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Observational evidence linking loop length and thermal–nonthermal peak timing in solar flares
Full text linkWe investigate how the magnetic loop length of solar flares relates to the timing between their thermal and nonthermal emission signatures. Our study analyzes a sample of 96 C-, M-, and X-class flares observed between 2013 and 2015 with soft X-rays, hard X-rays, and extreme UV. For each event, we determine the time delay Δ t between the hard X-ray and soft X-ray peak, and estimate the flare loop length L from UV footpoints assuming a semicircular geometry. In every case, longer flare loops are consistently associated with larger timing delays. Across the full sample, we find a strong correlation R = 0.88 between L and Δ t . We also quantify how closely each flare follows the Neupert effect using a coefficient R N , defined as the Pearson correlation between the time derivative of the soft X-ray flux and the hard X-ray light curve. Applying correlation thresholds of R N ≥ 0.5 and R N ≥ 0.8 yields subsets of 87 and 46 events, respectively. In both cases, the linear relationship between loop length and peak delay remains clearly expressed. For the R N ≥ 0.5 subset, the correlation is R = 0.87, while the more selective subset with R N ≥ 0.8 displays an even stronger correlation of R = 0.91. These results show that the overall trend persists across increasingly stringent correlation thresholds. The results provide direct observational confirmation that magnetic loop geometry plays a key role in governing the temporal evolution of energy transport in solar flares
Upstream interventions to promote oral health and reduce oral health inequalities: a scoping review
No full textObjectives:
This scoping review aimed to map global evidence on upstream interventions which promote oral health and reduce socioeconomic inequalities in oral health.
Methods:
A review was undertaken in accordance with the Joanna Briggs Institute (JBI) methodology for scoping reviews and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews (PRISMA-ScR) checklist. A multistranded comprehensive search strategy was employed to identify relevant studies. Article texts were retrieved and assessed for eligibility against the inclusion criteria. Key findings were extracted and summarised.
Results:
A total of 99 articles (74 empirical studies and 25 systematic, scoping and umbrella reviews) were included in the scoping review. The review findings revealed a limited number of upstream interventions specifically focused on promoting oral health and reducing oral health inequalities. Legislative and regulatory measures (e.g., advertising controls), fiscal measures (e.g., sugar-sweetened beverage taxation) and specific oral health interventions (e.g., water fluoridation) have shown a positive impact on promoting oral health. In addition, fiscal measures, food subsidies targeted at low-income groups and improvements to housing/work environments have proven effective in reducing socioeconomic inequalities in general health outcomes.
Conclusions:
Despite a very detailed and thorough search of the global literature, this scoping review identified a limited number of upstream interventions that specifically focused on improving oral health, and an even smaller number of upstream interventions that tackled oral health inequalities. However, the review did identify three levels of upstream intervention including: policies tackling the broader socio-political determinants of health; policies combating non-communicable diseases (NCDs) linked to oral health; and some specific interventions (e.g., water fluoridation) focusing on oral health. The upstream approach to prevention remains highly relevant to public health policy and provides a guiding principle for future strategic action to promote oral health and tackle oral health inequalities
Estimating the placebo effect on patient-reported outcomes in sham-controlled device trials: insights from REDUCE LAP-HF II
No full textBACKGROUND:
Patient-reported outcomes are increasingly used as end points in clinical trials. However, the magnitude of observed changes in control arms attributable to placebo effects, as compared with other benefits of trial participation, has not been described. This study seeks to estimate the magnitude of the placebo effect by calculating changes in Kansas City Cardiomyopathy Questionnaire Overall Summary (KCCQ-OS) scores, which quantify the impact of heart failure on patients’ symptoms, function, and quality of life, after participants were unblinded to treatment.
METHODS:
REDUCE LAP-HF II (Reduce Elevated Left Atrial Pressure in Patients With Heart Failure II) randomized participants to atrial shunt or sham procedure, with unblinding after 2 years. The KCCQ was collected at baseline, 2, and 3 years after randomization. KCCQ-OS change from baseline to 2 years (placebo effect plus other benefits from trial participation) and the change from 2 to 3 years (placebo effect loss after unblinding) were calculated in sham-treated patients using mean±SD, as were changes from 2 to 3 years in shunt-treated patients (placebo effect benefit).
RESULTS:
The analytic cohort included 421 participants (median age, 72 years; 65.6% female). Among sham-treated participants (N=182), the mean±SD KCCQ-OS 2-year improvement from baseline was +9.3±22.4 points, with a decrement after unblinding of −1.7±18.2 points from 2 to 3 years. Among shunt-treated patients (N=239), mean±SD KCCQ-OS 2-year improvement was +12.7±22.8 points, with an improvement after unblinding of +1.9±18.2 points. In a hypothetical unblinded trial where placebo effect benefit would be expected in the active intervention arm, and none in the untreated arm, the combined effects would be 3.6 points.
CONCLUSIONS:
In a sham-controlled device trial that collected patient-reported outcome data during blinded allocation to treatment or sham and after unblinding, the estimated mean placebo effect benefit and loss on the KCCQ-OS were small (≤2 points). Finding a modest placebo effect on patient-reported outcomes may increase confidence in their use as clinical trial outcomes
Mitigating natural hazards through optimization of China’s Ecological Conservation Redline: a case of Zhejiang Province
No full textNatural hazards pose significant threats to human societies. Nature-based solutions (NbS) have emerged as a promising approach to address these challenges. China’s Ecological Conservation Redline (ECR) policy, which aims to safeguard ecosystem integrity and connectivity, provides a powerful framework for applying NbS. However, previous studies have paid little attention to the role of ECR in mitigating natural hazards. This study investigates how to optimize the ECR for mitigating natural hazards in Zhejiang Province, China. Using a “hazard formation, ecosystem response, NbS governance” framework, the research assesses multi-hazard susceptibility, identifies ecosystem services (ES) conservation priority areas, and ultimately optimizes the ECR pattern. The MaxEnt model was employed to evaluate hazard susceptibility, while the Ordered Weighted Averaging method was used to overlay different ES scenarios to determine conservation priorities. The results indicate that high-risk areas for collapse, mudslide, and landslide are predominantly located in the western and southern mountainous regions of Zhejiang, with the multi-hazard integration showing that high-risk areas cover 17.67% of the total land area. We set up 11 scenarios with varying risk values, showing that as risk values increase, the extent of conservation priority areas generally expands and overlaps more with ECR areas. Based on the comprehensive analysis, the scenario offering the optimal balance between ES conservation and hazard mitigation efficiency was selected to optimize the ECR, improving the ECR’s protective coverage of hazard-prone areas from 17.97% to 38.55%. Optimizing ECR through the NbS approach can effectively contribute to risk management while providing policy enlightenment to Territorial Spatial Planning
Pore-scale synchrotron imaging of scCO2-brine intermittent flow: experimental insights into multiphase dynamics for geological carbon storage
Full text linkUnderground carbon dioxide (CO2) storage is a critical approach for mitigating climate change by sequestering CO2 in deep geological formations. The interaction between injected super critical (sc) CO2 and resident brine within pores results in complex two-phase flow dynamics that influence the efficiency and security of storage. While previous studies have mainly focused on capillary-dominated regimes, where fluid phases flow at low velocities, the transitional intermittent flow regime—characterised by higher flow rates and complex displacement dynamics—remains less understood. This study investigates the onset and development of intermittent flow pathways in CO2-brine systems through high-resolution synchrotron X-ray micro-computed tomography imaging of a carbonate rock sample. The core-flooding experiments were conducted under 8 MPa and 50 °C to examine pore-scale fluid configuration changes as a function of capillary number (Ca). The results indicate that intermittent flow emerges at lower Ca values than previously observed in oil-brine systems, with a distinct transition from Darcy flow to intermittent flow. Moreover, the saturation of the intermittent phase stabilises beyond a threshold Ca, suggesting another phase transition within the intermittent flow regime. These findings provide new insights into the fundamental mechanisms of two-phase flow dynamics at the pore scale, revealing a stable intermittent flow regime at higher flow rates, with potential implications for improved injectivity under non-equilibrium conditions
Capitalismo dopaminergico
No full textL’economia della crescita sfrutta i nostri limiti cognitivi per mantenersi in vita. Comprendere come funziona il nostro cervello è il primo passo per rompere il circolo vizioso. Una conversazione con Matteo Motterlin
What training do workplace mentors receive to support degree apprentices? An activity theory analysis, focusing on inclusion
Full text linkWorkplace mentors play a crucial role in supporting degree apprentices, as guides and advocates in the workplace and partners in the tripartite meetings with the university. The mentor can help to facilitate relevant work-based opportunities and identify appropriate credit-bearing workplace projects. So, it is in the interest of the university to provide the mentor with appropriate information and training. This study aimed to establish the current mentor training context within computing apprenticeship degrees in UK universities, with a specific focus on training to support inclusion. Two online surveys gathered the perspectives of workplace mentors (n = 44) and of university staff providing training (n = 13). A review of guidance materials provided to mentors by universities triangulated the picture. Activity theory (AT) facilitated a new way of exploring current training systems to include the actors and influences beyond the immediate collaboration. The main finding is that few mentors felt they were receiving adequate training for the role, with many not receiving any, representing a lost opportunity to learn and share knowledge. The AT analysis highlighted the challenges of ringfencing time for mentoring and allocating responsibility for appropriate training and inclusion strategies among the collaboration partners
Mixed finite element method for device simulations
Full text linkThis paper presents a new numerical approach for simulating semiconductor devices using the Mixed Finite Element Method (Mixed FEM). Compared to the standard finite element method, Mixed FEM enables a more accurate treatment of material discontinuities, resulting in improved carrier density simulation across heterogeneous interfaces. Our main contribution is the implementation of Mixed FEM for semiconductor equations involving heterogeneous material interfaces, using the open-source, parallel finite element library MoFEM, thereby providing an extensible platform for future research. In particular, the Mixed FEM formulation results in a specific block-matrix structure that is compatible with GPU acceleration, paving the way for efficient large-scale device simulations
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