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High H 2 production in sediment-hosted hydrothermal fluids at an ultraslow spreading mid-ocean ridge
Get PDFHydrothermal systems at ultraslow-spreading mid-ocean ridges remain poorly characterized, particularly where sedimentary and ultramafic influences intersect. Here we present geochemical analyses of vent fluids collected in 2024 from the Jøtul hydrothermal field on the northern Knipovich Ridge. Major element concentrations, dissolved gases, and thermodynamic modeling are used to investigate fluid-rock interactions. The fluids exhibit exceptionally high CH4 concentrations, that exceed those at the Guaymas Basin, and display characteristics typical of sediment-hosted hydrothermal systems, indicating thermal decomposition of organic matter in clastic sediments. In contrast, high H2 (>15 mM) and low H2S concentrations are more typical of ultramafic-hosted fluids, while geological evidence indicates that the vent field lies atop a detachment fault. Thermodynamic modeling suggests that these high H2/H2S ratios may result solely from degradation of organic matter followed by abiotic CH4 oxidation at ~400 °C, rather than from reactions with ultramafic rocks. These results expand the known diversity of sediment-hosted vent fluid compositions and highlight fluid-sediment interaction as an underestimated source of carbon and hydrogen
Mapping inequality in power law and exponential distributions
Get PDFWe present a theoretically grounded, entropy-based method for localizing inequality in probability distributions using recursive Hahn decomposition of an entropy-derived signed measure, while illustrating its applicability through examples drawn from physics and stochastic phenomena. Unlike traditional metrics that collapse entire distributions into single numbers, this method partitions the domain into regions of provably higher or lower uniformity, preserving monotonicity across recursive splits. Applied to two canonical distributions power law and exponential we obtain closed-form formulas for cutoff points and uniformity ratios. For power laws, these formulas reveal how inequality concentrates along heavy tails, replacing heuristic thresholds with analytic ones. For exponential distributions, including the Boltzmann form, we show that the entropy-based cutoff equals the conditional mean, giving it a new interpretation as an entropic equilibrium point where energy minimization and entropy maximization balance. This hierarchical decomposition moves beyond scalar summaries such as Gini or Theil, constructing a multiscale map of disparity that is both interpretable and computationally tractable. The approach generalizes to any continuous or discrete distribution, providing a unified, information-theoretic lens for analyzing inequality in economics, reliability theory, and statistical physics
The high-redshift radio galaxy 3C 294 at low frequencies: radio detection of the X-ray ghost
Get PDFWe report on the very first radio detection associated with the peculiar hourglass-morphology X-rays surrounding 3C 294 at . Using International Low Frequency Array (LOFAR) data at 144 MHz and Chandra data at 0.3–6 keV, we find that the co-spatial diffuse radio and X-ray emission is well described by synchrotron and inverse-Compton processes by the same electron population. Through modelling of this rare low-energy plasma, we find that the most defining property of the electrons up-scattering CMB photons at this redshift is very low electron Lorentz factors ( and ) in the lobe: deep low frequency ( MHz) observations are critical to the detection of radio lobes at high redshift. The physical conditions imply a total energy in the diffuse emission significantly greater than that implied by the temperature of the protocluster gas: 3C 294 is one of the most powerful known radio-loud systems in a dense protocluster environment. Through resolved spectral analysis of archival radio data up to 15 GHz, we find evidence that the inner hotspots are due to restarted activity, while the outer hotspots remain energetic, suggesting a rapid duty cycle while the jet precesses. This allowed the low-energy aged plasma driving the X-rays to remain spatially distinct from the high-energy plasma. Together, our results promise a revelation of active galactic nucleus-related radio emission at high redshift using future low-frequency arrays such as SKA-LOW
Event-Related Brain Potential Correlates of Face Processing: A High-Precision Replication and Individual Differences Study
No full textWhile substantial individual differences in face processing abilities are well established, their neural basis remains underexplored. Moreover, while recent years have seen an increased interest in highly powered replications of event-related potential (ERP) studies, experiments estimating ERP face processing effects with high precision are currently lacking. Here, we tested participants (N = 84) with a battery of standard (CFMT+, GFMT2) and purpose-built behavioral tests (response time priming), and measured several ERP effects (P100 contrast effect, N170 inversion and selectivity effects, image-independent N250r). Data were analyzed using both traditional component-based ERP analyses and data-driven mass univariate tests. We found highly reliable results for all face ERP effects, with medium to large effect sizes. Our results further suggest partly different neuro-cognitive processes underlying N170 inversion and selectivity effects, as well as early (N250r) and later ERP repetition effects. While participants with larger contrast effects in the P100 demonstrated better performance in both the GFMT2 and the CMFT+, N170 latency was related to the former and the N170 inversion effect to the latter test. Overall, these results provide high-precision estimates of ERP face processing effects and extend our knowledge on the neural basis of individual differences in face processing
Information on public opinion has lasting effects on second-order climate beliefs, but minimal and ephemeral effects on first-order beliefs
Get PDFAcross western democracies, pro-climate beliefs are widespread. Yet, vocal minorities contest scientific consensus about global warming. Perhaps as a consequence, the extent to which the public accepts global warming and climate action is often underestimated. Correcting this perceptual deficit has been proposed as a promising way to strengthen climate action, since knowledge of broad public consensus could motivate environmentally friendly behaviours, increase support for policy interventions, or shift perceptions of political feasibility. In a preregistered two-wave survey experiment in Germany, we provide a novel test of this strategy in a national context with already high pro-climate support, using real and comprehensive public opinion data. We find that exposure to this information can produce a lasting, significant increase in second-order beliefs (perceptions of public opinion) two weeks after treatment, especially among those who initially underestimated public support. However, the effects on first-order outcomes—policy feasibility perceptions, attitudes, and behavioural intentions—are small, short-lived, and largely non-significant. By demonstrating the boundary conditions of second-order interventions, our study suggests that their promise may be more limited than often assumed. These findings may highlight the potential need for more targeted, repeated, and context-sensitive approaches if second-order information is to meaningfully shift climate beliefs and behaviours
Improved convergence rates for the Hele-Shaw limit in the presence of confining potentials
Get PDFNowadays a vast literature is available on the Hele-Shaw or incompressible limit for nonlinear degenerate diffusion equations. This problem has attracted a lot of attention due to its applications to tissue growth and crowd motion modeling as it constitutes a way to link soft congestion (or compressible) models to hard congestion (or incompressible) descriptions. In this paper, we address the question of estimating the rate of this asymptotics in the presence of external drifts. In particular, we provide improved results in the 2-Wasserstein distance which are global in time thanks to the contractivity property that holds for strictly convex potentials
Tracking the trajectory of executive function from 2.5 to 6.5 years of age and the impact of COVID‐19
No full textGiven the significance of executive function (EF) for longer-term outcomes, it is important to understand the trajectory of EF in childhood and how COVID-19 influenced this trajectory. 139 (71 girls) children were examined longitudinally from 2.5 to 6.5 years using the Minnesota Executive Function Scale. Individual differences in EF abilities were stable longitudinally, and children with a more highly educated mother had higher EF scores. Children tested 1–3 years after the first lockdown showed greater variation in individual differences over time. Additional analyses examined linear growth curves for children assessed 3–4 times from 2.5 to 6.5 years. Children who were in preschool during the first lockdown had steeper growth curve trajectories than children in the first year of primary school
Outcome Assessment in Children and Adolescents With Chronic Pain: An International Clinical Practice Survey
No full textBackground: Effective treatment of paediatric chronic pain requires a robust and comprehensive set of outcome assessment tools to evaluate treatment effectiveness. Although a core outcome set (COS) exists for clinical trials, its practicability and appropriateness for clinical practice is currently unknown. This cross‐sectional study led by the IN‐ChildPain group aimed to: (1) identify clinical outcome domains and measures used by clinicians treating children and adolescents with chronic pain, (2) determine which domains are considered mandatory in clinical routine and (3) compare prioritisation across disciplines and countries. Methods: An online survey, available in eight languages, was conducted eliciting data from clinicians who treat children and adolescents with chronic pain. Percentages of the most commonly used outcomes were calculated, and z‐tests were performed to compare study variables based on participants' country income status and professional background. Results: A total of 193 clinicians from 42 countries participated. The most commonly assessed domains were pain intensity (84%), pain interference (80%) and physical functioning (79%), with higher assessment rates in high‐income countries. Pain intensity and interference were deemed mandatory by 93% of participants, followed by physical functioning (92%). However, only 53% reported using patient‐reported outcome measures, with the 0–10 Numeric Rating Scale being the most common (94%). Assessment practices varied as a function of country income level and professional background. Conclusions: The findings highlight the need to develop and implement a COS tailored to the needs and resources of clinicians. Such standardisation would enhance consistency in assessment, enable cross‐site benchmarking and promote equitable pain care globally. Significance: This study provides critical insights into how clinicians assess paediatric chronic pain, highlighting significant global disparities and professional differences in outcome domain prioritisation. By identifying commonly assessed domains, these findings emphasise the need for standardised measures and pave the way for developing a core outcome set tailored to clinical activities. Such an advance is essential for improving the consistency and quality of care for children and adolescents with chronic pain worldwide
Interventions for Preventing Obesity in Children and Adolescents Aged 5–18 Years: An Overview of Nonrandomized Study Evidence Reported in 28 Systematic Reviews
No full textIntroduction: Community‐ and population‐level and policy interventions are commonly evaluated using nonrandomized studies (NRS), rather than randomized trials (RCTs). Recent Cochrane reviews of interventions for preventing childhood obesity have been restricted to RCTs, so less is known about the effectiveness of these more upstream interventions. To address this gap, we conducted an overview of reviews of NRS interventions (NRSI), which assessed change in BMI in children and adolescents aged 5–18 years and compared NRSI findings with those from RCTs. Methods: We searched five databases up to November 2024. Screening, data extraction, and quality assessment were performed using standardized tools. Results: We included 28 systematic reviews and identified 136 NRSI either based in school (n = 118), community (n = 4) or combined settings (n = 14) and evaluating policy (n = 48), education (n = 11), or a combined intervention (n = 77). Twenty‐six reviews included both NRSIs and RCTs; of these, 12 reported meta‐analyses. Findings were largely unchanged when we excluded the RCTs and re‐ran analyses. Overall, study‐level results from the NRSI favored the intervention group; a quarter favored the comparison group. The meta‐analysis summary effects from NRSIs were consistent with two recently published Cochrane meta‐analyses of RCTs of obesity prevention interventions. Conclusions: The results from this overview of reviews suggest researchers and policy makers can be confident in considering the results of robust nonrandomized study designs (evaluating their impact on BMI) alongside RCTs in their decision making. Although we identified a significant number of NRSIs for review, very few evaluations of upstream interventions were eligible for inclusion
Establishment of environmental protection courts, green finance, and corporate operating performance
No full textBased on panel data from Chinese prefecture-level cities and listed companies from 2011 to 2023, this paper explores the relationship between the establishment of environmental protection courts (EEPC), green finance (GF), and corporate operating performance, and analyzes the moderating effect of GF on the relationship between EEPC and corporate operating performance. The research results indicate that, first, EEPC significantly enhances corporate operating performance. Secondly, the development of GF has a significant positive impact on corporate operating performance. In addition, GF plays a significant moderating role in the relationship between EEPC and corporate operating performance. Finally, the moderating effect of GF is more pronounced in high-pollution industries and large-scale enterprises. This paper provides theoretical support for policymakers promoting the development of EEPC and GF and offers empirical evidence for the formulation and optimization of related policies
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