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How do Artificial Intelligence chatbots respond to questions from adolescent personas about their eating, body weight, or appearance?
No full textBackground: Body image and eating behaviours are common areas of concern for earlyadolescents. Artificial Intelligence (AI) interactions are becoming commonplace, includingwith chatbots that provide human-like communication. Adolescents may prefer usingchatbots to anonymously ask sensitive questions, rather than approaching trusted adults orpeers. It is unclear how chatbots answer such questions. We explored how chatbots wouldrespond to eating, weight, or appearance-related queries from adolescents.Method: Ten fictitious adolescent personas and scripts were created to facilitateconversations with ChatGPT and Claude.AI. Personas asked questions about eating, bodyweight and/or appearance, presenting as “curious”, “worried”, or “having a potential eatingdisorder”. Conversation outputs were analysed using reflexive thematic analysis to explorethe content of chatbot responses.Results: Five themes were identified: 1) Live a “healthy” adolescent lifestyle; 2) Eat“healthily”; 3) Promoting regular physical activity; 4) Seek support; 5) Focus on you. Advicewas often framed within societal ideals relating to eating, body weight and/or appearance.Chatbots signposted to trusted adults and healthcare professionals for support, but not toregulated resources (e.g., NHS).Conclusions: Framings around eating, weight and/or appearance may be problematic foradolescents with eating disorder symptomatology. A lack of prompting for furtherinformation or signposting to regulated support means vulnerable adolescents may receiveunhelpful information or not reach adequate support. Understanding how AI could besupportive and/or unhelpful to adolescent users presenting with eating, body or appearance-related concerns is important. Findings can inform policy regulating AI chatbots’communications with adolescents.</p
Spatial dynamic panel data model with interactive fixed effects and time-variant endogenous spatial weight matrices
No full textA novel spatial dynamic panel data (SDPD) model is proposed, incorporating interactive fixed effects and time-varying endogenous spatial weight matrices. The framework captures evolving spatial spillovers and latent heterogeneity without imposing restrictions on the relationship between unobserved factors in the outcome and auxiliary equations. A quasi-maximum likelihood estimator (QMLE) with finite-sample bias correction is developed, and its asymptotic distribution is established using perturbation expansions of linear operators. Monte Carlo simulations show that the estimator performs robustly across various factor configurations, endogeneity levels, and degrees of spatial dependence. An empirical study on U.S. state-level reverse mortgage activity from 2001Q1 to 2013Q4 demonstrates the model's effectiveness in capturing dynamic spatial interactions in regional financial behavior.</p
Urgent Need for Standardization in CGM Performance Assessment
No full textThe increasing use of continuous glucose monitoring (CGM) systems in both clinical care and research underscores the urgent need for standardized performance assessment protocols. Recent evidence suggests that CGM systems may vary in how accurately they report glucose concentrations, particularly when referenced against capillary glucose measurements, the compartment that typically reflects the highest postprandial excursions.</p
A fast gray-box adversarial example generation algorithm based on FakeBob
No full textThere are the excessive queries to the targeted model during the generates of gray-box adversarial examples for speaker recognition systems, which result in high costs of attacks. In this paper, a fast generates algorithm of gray-box adversarial example is proposed based on FakeBob, named F-FakeBob. This algorithm introduces a threshold mechanism for optimization to the optimization strategy of gradient. Only when the increasing of the confidence scores of the adversarial example before and after optimizing is less than the threshold, the gradient is recalculated for the next iteration. By reducing the frequency of gradient calculations, the number of queries to the targeted system is decreased. Experiments on three public datasets of speech, TIMIT, Common Voice, and Voxceleb2, are conducted to generate adversarial examples. The targeted speaker recognition models are based on ECAPA-TDNN and TitaNet architectures. The experimental results show that F-FakeBob can achieve a targeted attack success rate of 99.2% and the numbers of queries are effectively reduced in the adversarial example generates, with an average query reduction of 25.71% compared to FakeBob.</p
Systematic review and meta-analysis of educational approaches to reduce cognitive biases among students
No full textResistance to cognitive biases is a crucial element of rationality that influences judgement and decision-making. Here we synthesized the effects of debiasing training in educational settings. Our systematic review found 54 randomized controlled trials consisting of 383 effect sizes and 10,941 participants. Our meta-analysis of educational interventions showed a small, yet significant, improvement in reducing the likelihood of committing biases compared with control conditions (g = 0.26, 95% confidence interval 0.14 to 0.39), 160 effects from 41 studies, P </p
Evaluating amyloid-beta as a surrogate endpoint in trials of anti-amyloid-beta drugs in Alzheimer's disease: a Bayesian meta-analysis
No full textAim: The use of amyloid-beta (Aβ) clearance to support regulatory approvals of drugs in Alzheimer's disease (AD) remains controversial. We evaluate Aβ as a potential trial-level surrogate endpoint for clinical function in AD. Materials & methods: Data on the effectiveness of anti-Aβ monoclonal antibodies (MABs) on Aβ and multiple clinical outcomes were identified from randomized controlled trials through a literature review. A Bayesian bivariate meta-analysis was used to evaluate Aβ as a surrogate endpoint for clinical function across all MABs and for each individual anti-Aβ MAB. The analysis for individual therapies was conducted in subgroups of treatments and by applying Bayesian hierarchical models to borrow information across treatments. Results: We identified 23 randomized controlled trials with 39 treatment contrasts for seven MABs. The surrogate relationship between treatment effects on Aβ and Clinical Dementia Rating-Sum of Boxes (CDR-SOB) across all MABs was strong: with a meaningful slope of 1.41 (0.60, 2.21) and small variance of 0.02 (0.00, 0.05). For individual treatments, the surrogate relationships were suboptimal, displaying large uncertainty. Sharing information across treatments considerably reduced the uncertainty, resulting in moderate surrogate relationships for aducanumab and lecanemab. No meaningful association was detected for other clinical outcomes, including Mini Mental State Examination and Alzheimer's Disease Assessment Scale-Cognitive Subscale. Conclusion: Although our results from the analysis of data across all MABs suggested that Aβ was a potential surrogate endpoint for CDR-SOB, individually the surrogacy patterns varied across treatments and showed no evidence of association. Bayesian information-sharing revealed moderate surrogate relationship only for aducanumab and lecanemab.</p
Transition Characteristics and Drivers of Land Use Functions in the Resource-Based Region: A Case Study of Shenmu City, China
No full textResource-based regions play an indispensable role as strategic bases for national energy and raw material supply in the global industrialization and urbanization process. However, intensive and large-scale natural resource exploitation—particularly mineral extraction—often triggers dramatic land use/cover changes, leading to a series of problems including cultivated land degradation, ecological function deterioration, and human settlement environment degradation. However, a systematic understanding of the functional transitions within the land use system and their drivers in such regions remains limited. This study takes Shenmu City, a typical resource-based city in the ecologically vulnerable Loess Plateau, as a case study to systematically analyze the transition characteristics and driving mechanisms of land use functions from 2000 to 2020. By constructing an integrated “element–structure–function” analytical framework and employing a suite of methods, including land use transfer matrix, Spearman correlation analysis, and random forest with SHAP interpretation, we reveal the complex spatiotemporal evolution patterns of production–living–ecological functions and their interactions. The results demonstrate that Shenmu City has undergone rapid land use transformation, with the total transition area increasing from 27,394.11 ha during 2000–2010 to 43,890.21 ha during 2010–2020. Grassland served as the primary transition source, accounting for 66.5% of the total transition area, while artificial surfaces became the main transition destination, receiving 38.6% of the transferred area. The human footprint index (SHAP importance: 4.011) and precipitation (2.025) emerged as the dominant factors driving land use functional transitions. Functional interactions exhibited dynamic changes, with synergistic relationships predominating but showing signs of weakening in later periods. The findings provide scientific evidence and a transferable analytical framework for territorial space optimization and ecological restoration management not only in Shenmu but also in analogous resource-based regions facing similar development–environment conflicts.</p
Proline Amide Catalyzes Formation of Toxic Crotonaldehyde from Acetaldehyde Under Physiologically Relevant Conditions.
No full textCrotonaldehyde is a human toxin that reacts with nucleophilic groups on DNA and proteins. Putative crotonaldehyde-derived adducts on DNA are reported in cells and patients after ethanol exposure, which implies that crotonaldehyde is formed in cells. Here, we show that proline amide, which is a model of N-terminal proline-containing proteins, catalyzes the aldol condensation of the ethanol metabolite acetaldehyde to crotonaldehyde under physiologically relevant conditions. This reaction is more efficient at neutral pH than under acidic or basic conditions, but is inhibited by competing imidazolidin-4-one formation. Crotonaldehyde formation is also slower than the analogous aldol condensation of propionaldehyde. Comparative studies additionally suggest that proline amide is a more efficient catalyst than other amino acid amides. Overall, the work evidences a biochemically plausible mechanism for intracellular crotonaldehyde formation and implies that proline amide derivatives can catalyze aldol chemistry in humans.</p
Police leadership and legitimacy in the context of a global pandemic
No full textThis article provides original insight into police legitimacy through the lens of senior police leaders using interview data from 26 police practitioners in leadership positions during the COVID-19 pandemic. Exploring situational contexts affecting their perceptions of self-legitimacy, it highlights competing legitimacy expectations from public audiences and elite powerholders that are exacerbated in prolonged periods of crisis. When faced with seemingly irresolvable tensions threatening their legitimacy, it demonstrates that police leaders promote audience legitimacy over the expectations and demands of elite powerholders. Cultivating their self-legitimacy by reflecting on internal audience stressors and seeking to preserve the public legitimacy of the police, this article highlights the importance of understanding police leader sense-making and self-legitimacy as highly contextual and situational. This raises questions about how police leaders conceptualise public legitimacy and normative expectations of the police role and community relations, suggesting these might be malleable and dynamic across different complex and demanding circumstances.</p
Thermal-hydraulic and structural analysis of a liquid-cooled heat sink with rotating twisted tape inserts
No full textThis study investigates advanced thermal management techniques for liquid-cooled electronics, aiming to enhance cooling efficiency through innovative rotating twisted tape inserts in the heat sink. A water-cooled heat sink is analysed at an inlet temperature of 300 K, with Reynolds numbers ranging from 100 to 400, and a heat flux of 180,000 W/m2. Five configurations are examined: a base case, a stationary twisted tape (ω = 0 rpm), and rotating twisted tapes at 300, 600, and 900 rpm. Results show that both stationary and rotating twisted tapes significantly reduce the base plate temperature compared to the base case. At Re = 400, temperature drops of 10.73 K, 13.12 K, 15.36 K, and 16.24 K are observed with ω = 0, 300, 600, and 900 rpm, respectively, demonstrating improved thermal performance that can enhance the reliability and lifespan of cooled electronics. While stationary tapes increase the friction factor due to intensified fluid-wall interactions, rotating tapes decrease the axial pressure drop by increasing fluid momentum. Fluid-structure interaction analysis indicates minimal deformation in copper and aluminium tapes, with maximum displacement occurring axially. Aluminium shows slightly higher deformation (2.850 × 10−5 mm) than copper (1.605 × 10−5 mm). These findings offer valuable insights for optimising thermal–hydraulic performance and structural integrity in electronic cooling systems.</p