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Discrete incremental voting on expanders
Get PDFPull voting is a random process in which vertices of a connected graph have initial opinions chosen from a set of k distinct opinions, and at each step a random vertex alters its opinion to that of a randomly chosen neighbour until the system reaches a state where each vertex holds the same opinion. In general the opinions of the vertices in pull voting are regarded as incommensurate, whereas we consider a type of pull voting, which we call discrete incremental voting, suitable for moving towards consensus on integer opinions such as {1,2,…,k}. On observing the opinion of a random neighbour, the vertex updates its opinion by a discrete change in the direction of the neighbour's opinion, if different. In the simplest case, the vertex increases its opinion by +1 if the opinion of the chosen neighbour is larger, or decreases its opinion by −1, if the opinion of the neighbour is smaller. If initially there are only two adjacent integer opinions, incremental voting coincides with pull voting, whereas if there are more than two opinions this is not the case. Let G=(V,E) be a connected non-bipartite n-vertex graph, and let λ be the absolute second eigenvalue of the transition matrix P of a simple random walk on G with stationary distribution π=(π v) v∈V. Let the initial opinions of the vertices be chosen from {1,2,…,k}, let X v be the initial opinion of vertex v, and let c=∑ v∈Vπ vX v be the initial weighted average opinion. We show that provided λk=o(1) and k=o(n/logn) the following holds with high probability. If c is integer then the final opinion is c. Otherwise the final opinion is ⌊c⌋ with probability ⌈c⌉−c, and ⌈c⌉ with probability 1−(⌈c⌉−c). In particular if G is a regular graph, and c is the initial unweighted average opinion, then with high probability the final opinion held by all vertices is either ⌊c⌋ or ⌈c⌉, the rounded values of the initial average.</p
Beyond Gestational Diabetes:Maternal and Offspring Health and Lifestyle 3 years Postnatally in a secondary analysis of the UPBEAT Trial Cohort
Get PDFBackground: Gestational diabetes (GDM) is associated with increased future obesity risk in affected mothers and children. Objective: We assessed if dietary behaviours learnt during a GDM pregnancy positively impact maternal and child health 3 years postpartum. Method: In a secondary analysis, we included women with obesity recruited to the UPBEAT randomised controlled trial with 3-year follow-up postnatally (n = 441). Maternal and offspring anthropometry and dietary data were recorded antenatally and at follow-up. Data were assessed using linear/logistic regression, adjusting for confounders. Results: Women with GDM (22%) had higher BMI (median 35.6 vs. 34.2 kg/m 2; p = 0.049) and energy intake (1738.2 vs. 1551.6 kcal/day; p = 0.005) at ~16 weeks' gestation compared to unaffected women, but lower gestational weight gain (4.5 kg vs. 6.6 kg; p < 0.001). However, at 3 years postpartum BMI was similar between groups (35.8 vs. 35.2 kg/m 2; p > 0.5). GDM-exposed infants had a higher birthweight (55.4 vs. 45.9th centile; p = 0.008) than unexposed infants and at 3 years of age were more likely to be overweight/obese (International Obesity Task Force, IOTF, standards; OR 2.32; 95% CI 1.38, 3.91) but with similar skinfold thicknesses and dietary patterns. Conclusion: Women with GDM demonstrated reduced gestational weight gain, and despite a higher BMI than women without GDM in early pregnancy, this difference was not evident at 3 years postpartum. However, while maternal and offspring dietary behaviours were comparable between groups, exposed offspring were at increased risk of overweight/obesity at 3 years of age.</p
Super-MoCo-MoDL:A combined super-resolution and motion-corrected undersampled deep-learning reconstruction framework for three-dimensional whole-heart cardiac magnetic resonance imaging
No full textBACKGROUND: Cardiac magnetic resonance (CMR) is a well-established imaging modality for the assessment of cardiovascular diseases. However, attainable image resolution remains lower than that of X-ray computed tomography (CT) due to long scan times and the need for respiratory motion correction. In this work, we combine a previously proposed motion-corrected model-based deep-learning reconstruction for undersampled 3D whole-heart CMR with data-consistent super-resolution to enable high-resolution 3D whole-heart CMR from significantly shortened scans.METHODS: Our proposed framework, Super-MoCo-MoDL, utilises two neural networks; the first estimates non-rigid respiratory motion from zero-padded and zero-filled bin images, the second applies these fields in an iterative motion-corrected model-based ADMM (alternating direction method of multipliers) reconstruction which alternates between applying a super-resolving U-Net and imposing data-consistency in the acquired centre of k-space. The framework was trained using 156 isotropic-resolution free-breathing 3D datasets. It was subsequently applied to prospective anisotropic low-resolution free-breathing 3D data acquired in a cohort of congenital heart disease (CHD) patients, and to prospective undersampled and low-resolution data acquired in a cohort of patients with suspected coronary artery disease (CAD).RESULTS: Isotropic resolution whole-heart 3D images were reconstructed from ~ 0.8- and ~ 2.1-minute scans, for CHD patients at 1.5-mm resolution and suspected-CAD patients at 0.9-mm resolution, respectively, representing an overall scan acceleration of ~ 18-fold in each case. Visual inspection, expert image quality scores and rankings, and quantitative vessel sharpness measurements demonstrated that the Super-MoCo-MoDL reconstructions produced sharp high-quality images that were comparable with high-resolution acquisitions. For patients with suspected CAD, comparison was made with computed tomography coronoary angiography (CTCA), demonstrating that coronary plaque visualisation was possible with the Super-MoCo-MoDL technique.CONCLUSION: Super-MoCo-MoDL is able to reconstruct high-resolution 3D whole-heart images from low-resolution and undersampled anisotropic acquisitions.</p
Genetic and environmental risk factors for major depression in UK women and their association with telomere length longitudinally
Get PDFBackgroundMajor depressive disorder (MDD) is more prevalent in women and associated with shorter telomere length, a marker of biological ageing, and an increased risk of age-related disease. However, the precise influence of depression-related genetic and environmental risk factors on telomere dynamics remains a topic of debate.MethodsWe examined leukocyte relative telomere length (RTL) and longitudinal telomere attrition in 958 women (median age: 58 years) from the TwinsUK cohort. RTL was measured using quantitative PCR from up to four timepoints. Associations with self-reported depression, antidepressant use, lifestyle and socioeconomic factors, and polygenic risk scores (PGS) for MDD and comorbid age-related diseases were assessed using linear mixed models.ResultsOver a median 6-year follow-up, telomere length declined annually by 1.3 % of baseline RTL. Depression showed a borderline association with shorter RTL (p = 0.06), while a nominal association was observed between antidepressant use and shorter RTL (p = 0.02), replicating previous findings. No significant associations were observed for PGS related to MDD. PGS for coronary artery disease was associated with shorter RTL (p = 0.02), while other trait PGS showed inconsistent associations with RTL or attrition. Higher waist-to-hip ratio was associated with faster telomere attrition longitudinally (p = 0.01).ConclusionsOur findings suggest depression and its genetic liability are not directly associated with telomere length or attrition in older women. In contrast, waist-to-hip ratio, a modifiable factor, was linked to accelerated telomere shortening, pointing to central adiposity as a potential intervention target with relevance for both mental and physical health
When Is the Right Time to End Family Therapy for Anorexia Nervosa (FT-AN)?:A Qualitative Study of Young People's Experiences
No full textObjective: Family therapy for anorexia nervosa (FT‐AN) is the first‐line recommended treatment for young people with anorexia nervosa. There is variability in treatment length across studies and evidence suggests treatment length and outcome are not necessarily linearly related. This makes it difficult to identify the optimum length of treatment in clinical practice. This study aimed to explore young people's perspectives on the timing of discharge and how this relates to recovery. Method: Twenty three young people (age 12–18) diagnosed with anorexia (or atypical anorexia) nervosa participated. All had completed FT‐AN with or without adjunctive multi‐family therapy. Semi‐structured individual qualitative interviews were conducted. Recordings were transcribed verbatim and analysed using reflexive thematic analysis. Results: Four inter‐connected themes were generated; (1) who decides?, (2) knowing what's coming, (3) things that need to be in place, (4) discharge is a necessary step towards recovery. Discussion: Young people said that remaining in treatment for longer than necessary may impede recovery. Establishing clear expectations about discharge and recovery, helping young people to commit to ongoing behaviour change, and building their support network were all described as important components in helping them to feel confident about discharge and to take ownership of continuing the recovery journey post‐discharge
Stakeholder engagement with AI service interactions
No full textRecent advancements in artificial intelligence (AI) have ushered in a wave of AI innovations in the form of embodied conversational agents. These stakeholders offer new ways to engage customers in the co-creation of services but still face significant customer skepticism. To address this challenge, we frame interactions between customers and embodied conversational agents through the lens of stakeholder engagement and apply the concept of proxy agency from social cognitive theory. This framework allows us to identify two primary stakeholder roles for embodied conversational agents: partner and servant. We conceptualize how these roles inform optimal design for embodied conversational agents and shape a two-stage value-by-proxy process, comprising proxy efficacy and outcome expectancy. Additionally, we uncover tensions within this process due to over-reliance on AI, as well as significant outcomes that extend beyond the immediate interaction. Our study, using a custom-developed embodied conversational agent with a sample of 596 U.S.-based respondents, reveals that positioning an embodied conversational agent in a partner role, combined with a human (vs. robot) appearance and emotional (vs. functional) conversation style, has the strongest positive impact on perceived value-by-proxy, usage and advice implementation intentions, and willingness to pay. We also observe an inverted U-shaped moderation by reliance in the relationship between proxy efficacy and outcome expectancy, signaling the potential risks of over-reliance on AI. Furthermore, we provide qualitative insights into why some customers avoid engaging with embodied conversational agents. Overall, we offer a nuanced perspective on embodied conversational agents as active stakeholders within organizational systems, advancing both theoretical understanding and practical applications of this rapidly evolving technology.</p
Understanding Lived Experience-Driven Co-production in Health and Social Services:The Sowing and Growing Model
No full textInvestigating the influence of maternal prenatal BMI and perinatal depressive symptoms on neonatal brain network dynamics
Get PDFBackgroundElevated pre-pregnancy body mass index (BMI) and perinatal depressive symptoms have been linked to neonatal alterations in brain structure and function. This study examined associations between neonatal functional brain dynamics, maternal BMI, and perinatal depressive symptoms measured by the Edinburgh Postnatal Depression Scale (EPDS) in a community-based, largely low-risk cohort. MethodsFuncitonal MRI and Leading Eigenvector Analysis (LEiDA) were applied in a neonatal cohort (N = 437; 236 males; mean gestational age 39.6 weeks) from the developing Human Connectome Project. We assessed whether neonatal brain-state probabilities related to maternal BMI and EPDS scores (M = 5.6, SD = 4.3), testing main effects and, separately, their interaction. The sample included 291 healthy-weight (BMI < 25), 98 overweight (25 BMI < 30), and 48 obese (BMI 30) mothers. ResultsEPDS scores were low in this cohort and did not demonstrate associations with brain states or a significant BMI × EPDS interaction. Higher maternal pre-pregnancy BMI was negatively associated with the stability of a functional network encompassing superior frontal, superior parietal, and temporal regions (ß = −0.129, p = 0.006). ConclusionAs this network is normally recruited more with age, reduced stability suggests slowed maturation of fronto-parieto-temporal systems and may signal early risk for later behavioral challenges. Impact: Higher maternal pre-pregnancy BMI is associated with reduced stability in a neonatal frontoparietal brain state, characterized by coordinated activity in frontal, parietal, and temporal regions. This state is one of six distinct dynamic connectivity patterns identified, reflecting core neonatal resting-state networks. The association was robust across multiple analytic models and clustering solutions. No significant effects were found for maternal depressive symptoms. These findings underscore the selective impact of maternal metabolic health on early brain organization, suggesting prenatal influences on the functional architecture of the newborn brain that may shape long-term neurodevelopmental trajectories.</p
Co-Designing a Multimodal Physical Activity Intervention for Individuals With Young-Onset Type 2 Diabetes (18–40 Years) in China
Get PDFBackgroundA limited number of physical activity programmes exist for Chinese people with young-onset (18–40 years) type 2 diabetes amid its rising global prevalence. This study aims to develop a multimodal intervention for improving physical activity levels for individuals with young-onset type 2 diabetes using co-design. MethodsThe development process included three stages. Stage 1 involved synthesising the findings of a review of existing physical activity interventions and a qualitative study of exercise experiences of young adults with type 2 diabetes. This generated a list of candidate intervention elements and behaviour change techniques to inform the co-design process. Stage 2 involved the development of animated trigger films, using findings from stage 1, to present the physical activity experiences of people with young-onset type 2 diabetes. In stage 3, a series of co-design workshops engaging relevant stakeholders were conducted, utilising the outputs from the previous two stages and aligning with the Design Thinking theory. ResultsTwenty-five participants (12 young adults with type 2 diabetes, 12 healthcare professionals, and one family member) attended co-design workshops to develop the intervention. The co-design process resulted in a logic model for a tailored programme–IPAYD (Improving Physical Activity in people with Young-onset type 2 Diabetes). This programme integrates behaviour change techniques across four elements: individualised goal setting and planning, exercise monitoring, a peer support forum, and educational resources. An eHealth platform was preferred to deliver the programme, incorporating one-to-one consultations and optional group sessions to enhance social support and social interaction. ConclusionsThrough stakeholder engagement in a co-design process, this study makes a novel and much-needed contribution to developing a physical activity intervention for Chinese people with young-onset type 2 diabetes. Patient and Public ContributionAn advisory group of six Chinese young people with type 2 diabetes met online and communicated through a project-focused WeChat group. They contributed to the animated film scripts, the topic guide of the workshops, the design of the intervention materials, and how to conduct the workshops to align with Chinese culture.</p
