abundance of clusters identified by the South Pole Telescope (SPT) and of the auto- and cross-correlation of galaxy position and weak lensing measurements (3×2pt) in the Dark Energy Survey (DES). We consider the cosmological correlation between the different tracers and we account for the systematic uncertainties that are shared between the large-scale lensing correlation functions and the small-scale lensing-based cluster mass calibration. Marginalized over the remaining Λ cold dark matter (ΛCDM) parameters (including the sum of neutrino masses) and 52 astrophysical modeling parameters, we measure ωm=0.300±0.017 and σ8=0.797±0.026. Compared to constraints from Planck primary cosmic microwave background (CMB) anisotropies, our constraints are only 15% wider with a probability to exceed of 0.22 (1.2σ) for the two-parameter difference. We further obtain S8σ8(ωm/0.3)0.5=0.796±0.013 which is lower than the Planck measurement at the 1.6σ level. The combined SPT cluster, DES 3×2pt, and Planck datasets mildly prefer a nonzero positive neutrino mass, with a 95% upper limit mν</p
[Abstract] AB0392 The relevance of joint instability to the hypermobile Ehlers Danlos syndrome phenotype
No full textBackground:Hypermobile Ehlers Danlos Syndrome (hEDS) is a connective tissue disorder causing excessive joint mobility, skin issues and chronic pain, with considerable biopsychosocial impact. Due to the ubiquity of connective tissue in the human body, hEDS often has multisystem involvement with an average of 10.45 co-diagnoses. The diagnosis of hEDS relies primarily on the Beighton score (a measure of hypermobility), which lacks consideration for the diversity of the hEDS phenotype. Joint instability may be a valuable diagnostic and prognostic measure for hEDS.Objectives:The primary aim of this study is to explore the relationship between joint instability and the extended joint hypermobility phenotype.Methods:This is a secondary data analysis of data collected as part of ISRCTN78820481. 87 participants were recruited on the basis of fibromyalgia, and fatigue (n63) and matched to controls (n24). Of these participants, 22 had experienced joint instability and 64 had not. Hypothesis tests were considered statistically significant for p values Results:Participants who had experienced joint instability, measured by dislocations or subluxation in the absence of trauma, were more likely to meet the Brighton Criteria for hEDS (Χ2(1) = 3.860, p =0.049) and have a higher Beighton Score, both current (t84= -2.359, p=0.021) and historical (t83= -4.021, p PAIN. Including, number of chronic pain sites (M=8.41 vs MC=5.33, t40.66= -2.694, p=0.010), total McGill pain score (M=14.94 vs MC=9.19, t70= -2.147, p= 0.035) and visual analogue score (M=7.33 vs MC=40.17, t41.79= -2.031, p= 0.049).FATIGUE. Measured by, meeting the Fukada criteria (Χ2(1) = 4.819, p =0.028) and Canadian criteria (Χ2(1) = 5.829, p =0.016), fatigue severity (M=52.90 vs MC=43.21, t57.91= -2.616, p =0.011), fatigue impact quotient (M=58.46 vs MC=40.17, t22.24= -2.652, p= 0.014) and total modified impact scale score (M=60.38 vs MC=41.14, t28.01= -2.690, p= 0.012).FIBROMYALGIA. demonstrated by, meeting the ACR criteria (Χ2(1) = 4.880, p =0.027), and severity of subsections: ACR symptom severity (M=7.95 vs MC=5.64, t45.45= -3.208, p= 0.002), and ACR widespread pain index (M=10.67vs MC=6.71, t83= -2.764, p=0.007)BRAIN FOG. Measured by mental clutter scale (M=34.79 vs MC=20.60, t24.077= -2.471, p= 0.021).ORTHOSTATIC INTOLERANCE. Measured by, total ASQOLS (M=119.71 vs MC=60.66, t19.26= -3.434, p= 0.003), and ASQOLS impact (M=48.93 vs MC=23.36, t59= -2.855, p= 0.006).Conclusion:In this study of 87 patients, joint instability, measured by dislocations or subluxation in the absence of trauma, was a useful diagnostic marker for hEDS, correlating strongly with the Beighton score, and the likelihood of meeting Brighton criteria. This may facilitate more rapid assessment and accurate diagnosis in this patient group. Further, joint instability was found to be strongly associated with several key clinical features, notably pain, fatigue, fibromyalgia, and orthostatic intolerance. Careful characterisation of the clinical phenotype in this patient group is critical to the provision of targeted management strategies to address both physical and mental health issues.</p
Beyond appearance and style: women’s embodied mediation of otherness in factual cinematic virtual reality
No full textEMBARGOED - expected end date 06.09.2028</p
Construction of Lyapunov functions for switched systems using meshfree collocation
No full textSwitched systems are a family of dynamical systems where a switching rule indicates which system is “switched on”. This rule can be dependent on time and/or position in the state space. Stability of switched systems is a property that is often investigated using the existence of one (or multiple) Lyapunov function(s). We develop an algorithm using a scattered approximation method to construct a Lyapunov function for switched systems, accompanied with stability results. The construction adapts a previous method for autonomous ODEs that uses meshfree collocation and quadratic programming.</p
Defining the boundaries of journalism and news publishers: implications of the Online Safety Act 2023 for the public interest and media freedom
No full textThis paper examines how provisions in the Online Safety Act 2023 (OSA), designed to protect journalism, may unintentionally create challenges to media freedom by enhancing platform power. By granting protections to news publisher content and journalistic content, the legislation requires platforms to determine who qualifies for these privileges, thereby making them gatekeepers of journalistic status. While news entities advocated for these provisions to protect themselves from content takedowns, we argue the OSA exemplifies what Tambini terms the ‘privilege paradox’ – where protecting journalism necessitates defining its boundaries, creating new ‘vectors of control’. Unlike jurisdictions such as Australia and Canada, which have established alternative mechanisms for determining what qualifies as journalism, the UK law places this power primarily with platforms. This approach, combined with questions about the enforceability of the OSA’s duty of care framework, may inadvertently strengthen the gatekeeping role of platforms over journalism rather than rebalancing power relations as intended.</p
A longitudinal exploration of self-perception, mental images of the self, and depression in young people
No full textBackground: Cognitive theories suggest that negative self-perception is central to the development and maintenance of depression. One way self-perception is represented is through mental imagery of the self. Despite its theoretical importance, the role of mental images of the self in depression has not been systematically examined. This study investigated cross-sectional and longitudinal associations between self-perception, mental images of the self, and depressive symptoms in young people. Methods: A total of 796 young people (aged 12-24) recruited from school and university populations completed surveys at two timepoints, one month apart. Measures included the Harter Self-perception Profile Global Self-Worth subscale, the Mental Imagery Questionnaire for Youths (MIQ-Y) and the Revised Child Anxiety and Depression Scale-Short Version (RCADS-25). Results: Self-perception was negatively associated with depressive symptoms both cross-sectionally and longitudinally (b=-2.57, 95% CI [-2.87, -2.27]; b=-0.83, 95% CI [-1.22, -0.45]). Positive and negative mental images of the self were associated with depressive symptoms (t=-5.61; t=10.73). Frequency of positive and negative images of the self were associated with self-perception (b=-0.57, 95% CI [-0.76, -0.39]; b=0.38 95% CI [0.18, 0.58]) and depression (b=0.12, 95% CI [0.09, 0.16]; b=-0.10, 95% CI [-0.14, -0.06]), cross-sectionally. Positive imagery vividness was linked to self-perception in the full sample (b=0.09, 95% CI [0.01, 0.16]) and school subgroup (b=0.14, 95% CI [0.03, 0.24], but not in the university subgroup. Longitudinally, both frequency and vividness of positive imagery were associated with self-perception in the university subgroup only (b=0.05, 95% CI [0.01, 0.10]; b=0.09, 95% CI [0.01, 0.16]). Conclusions: Young people’s self-perceptions, whether expressed through evaluative thoughts or mental images, play a critical role in depressive symptoms. Findings support cognitive models of depression and highlight self-perception as a promising intervention target. The study also underscores limitations of current mental imagery measures and the need for more robust tools to clarify these relationships.</p
Investigating the impact of social factors on gambling behaviour: a cross-disciplinary approach
No full textGambling disorder is a behavioural addiction characterized by continued gambling despite negative consequences, including the deterioration of close interpersonal relationships. Conversely, there are indications that social factors influence the progression of gambling disorder. However, the mechanisms through which these relationships may influence gambling behaviour remain largely unexplored. This thesis takes a cross-disciplinary approach incorporating both animal and human studies to explore how social interactions may influence gambling and gambling-like behaviour.First, an animal study was performed with the aim to incorporate and test the use of an alternative social reward in an animal model for gambling-like behaviour, and study its effects on choice behaviour. An animal model for gambling like behaviour was adapted so that animals were allowed a choice between a ‘gambling’ reward and social interaction. Additionally, it was examined how a risk factor - prior experience with uncertainty - later altered the development of gambling-like behaviour in rats, possibly in interaction with social isolation. Moreover, a pharmacological intervention was implemented using naltrexone to study its impact on ‘gambling’. Results revealed that regardless of prior exposure to uncertainty and housing conditions animals preferred to ‘gamble’ instead of interacting with a cage mate. Following efforts to devalue the ‘gambling’ reward there are strong indications that this preference is the result of habitual behaviour. Interestingly, despite the presence of habitual behaviours naltrexone seemed to heighten the motivation to lever press for the ‘gambling reward’ in animals previously exposed to uncertainty.Second, an online human study was conducted among the general population in the UK during the COVID-19 pandemic, to address the possible effects of the social restrictions on gambling behaviour. An online multi-phase study was distributed addressing social environment and both in-person and online gambling behaviour prior-to and during the pandemic. Moreover, the respondents had to complete mental health assessments and participated in an online gambling task to assess decision-making and risk-taking during the pandemic. Findings show that overall, in-person and remote gambling behaviour decreased, as well as gambling intensity. However, moderate non-significant trends were observed depending on type of modality used and game played. In addition, a majority of the participants adhered to the imposed social regulations, but it was found not to be associated with gambling. No differences were observed in decision-making and risk-taking between an early and late stage of the pandemic, and neither was mental health associated with decision-making and risk-taking across these time periods.</p
Impact of nature visibility on length of stay in the intermediate care unit: a quality improvement project
No full textBACKGROUND: The relationship between the natural environment and health outcomes has garnered significant attention in recent years. However, few studies have explored whether the benefit of nature visibility can be translated into measurable clinical outcomes in inpatient settings, such as length of stay.METHODOLOGY: This retrospective observational study investigated the impact of nature visibility from the patient's window on length of stay. Patients were sampled from two intermediate care units in Sussex, and the nature visibility from their window was classified into three predefined categories. A generalised linear model was used to analyse length of stay, while controlling for potential confounding factors.RESULTS: The final analysis included 459 patients. Nature visibility was a significant predictor (p=0.016) of an inpatient length of stay. However, seasonality (p=0.438) did not impact the effect of nature visibility on length of stay. Hospital location (p=0.020) and discharge age (pDISCUSSION: The results demonstrated an ~8.7% decrease in length of stay for every increase in nature visibility category, regardless of the season. The study findings emphasise the value of non-pharmaceutical interventions in patient recovery and contribute to the idea of patient-centred care.</p