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Development of a predictive model for PM2.5 over the greater Athens metropolitan area, Greece, at a 1 km by 1 km grid using satellite measurements and machine learning methods

Background Ambient PM 2.5 exposure is strongly associated with adverse health effects, including all-cause mortality. However, the lack of monitoring networks globally necessitates a better understanding of the spatiotemporal distribution of near-surface PM 2.5 pollution. While ground-level pollutants are traditionally measured at fixed stations, integrating land use and atmospheric reanalysis data captures the broad geospatial trends and specific aerosol compositions necessary for high-resolution exposure assessment. This study aims to demonstrate the accuracy and reliability of ensemble modeling for estimating near-surface PM concentrations at a high spatiotemporal resolution in Athens, Greece. Methods Daily PM 2.5 concentrations were estimated using a stacked ensemble machine learning model to incorporate distributed random forest, gradient boosting, and feedforward neural network algorithms to minimize predictive error compared to individual models. The input set for all base learners consisted of daily observations from air quality monitors between 2007–2019 combined with satellite-derived estimates, providing a total of 61 variables describing regional aerosol, weather, and land use characteristics. Results We observed strong predictive performance in our ensemble model, with a mean R 2 of 0.85 and an average error of 4.18 μg/m 3 . The annual average concentration of PM 2.5 (22.30 μg/m 3 ) exceeded current WHO and EU guidelines, with considerable spatiotemporal variation across greater Athens. The highest annual mean PM 2.5 concentrations were in 2007 (33.18 μg/m 3 ) and on average year-to-year, PM 2.5 concentrations were highest during the mid-winter months, in agreement with the expected seasonal maximum for the region, likely driven by increased residential heating alongside winter meteorological conditions, such as temperature inversions and a shallow, stable planetary boundary layer. Significance This is among the first studies to estimate PM 2.5 exposures in the greater Athens region at a high spatiotemporal resolution using diverse satellite and land use data. This framework enables the investigation of cumulative exposures, particularly in regions with limited ground-level monitoring.

Objects with three orthogonal symmetry planes: Oblique driving forces and Stokes flow motion

Stokes flow studies are fundamental to advancing medical and industrial technologies, particularly in areas such as drug targeting, cell studies, the optimization of drug carrier vehicles, high viscosity flows, and magnetic particle imaging. While previous research has focused on the motion of obliquely falling cylindrical rods and magnetic particle chains, a broader analytical framework is required to understand more complex particle-fluid migrations. In this paper, we first generalize the two-dimensional motion of an obliquely falling rod in a gravitational field to the three-dimensional motion of an object possessing three mutually perpendicular planes of symmetry falling through a viscous fluid in the Stokes limit. We derive a general formula for the three components of velocity—including both downward and sideways components—for objects of arbitrary orientation and uniform density. These analytical solutions are defined in terms of the object’s orientation, specified via Euler angles, and the velocity of the object falling along each of its three principal axes, or the drag coefficient along each of those axes. We give a variety of examples of objects that satisfy this general formula. In addition, we apply the formula to a cuboid for which those velocity components along each of its principal axes have been measured experimentally by other researchers, thus giving both the downward and sideways components for arbitrary orientation. We then analyze the motion in a gradient magnetic field of elongated magnetic particles, such as nanorods and nanoellipsoids, for which the induced magnetic moment is along the long axis of the particle. We discuss the similarities and differences with the gravitational case. By providing a unified framework for predicting the trajectories of these symmetric bodies, this work enhances the understanding of the motion of inertial and magnetic particles under the influence of gravitational and gradient magnetic fields, respectively.

Correction: Hsa-mir-3163 and CCNB1 may be potential biomarkers and therapeutic targets for androgen receptor positive triple-negative breast cancer

Longitudinal changes and risk factors of Opisthorchis viverrini infection after selective praziquantel treatment: evidence from urine antigen assay and fecal examination in an endemic community in Northeast Thailand

Opisthorchis viverrini infection remains an important public health problem in Southeast Asia, particularly among rural populations in Northeast Thailand. Despite control efforts, transmission remains uninterrupted due to persistent behavioral and environmental factors. To better understand the longitudinal patterns of opisthorchiasis after selective praziquantel treatment, this study aimed to determine the incidence and reinfection rates in the study population and identify risk factors associated with O. viverrini infection. Based on a prospective study, the status of opisthorchiasis was monitored in a cohort of participants (n = 612) in Northeast Thailand using the formalin-ethyl acetate concentration technique (FECT) and O. viverrini antigen detection in urine by Enzyme-linked immunosorbent assay (ELISA). The baseline prevalence of O. viverrini infection was 41.0% by urine antigen assay, compared to 8.1% by FECT. Over the 24-week study period, the calculated incidence of infection was 64.6/100 person-years, and the reinfection rate after PZQ treatment, as measured by urine ELISA, was 63.7/100 person-years. Based on FECT, a tenfold lower incidence (7.5/100 person-years) and reinfection rate (5.9/100 person-years) were observed. Risk factor analysis identified raw fish consumption in the previous 6 months (aRR = 7.52; p < 0.001), frequent raw fish consumption (>10 times per month) (aRR = 3.60; p < 0.001), and previous praziquantel treatment aRR = 1.49; p = 0.032) as significant risk factors for infection. The results demonstrated that the persistence of opisthorchiasis prevalence is driven mainly by the incidence of infection and reinfection after chemotherapy, as assessed by urine antigen assay and FECT. Behavioral risk factors, particularly the consumption of raw fish, remain the primary risk of parasite transmission. Therefore, comprehensive intervention measures consisting of sensitive diagnostics, drug treatment, and culturally appropriate interventions are required.

Sports tourism motivation and tourist satisfaction in resort Ski tourism: A distal mediation model of tourist expectation and experience quality

The popularity of leisure skiing culture presents a paradox with declining visitor satisfaction, and this study aimed to elucidate the mechanisms influencing tourist satisfaction in leisure ski tourism through a distal mediation model. Data were collected from 302 valid samples at Changbaishan Wanda International Ski Resort within the Changbaishan National Reserve in Jilin Province, Northeast China, using mixed offline-online methods. Structural equation modeling was conducted via IBM SPSS Statistics and AMOS 26.0, utilizing maximum likelihood estimation combined with Bollen-Stine bootstrap for hypothesis testing. While direct effects confirmed all hypotheses except hypothesis 5, results further revealed significant positive mediating effects: sport tourism motivation exhibited a distal mediation effect on tourist satisfaction through tourist expectation and experience quality and an independent mediation effect through experience quality alone. These findings collectively demonstrate that tourist expectation and experience quality mediate the relationship between motivation and satisfaction in leisure skiing contexts.

Correction: Implementing the Lung Donor (LUNDON) acceptability score in U.S. donor management and transplant decision-making: A multi-aim, mixed-methods protocol

Improving outcomes of patients living with psoriatic arthritis: The Observational Best Practices Research Initiative (OBRI-PsA) registry: Rationale, Methodology and Preliminary Data of 18 Months Follow-up

Objectives Psoriatic arthritis (PsA) is a heterogeneous, chronic inflammatory disease with diverse musculoskeletal and extra-articular manifestations, including enthesitis and dactylitis, which contribute substantially to disease burden, disability, and poor quality of life. Therapeutic advances have mainly focused on polyarticular disease, with limited representation of other PsA domains and real-world complexity. The Observational Best Practices Research Initiative for Psoriatic Arthritis (OBRI-PsA) was established as a national registry to systematically capture diverse PsA phenotypes, assess real-world treatment patterns, and longitudinal clinical outcomes. This report describes the registry methodology and presents preliminary findings from the initial enrolled cohort. Methods OBRI-PsA is actively enrolling patients with active PsA initiating new disease-modifying therapy, irrespective of domain or burden. Baseline and follow-up data are systematically collected to evaluate treatment responses, patient-reported outcomes, productivity, and real-world strategies. Descriptive analyses of 18-month outcomes from the first 101 enrolled patients are presented as a proof-of-concept; the full study protocol is available in the supplementary material. Results As of September 2024, a total of 101 patients were enrolled (mean age 53.9 ± 12.7 years; 61.4% female). Symmetrical polyarthritis predominated (86.1%), with 91% having skin psoriasis, 49% enthesitis, and 42% dactylitis. At baseline, mean tender and swollen joint counts were 9.8 and 6.5. Over 18 months, patient- and physician-reported outcomes improved, yet only one-third achieved minimal disease activity (MDA). Response rates varied across domains, with the lowest rate observed for enthesitis (24%). Most patients (60–74%) remained on the same therapy at follow-up with no further modifications, despite ongoing disease activity. Patients with fibromyalgia reported higher disease activity, lower quality of life, and fewer treatment responses. Conclusion Preliminary data from OBRI-PsA highlight persistent unmet needs and variable treatment responses across PsA phenotypes in real-world practice, with relatively few patients achieving treatment targets. These early signals underscore the importance of a comprehensive, longitudinal registry platform to better characterize disease heterogeneity and to inform future phenotype-driven, outcome-focused analyses.

Correction: Integrating psychosocial health into disaster risk management: Insights from COVID-19 in Durán, Ecuador

Role of Water in Low‐Temperature CO ₂ Reduction at Defect‐Rich TiO ₂

ABSTRACT Point defects in titanium dioxide (TiO 2 ) are the most relevant reaction sites for the activation of oxygenates. Herein, we probe the activation of CO 2 on highly defective TiO 2 in situ using synchrotron‐based near‐ambient pressure X‐ray photoelectron spectroscopy between 0.1 mbar and 2.6 mbar from room temperature to 700 K. Multiple carbon surface intermediates form upon CO 2 activation. The presence of key intermediates acts as a fingerprint for the population of different reaction pathways, that is, promotion or suppression of selected reaction steps in various gas environments. In the absence of potent H/OH donors, the formyl, glyoxal, formaldehyde and carbene pathways are populated simultaneously. However, aqueous atmospheres boost intermediate formation and promote oxygen‐rich organic molecules, suppressing coke formation along the carbene pathway. Thermal loss of hydroxyls above ≈550 K triggers the population of such oxygen‐lean routes, along with a decrease in carbon intermediates, converging to the chemistry under water‐free conditions. Our results highlight reduced titania as a noble metal‐free CO 2 activation catalyst and demonstrate how water can be used to favor the desired product distribution. The findings herein will guide the development of sustainable catalysts from heavily reduced oxides, for example, black titania, for platform chemicals based on CO 2 as a building block.

Research on passenger-train coordination and passenger flow evolution in Urban rail transit systems under degraded operations

Under degraded operations in urban rail transit systems, the coordinated state between passengers and trains undergoes significant changes due to factors such as train frequency reduction. This creates a critical mismatch between passenger demand and transport capacity, leading to rapid passenger accumulation at stations and potential safety hazards from abnormal crowding and systemic congestion. This study develops an integrated simulation model that combines train schedules with passenger arrival patterns to quantify how altered departure sequences generate supply-demand imbalances. A bounded rationality route choice model incorporating four decision-making dimensions – time value, transfer burden, service degradation impact, and route familiarity – captures passenger behavioral adaptations during degraded operations. The experimental results indicate that under abnormal train operation scenarios, the model incorporating bounded rationality assumptions is closer to actual observed values compared with the fully rational benchmark model. In the L2 degradation scenario, the deviation between the bounded rationality model and the actual values is controlled within 0.6%–1.3%, whereas the deviation of the fully rational model is approximately 12%. Concurrently, passenger flow propagation intensity in core sections rises from 0.3 to 0.7, showing a clear evolution from localized accumulation to regional diffusion. The research provides an effective methodology for identifying passenger flow dynamics under degraded operational scenarios and supports decision-making for service optimization and passenger flow management.

Enzymatic Encoding of Topology in an Intrinsically Disordered Single‐Chain Protein

ABSTRACT Controlling the three‐dimensional topology of single‐chain nanoparticles (SCNPs) remains a central challenge in polymer and protein chemistry, particularly for intrinsically disordered systems lacking defined secondary structure. Here, we demonstrate that selective enzymatic intramolecular cross‐linking can encode topologically biased interactions in an intrinsically disordered protein (IDP), yielding compact SCNPs with reproducible cavity architecture. Using β‐casein‐rich sodium caseinate (βNaCn) as a model surrogate for bovine β‐casein (β‐Cn), microbial transglutaminase (mTGase) introduces sparse, sequence‐resolved glutamine‐lysine isopeptide bonds that drive reproducible chain collapse without inducing secondary structure. Analyses by size exclusion chromatography with quintuple detection (SEC‐D5), cross‐linking mass spectrometry (XL‐MS), molecular dynamics (MD) simulations, and SEC coupled to synchrotron small‐angle x‐ray scattering (SEC‐SAXS) converge to reveal a topology combining a stable, compact, hydrophobic core with flexible, disordered loops. These cavities are probed using Nile red (NR) fluorescence and SEC‐SAXS, which together provide topology information via guest‐induced density redistribution after NR capture. This work establishes that sparse enzymatic constraint installation, combined with residue‐resolved cross‐link mapping and orthogonal structural analysis, can encode and validate topology in a disordered single chain, thereby placing IDP‐like covalent folding in direct conceptual continuity with SCNP design.

Electroenzymatic CO ₂ Fixation

ABSTRACT Replacing fossil resources with renewable alternatives for chemical production requires highly integrated, energy‐efficient, and selective CO 2 utilization processes. Electroenzymatic CO 2 fixation offers a promising pathway, combining high energy efficiency with unparalleled product selectivity, making it a viable approach for synthesizing complex molecules. This review outlines the fundamental principles of bioelectrocatalytic CO 2 conversion using reductases and carboxylases, providing an overview of the available enzymes, their product range, and key thermodynamic and kinetic considerations. By highlighting both the potential and limitations of electrochemical CO 2 fixation, this review aims to inform future progress in the discovery, engineering, and application of CO 2 ‐converting enzymes, with the ultimate goal of realizing the full potential of electroenzymatic CO 2 fixation for the sustainable synthesis of fine and specialty chemicals.

Associations between ambient air pollution and mortality during a 7-year ecological time-series study

Effect of early skin-to-skin contact after vaginal birth on neonatal stress and day-5 bilirubin levels: a randomized trial

Generalized Analysis of Electrophilic Small Molecules

ABSTRACT Chemical construction almost universally employs highly customized product‐specific analytics. A transition toward generality will remove this critical bottleneck. Here we present how the fundamental chemical property of electrophilicity can be leveraged to generalize reaction analytics. By using a simple thiol probe we transform customized analytical schemes for electrophilic small molecules into a single generalized readout by tandem mass spectrometry. We apply this strategy to acrylamides commonly found in covalent inhibitors, and subsequently show how it can be extended to other classes of electrophilic small molecules. Application of this approach to high‐throughput chemical synthesis streamlines analysis, enabling rapid readouts of chemical analogs featuring acrylamides.

Long-term trajectories of social adjustment and emotional/behavioral problems in pediatric post-acute COVID-19

Molecular Qubits for Anion Sensing by Tuning Electron Spin Relaxation via Axial Ligand Field

ABSTRACT Previously, we reported a new macrocyclic ligand, Mes N 6 , which enables the room‐temperature coherence of Cu( Mes N 6 )(OTf) 2 . In this study, we characterize a new series of complexes based on the square planar [M( Mes N 6 )] 2+ motif with different anions, X, (M = Co, Cu; X = SiF, OTf, and Cl) to tune the electron spin relaxation properties of Cu(II) and Co(II) through changes to the axial ligand. For Cu(II), a weakly‐coordinating SiF counterion minimizes orbital angular momentum (OAM) and prolongs longitudinal relaxation. An inverted trend is observed for Co(II) where a more donating Cl axial ligand decreases OAM and prolongs spin relaxation. The most pronounced effect occurs when the singly‐occupied molecular orbital (SOMO) is and its energy is most significantly impacted by anion binding. Using changes in coordination of Co(II) we detect chloride anions at 125 µM (0.25 equivalents) through relaxometry as measurable differences in longitudinal spin relaxation (T 1 ). Additionally, chloride coordination enables T m ‐based detection by Hahn echo of a Co(II)‐chloride species. Overall, we demonstrate predictable changes to electron spin relaxation through systematic variation of the axial ligand field, providing a strategy for molecular quantum sensing of anionic ligands.

Author Correction: Fractal nature of galaxy clustering in the updated CfA redshift catalog

Daily briefing: World Cup ‘hydration breaks’ miss the mark

Cross-domain microbial differences across freshwater and marine habitats in a tropical delta

Abstract Microbial communities are central to aquatic ecosystem functioning, yet integrated cross-domain comparisons of prokaryotic and microeukaryotic microbiomes remain underexplored in tropical regions, particularly in Bangladesh. Here, we investigated habitat-associated differences in microbial community structure across freshwater and marine ecosystems of the Bangladesh tropical delta using 16S and 18S rRNA gene amplicon sequencing and assessed inferred functional potential for prokaryotic communities. Six freshwater and ten seawater samples were analyzed, comprising eight newly generated datasets (six freshwater and two seawater) and eight previously published seawater datasets. Prokaryotic communities exhibited significantly higher alpha diversity in freshwater, whereas microeukaryotic diversity showed no significant habitat-associated differences after correction, despite a weak freshwater enrichment trend. Beta diversity revealed clear compositional separation between habitats for both domains, with prokaryotes exhibiting centroid shifts and microeukaryotes showing greater within-group dispersion. Taxonomic profiles showed seawater dominance by Gammaproteobacteria and Alphaproteobacteria, whereas freshwater communities were more evenly distributed across Bacteroidota, Actinomycetota, and Verrucomicrobiota. Microeukaryotic assemblages also displayed pronounced habitat-associated restructuring. Functional inference of prokaryotic communities indicated conservation of core pathways across habitats despite taxonomic turnover. Exploratory cross-domain correlation analysis identified mixed positive and negative associations, although none remained significant after multiple-testing correction. Collectively, these findings reveal consistent habitat-associated microbial differentiation across tropical freshwater and marine ecosystems and provide a comparative baseline for understanding cross-domain microbial biogeography in climate-sensitive aquatic environments.