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Assessing Aquatic Contamination from Tire Wear and Microplastics:Distribution Dynamics, Sampling Strategies, and Analytical Techniques
No full textPasteur:Scaling Privacy-aware Data Synthesis
No full textPrivacy-aware data synthesis is a field aiming to liberate data access through the generation of synthetic data which mirrors the original without resulting in privacy exposure. State-of-the-art algorithms for structured data perform well in datasets with tables of a few million rows but result in prohibitive runtimes when scaling to hundreds of millions of rows. In addition, due to the sensitive nature of data, practitioners are often limited to a single server environment. In thispaper, we present the framework Pasteur, which aims to scale privacy-aware data synthesis linearly under a single server environment. Pasteur achieves this through a parallelization approach tailored for synthesis, optimized memory representations, and an accelerated marginal calculation algorithm (bottleneck in a class of privacy-aware algorithms). We show Pasteur performing pre-processing, synthesis, and evaluation of a tabular dataset with 1 billion rows (200 GB) in 1 hour on a 16 core CPU server
Structural origin of disorder-induced ion conduction in NaFePO<sub>4</sub> cathode materials
No full textMost modern battery technologies depend on solid-state crystalline cathode materials. However, some of these materials are constrained by the low ionic conductivity of their most stable phases. An example of this is maricite (NaFePO4). Interestingly, experiments have shown that maricite can improve its rate capability through disordering (amorphization). However, experimental characterization of amorphous cathode materials remains a major challenge, hindering a clear understanding of the structural origin of the disorder-induced improvement in sodium-ion mobility. To address this, we here employ molecular dynamics simulations by first training a machine learning potential for NaFePO4 based on the atomic cluster expansion approach and a batch active learning potential parameterization scheme. This potential is then applied to explore the structural and dynamical properties of NaFePO4 glasses as cathode materials. Specifically, we investigate the effect of glass structure on sodium-ion diffusion, revealing the relative influences of short-range and medium-range order features. We find significant heterogeneity in sodium-ion diffusivity in the glass, with fast-conducting ions residing in less constrained atomic environments with fewer P and Fe neighbors. These more mobile ions are also surrounded by larger ring-type structures. Overall, the results and developed approach present promising avenues for developing high-performance glassy cathodes for next-generation batteries.</p
Rapid and selective detection of K+ in cigarette paper:The use of solid-contact polymer membrane electrodes based on ZnCo2O4-loaded hollow carbon nanospheres
No full textIn comparison to the classical liquid-contact ion-selective electrode (LC-ISE), the potential stability remains one of the major challenges currently faced by the solid-contact ion-selective electrode (SC-ISE). This challenge can be addressed by introducing a conducting layer between the conductive substrate and the polymer membrane to stabilize the potential output. In this paper, hollow carbon nanospheres loaded with zinc cobaltate nanoparticles (ZnCo2O4@HCNs) were synthesized by using a one-pot method, which served as an ion-electron conducting layer between the potassium ion-selective polymer membrane and the conductive glassy carbon substrate. Electrochemical impedance spectroscopy (EIS) and chronopotentiometry tests demonstrated a high capacitance and excellent potential stability for the solid-contact potassium ion-selective electrode (K+/SC-ISE). Water layer tests further confirmed that ZnCo2O4@HCNs exhibited strong hydrophobicity, effectively preventing the formation of water contact layers at the electrode/membrane interface, thereby ensuring a highly stable signal-response. Under the optimized conditions, the prepared K+/SC-ISE showed a good linear response in the concentration range of 1.0 × 10-6-1.0 × 10-2 mol/L with a Nernst slope of 56.03 ± 0.55 mV/decade. The detection limit was calculated to be 6.16 × 10-7 mol/L. Additionally, the electrode demonstrated excellent selectivity, stability, and a long lifetime of over 24 months. Finally, the electrode was successfully applied to the on-site detection of K+ in actual cigarette paper samples at the factory workshop, yielding results consistent with those using ion chromatography, highlighting its broad application prospect.</p
How local is decentral politics? Variations in the supply of municipal policies
No full textLocal democracy is theoretically based on political parties offering different policies across and within sub-national geographical units. However, local democracy is embedded within a multilevel party and institutional structure that may compromise this endeavour. This study develops three expectations of policy variation: within party variation in political positions across geographical units; differences in policy positions across parties within geographical units; and that parties adjust their supply of policy over time possibly based on structural, social, or party features. It is argued that the presence of these variations is important for local democracy considering multilevel party institutions and their existence is tested using 1,002 Danish municipal party election manifestos from the local elections in 2013 and 2017, covering all 98 Danish municipalities. The first two types of variation are clearly present, the third is only present between parties, and this suggests that local politics is at least somewhat local.</p
Improved wound healing by dual inhibition of miR-146a-5p and miR-29a-3p supports a network action of dysregulated miRNAs in diabetic skin
No full textAims/hypothesis: Upregulation of miR-146a-5p and miR-29-3p is observed in chronic non-healing wounds in diabetes. Their single or combined inhibition's molecular and cellular effects were assessed in human keratinocytes (HaCaT cells) and in vivo using a mouse model of type 1 diabetes. Methods: As primary outcomes, we screened for proteome changes in HaCaT cells by LC-MS/MS after transfection with miR-146a-5p or miR-29a-3p inhibitors individually or in combination and following stimulation with TNF-α. Moreover, as a secondary outcome, we collected the data and cryopreserved and paraffin-embedded skin biopsies to estimate the tissue response to miRNA inhibition using immunofluorescence and histological analysis. Cryopreserved biopsies were also used for the LC-MS/MS proteome profiling to identify targets and cellular pathways involved in observed tissue changes. Results: We identified a panel of extracellular matrix proteins, mainly laminins, whose levels changed after transfection with miR-146a-5p or miR-29a-3p inhibitors in HaCaT cells, counteracting TNF-α effects. There was a difference in wound closure rate in vivo between the dual inhibition of miR-146a-5p and miR-29a-3p and scramble controls on day 8 (p<0.01) and day 9 (p<0.05), although not at day 10. Histological analysis at day 10 shows a loose papillary layer in the scramble inhibition group, indicating incomplete wound closure compared with dual miRNA inhibition. Moreover, the dual action of the inhibitors decreased inflammation at day 3 and day 10 (both p<0.001) and reactive oxygen species formation (p<0.01) 3 days post wounding, while increasing the angiogenesis on day 3 (p<0.01) and day 10 (p<0.001). This was consistent with cytoskeletal rearrangements and collagen alterations observed in proteome profiling. Conclusions/interpretation: These findings demonstrate that dual inhibition of miR-146a-5p and miR-29a-3p in vitro synergises in a bidirectional manner, resulting either in intermediate effects or in cancelling each other’s activity for the levels of specific proteins of basal lamina that impair proliferation and cell motility, compared with the individual inhibitors. Topical supplementation of miR-146a-5p and miR-29a-3p inhibitors to diabetic mouse wounds resulted in a reduction in wound size on days 8 and 9, which correspond to the later stages of healing, but did not lead to complete healing by day 10. However, dual inhibition demonstrates favourable effects on high oxidative stress, elevated inflammation and poor angiogenesis. These effects are superior to single miRNA inhibition, suggesting that combined miRNA inhibition could be a promising therapeutic strategy for diabetic wound healing. Nevertheless, further studies in humans are warranted.</p
Occupants’ willingness to share information for improved comfort and energy efficiency in offices
No full textBackground: Human environmental perception and occupant behaviour are influenced by a multitude of factors, including demographic variables and individual preferences. Advancements in data collection allow the acquisition of extensive personal information, such as heart rate, skin temperature, and emotional responses to environmental conditions. These data can enhance research on multi-domain influences and on optimizing building operations but raise questions regarding individuals’ willingness to share personal information.Methodology:This study investigates how factors like data type, data collector, and anonymity level are associated with occupants’ willingness to share information for improved indoor environmental conditions or energy efficiency. A stated preference discrete choice experiment was developed and applied, with responses collected from participants in 29 countries, resulting in a dataset with 791 samples. The discrete choice analysis was conducted using mixed logit models and based on Random Utility Theory.Results:The outcomes indicate that respondents exhibit relative indifference toward sharing demographic and physical environmental data, while having heightened concerns about sharing psychological and activity-related information. Anonymity and control over the data appear to be of crucial importance. Additionally, data collection by academic institutions is preferred to that by for-profit entities. Variability in willingness to share data across and within samples of countries suggests a necessity for tailored strategies.Impact:This research underscores the necessity of balancing advancements in energy efficiency and thermal comfort with societal needs that respect individual rights. Practical recommendations for effective personal data collection are provided and methodological limitations due to scenario complexity and participant engagement are highlighted
Thermocatalytic ammonia synthesis beyond conventional Haber-Bosch: Principles, advances, challenges and opportunities
Get PDFTransforming ammonia (NH3) synthesis from the energy-intensive, fossil-fuel-dependent conventional Haber-Bosch (HB) process to a flexible, green hydrogen-based process is pivotal for decarbonization and enabling NH3 utilization in the energy sector. The conventional HB process, operating under high temperature and pressure, is incompatible with green hydrogen systems and economically unviable for downscaled NH3 production integrated with intermittent renewable energies . Therefore, developing alternatives capable of synthesizing NH3 under moderate conditions is crucial for achieving green NH3 production. This necessity has driven the development of a range of emerging technologies, including thermocatalytic, electrocatalytic, photocatalytic, and plasma-assisted processes, amongst which thermocatalysis stands out in terms of production rate, technology readiness, and economic feasibility, demonstrating the greatest potential for NH3 synthesis transformation. This review provides a comprehensive overview of advanced thermocatalytic NH3 synthesis beyond conventional HB process and the system integration with renewable sources. It highlights key limitations and advances in implementing new materials and auxiliary techniques, outlining the challenges and mitigation strategies for achieving high NH3 productivity under mild conditions. Alongside multiscale modeling studies, the review covers catalyst development, reactor intensification, process integration, and system evaluation, examining progress and conducting meta-analysis in reaction mechanisms, emerging separation technologies, and system integration. Scientific obstacles, economic analysis, and environmental impacts are thoroughly discussed, offering state-of-the-art insights into mild NH3 synthesis from fundamental research to practical applications. Additionally, recent industrial projects of green NH3 production are summarized, showcasing scalability and commercial viability. Finally, the remaining challenges and opportunities in advanced thermocatalytic NH3 synthesis are outlined, identifying future research frontiers.</p
Pathways of how health literacy and social support are associated with health outcomes in 17 European countries:Results of mediation analyses
No full textOBJECTIVES: To estimate and compare (1) how social support (SS) acts as a mediator for the association between health literacy (HL) and health outcomes, and (2) how HL acts as a mediator for the association between SS and health outcomes.STUDY DESIGN: Mediation analyses.METHODS: Data from the Health Literacy Survey 2019 (HLS19) were analyzed including 42,445 participants in 17 European countries. Four mediation models were tested with two health outcomes: self-reported health (SRH) and health-related limitations (Global Activity Limitations Indicator, GALI). In two models, SS was the mediator between HL and SRH and in the other two models HL was the mediator between SS and GALI.RESULTS: SS is a significant mediator of the association between HL and SRH in all countries and between HL and GALI in eight countries. Up to 25-30 % of the total effect was mediated by SS. In addition, HL is a significant mediator of the association between SS and SRH in 15 countries and between SS and GALI in eight countries. With regard to SRH, SS may be regarded as the more relevant mediator between HL and SRH; whereas for GALI, HL can be considered the mediating factor between SS and GALI, as the proportions mediated were higher in the respective models in most countries.CONCLUSIONS: Both HL and SS may serve as significant mediators in the models of both health measures, but to different extents. Planning interventions to mutually improve SS and HL may help communities improve health.</p
A secret radical enlightener in 1770s Copenhagen:Peter Frederik Suhm
No full textPeter Frederik Suhm was a historian and independent author in Denmark-Norway in the latter half of the eighteenth century. Mostly known for his extensive work as an author of historical works and fictions, he also developed a less known political doctrine through the 1760–70s, developing radical enlightenment ideas. These ideas culminated around the Danish Press Freedom Period 1770–3 and involved ideas such as freedom of speech and religion, rule of law, constitutional monarchy, an elected parliament, separation of powers, etc. — much of which were not or only partially published at the time. This paper investigates Suhm’s radical political philosophy.</p