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A mathematical framework for misinformation propagation in complex networks:Topology-dependent distortion and control
Get PDFMisinformation is pervasive in natural, biological, social, and engineered systems, yet its quantitative characterization remains challenging due to context-dependent errors and the heterogeneous structure of real-world interaction networks. We develop a general mathematical framework for quantifying information distortion in distributed systems by modeling how local transmission errors accumulate along network geodesics and reshape each agent’s perceived global state. Through a drift–fluctuation decomposition of pathwise binomial noise, we derive closed-form expressions for node-level perception distributions and show that directional bias induces only a uniform shift in the mean, preserving the fluctuation structure. This establishes a previously unreported shift-invariance principle governing error propagation in networks. Applying the framework to canonical graph ensembles, we uncover strong topological signatures of misinformation: Erdős–Rényi random graphs exhibit a double-peaked distortion profile driven by connectivity transitions and geodesic-length fluctuations, scale-free networks suppress misinformation through hub-mediated integration, and optimally rewired small-world networks achieve comparable suppression by balancing clustering with short paths. A direct comparison across regular lattices, Erdős–Rényi random graphs, Watts–Strogatz small-world networks, and Barabási–Albert scale-free networks reveals a connectivity-dependent crossover. In the extremely sparse regime, scale-free and Erdős–Rényi networks behave similarly. At intermediate sparsity, Watts–Strogatz small-world networks exhibit the lowest misinformation. In contrast, Barabási–Albert scale-free networks maintain low misinformation in sparse and dense regimes, while regular lattices produce the highest distortion across connectivities. We additionally show how sparsity constraints, structural organization, and connection costs delineate regimes of minimal misinformation. Overall, our results provide an analytically tractable foundation for understanding and controlling information reliability in complex networked systems
Game theory approaches to hydrogen infrastructure investment planning in Great Britain:A comparative analysis of competitive and cooperative frameworks
Get PDFAchieving Great Britain’s 2050 net-zero target requires coordinated integration of electricity, gas, and hydrogen systems. This paper presents a game-theoretic optimisation framework that evaluates competitive and cooperative investment and operational strategies within a bi-level structure combining long-term planning and short-term operational constraints. The competitive scenario is modelled through a Nash–Cournot equilibrium, while the cooperative scenario applies the Shapley value to ensure a fair allocation of costs and benefits among technologies. Results show that both approaches enable decarbonisation, but cooperation delivers superior economic efficiency at the 2050 peak demand, achieving a 57% reduction in operational costs and complete decarbonisation, compared to residual emissions of 8161 tonnes under competition. Competitive strategies favour flexibility technologies such as Power-to-Gas (P2G) (11.7%) and Battery Energy Storage (BESS) (11.4%), whereas cooperative planning utilises lower flexibility (P2G 3.4%, BESS 4.5%) and greater nuclear baseload (20%–26%). Shapley value analysis quantifies each technology’s marginal contribution, identifying hydrogen technologies as major value drivers, while gas-to-hydrogen reforming with carbon capture and storage (G2G-CCS), biomass, and combined heat and power (CHP) require policy support. When market conditions are not favourable, electricity technologies require between £0.82 and 2.16 million in financial support. The paper findings offer quantitative insights to guide policy development that incentivises collaboration and coordinated planning, supporting a resilient, fair, and economically efficient pathway to a net-zero energy system for Great Britain
Womb, Print, Imprint:Birth Figures and the Shaping of the Early Modern Pregnant Body
Get PDFIn the early modern period, women found relief from the dangers and uncertainties of pregnancy and childbirth in the strange power of maternal imagination. While most historical study on this subject has focussed on unintended and negative outcomes – horrible sights and unsated cravings producing deformed and “monstrous” children – this article explores maternal imagination as a tool used consciously by women to take control of their pregnancies and produce healthy and well-formed children. Looking specifically at “birth figures” – medical images of the fetus in the womb which describe varieties of presentation – this article explores not only how the images could be understood as positive representations of infancy and models for maternal imagination, but also how the print medium contributed to the power of the images to impress both the mind, and the womb, of the pregnant viewer.-----------------------------------------------------------------------------------------À l’époque moderne, les femmes trouvaient un certain réconfort face aux dangers et aux incertitudes de la grossesse et de l’accouchement dans l’étrange pouvoir de l’imagination maternelle. Tandis que la plupart des études historiques sur ce sujet se sont concentrées sur ses effets involontaires et souvent néfastes – visions terrifiantes et envies inassouvies engendrant des enfants difformes ou « monstrueux » – cet article explore une autre facette de cette imagination : son usage conscient par les femmes pour maîtriser leur grossesse et donner naissance à des enfants en bonne santé et bien formés. En s’intéressant plus particulièrement aux « figures de naissance » – ces images médicales illustrant les différentes positions du fœtus dans l’utérus – cet article examine non seulement la façon dont elles pouvaient être perçues comme des représentations positives de l’enfance et des modèles pour l’imagination maternelle, mais aussi le rôle du médium imprimé dans leur capacité à marquer à la fois l’esprit et le corps des femmes enceintes
Anti-collusion leniency legislations and IPO activity:Worldwide evidence
No full textWe study the impact of the staggered adoption of anti-collusion leniency legislations around the world on IPO activity. We document that the passage of leniency legislations prompts IPO activity. The effect is amplified in more concentrated industries, while it is mitigated in countries with more stringent competition laws in place and countries in which investors have a lower ability to diversify risk in the financial market. Collectively, these findings are consistent with the view that, by enhancing product market competition, leniency legislations increase the benefits for firms from going public, resulting in higher IPO activity. The results of supplemental analyses suggest that the passage of leniency legislations leads to less underpriced IPOs and a more efficient use of IPO proceeds, and prompts firms with less proprietary information to go public
Computing the endomorphism ring of a supersingular elliptic curve from a full rank suborder
No full textIn this paper, we study the problem of computing the endomorphism ring of a supersingular elliptic curve given the knowledge of a full rank suborder. We provide a polynomial time quantum algorithm to solve this problem in full generality. This result enhances our understanding of the endomorphism ring problem, which is at the core of isogeny-based cryptography. As part of our approach, we also present a polynomial time quantum algorithm to solve the problem of computing the endomorphism ring of the codomain curve of an isogeny from a curve with known endomorphism ring. This extends the work of [CII+23a] by lifting their restrictions on the number of factors of the isogeny degree. As an application, we present quantum reductions between key hard problems in isogeny-based cryptography. We show that some of our quantum reductions are tighter than the classical ones, while all reductions are of polynomial time complexity. In particular, we improve the query complexity of the reduction of the EndRing problem to the OneEnd problem from poly(logp) (classically) to O(1) (quantumly), strengthening the hardness assumption of the OneEnd problem in the post-quantum setting. This reduction underlies the 2-special soundness proof of SQIsign identification protocols
Code-based Fully Dynamic Accountable Ring Signatures and Group Signatures using the Helper Methodology
No full textIn this paper, we propose an efficient code-based accountable ring signature scheme based on the proof with helper paradigm. Our main technical contribution is a zero-knowledge OR proof based on the helper protocol of Beullens (Eurocrypt 2020). Combined with the Niederreiter encryption scheme, we leverage the framework of Beullens et al. (Eurocrypt 2022) to construct our accountable ring signature. We apply our construction to develop a code-based dynamic group signature scheme that simultaneously achieves a logarithmic signature size and the strongest security notion for full anonymity and unforgeability. Our construction results in a relatively short group signatures—just 51kB for a group of members at the 128-bit security level—while maintaining the strongest security guarantees. In comparison, two recent code-based group signature schemes proposed at PKC 2024 and Asiacrypt 2024 achieve signature sizes of 146kB and 124kB, respectively, for the same number of users
Rising energy costs and heterogeneous innovation outcomes in Thailand
No full textWe present the first firm-level study examining the causal relationship between innovation and rising energy costs in Thailand. Employing the most comprehensive set of innovation measures in the literature, we provide robust evidence that higher energy costs significantly drive firms to innovate across four key dimensions: product, process, marketing, and organizational innovation. Specifically, a one-unit increase in energy costs makes firms 3.3 times more likely to engage in at least one form of innovation compared to not innovating. However, this likelihood declines to 2.5 times for firms pursuing two types of innovation concurrently, and no significant effect is observed for firms engaging in three or more types simultaneously. We leverage an instrumental variables strategy based on geographic variations in energy consumption patterns and show that rising energy costs independently spur innovation not only in broad categories but also in specific areas such as automation, adoption of new technologies, and radical product development. These findings have important policy implications: while rising energy costs are often viewed as detrimental to economic growth, our results suggest that well-designed innovation policies can mitigate these effects and generate positive externalities. Policymakers should consider aligning energy and innovation strategies to foster economic resilience and long-term growth in the face of escalating energy costs
Comprehensive Analysis of Psychological, Social and Clinical Aspects of Polycystic Ovary Syndrome in Pregnancy:Insights From the Born in Bradford Cohort Study
No full textINTRODUCTION: Polycystic ovary syndrome (PCOS) presents complex challenges during pregnancy, affecting both maternal and neonatal health. This study aims to provide a comprehensive analysis of the demographic, social and clinical dimensions of PCOS in pregnancy, utilising data from the Born in Bradford (BiB) cohort.METHODS: A retrospective cohort study used data from the BiB cohort, including pregnant women with PCOS and a control group. Demographic, social, and clinical characteristics were analysed, with data collected from electronic health records, maternal questionnaires, and medical records. The General Health Questionnaire-28 (GHQ-28) assessed overall well-being and psychological distress. Statistical analysis included descriptive statistics, Fischer's exact tests, independent t-tests, Mann-Whitney U tests, and logistic regression analysis.RESULTS: The study included 279 pregnant women diagnosed with PCOS and 10,284 controls. After adjusting for age, women with PCOS had significantly higher GHQ-28 scores than controls (β = 2.65, SD = 0.86, p = 0.002). PCOS was associated with significantly increased odds of pre-eclampsia (OR: 2.09, 95% CI: 1.18-3.71, p = 0.01) and gestational hypertension (OR: 1.69, 95% CI: 1.19-2.38, p = 0.005). However, after adjusting for BMI, the association between PCOS and pre-eclampsia was no longer significant, though mediation analysis confirmed that BMI played a significant mediating role. Infants born to mothers with PCOS had significantly higher odds of stillbirth (OR: 4.93, 95% CI: 1.92-12.62, p = 0.005) and lower overall birth weights. A gender-stratified analysis showed that the reduction in birth weight was particularly pronounced in female infants (3164.5 ± 535.7 g vs. 3011.2 ± 581.0 g; p = 0.004), whereas no significant difference was observed in male infants (p > 0.05).CONCLUSION: The findings underscore the importance of considering demographic, social, and clinical factors in the management of pregnant women with PCOS.</p
Evaluating long-term thermal performance and soil recovery in energy piles under various operational modes
Get PDFEnergy piles present a feasible solution for heating and cooling decarbonisation and offer economic advantages. However, their widespread adoption is constrained by limited understanding of long-term performance. This study employs a validated, fully coupled three-dimensional thermo-hydro-mechanical numerical model to investigate long-term thermal performance of energy piles under different operational strategies. The model examines continuous operation (Mode 1), seasonal stoppage (Mode 2), and an idealised daily stoppage mode (Mode 3) over both short-term (1-year) and long-term (10-year) cycles. Results show that daily stoppage (Mode 3) limits cumulative soil temperature drift to ±2 °C after ten years, compared to over 6 °C under continuous loading. Mode 3 also yields the most stable outlet fluid temperatures, outperforming Mode 1 by up to 2 °C in cooling efficiency. Thermal impacts are spatially confined, with 90 % of recovery occurring within a 4 m radius from the pile. Mode 3, as an ideal operational strategy, establishes a performance benchmark for ground recovery and system energy efficiency. These findings highlight the importance of load scheduling in mitigating ground thermal degradation and enhancing long-term performance. The results provide a basis for integrating energy piles into seasonal thermal storage or hybrid heating systems and guiding future smart control strategies.<br/
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