Indoor air quality in subway microenvironments: Pollutant characteristics, adverse health impacts, and population inequity.

Rapidly increasing urbanization in recent decades has elevated the subway as the primary public transportation mode in metropolitan areas. Indoor air quality (IAQ) inside subways is an important factor that influences the health of commuters and subway workers. This review discusses the subway IAQ in different cities worldwide by comparing the sources and abundance of particulate matter (PM2.5 and PM10) in these environments. Factors that affect PM concentration and chemical composition were found to be associated with the subway internal structure, train frequency, passenger volume, and geographical location. Special attention was paid to air pollutants, such as transition metals, volatile/semi-volatile organic compounds (VOCs and SVOCs), and bioaerosols, due to their potential roles in indoor chemistry and causing adverse health impacts. In addition, given that the IAQ of subway systems is a public health issue worldwide, we calculated the Gini coefficient of urban subway exposure via meta-analysis. A value of 0.56 showed a significant inequity among different cities. Developed regions with higher per capita income tend to have higher exposure. By reviewing the current advances and challenges in subway IAQ with a focus on indoor chemistry and health impacts, future research is proposed toward a sustainable urban transportation systems.

Assessing the Impact of Non-Exhaust Emissions on the Asthmatic Airway (IONA) Protocol for a Randomised Three-Exposure Crossover Study.

BACKGROUND: People living with asthma are disproportionately affected by air pollution, with increased symptoms, medication usage, hospital admissions, and the risk of death. To date, there has been a focus on exhaust emissions, but traffic-related air pollution (TRAP) can also arise from the mechanical abrasion of tyres, brakes, and road surfaces. We therefore created a study with the aim of investigating the acute impacts of non-exhaust emissions (NEEs) on the lung function and airway immune status of asthmatic adults. METHODS: A randomised three-condition crossover panel design will expose adults with asthma using a 2.5 h intermittent cycling protocol in a random order at three locations in London, selected to provide the greatest contrast in the NEE components within TRAP. Lung function will be monitored using oscillometry, fractional exhaled nitric oxide, and spirometry (the primary outcome is the forced expiratory volume in one second). Biomarkers of inflammation and airborne metal exposure will be measured in the upper airway using nasal lavage. Symptom responses will be monitored using questionnaires. Sources of exhaust and non-exhaust concentrations will be established using source apportionment via the positive matrix factorisation of high-time resolution chemical measures conducted at the exposure sites. DISCUSSION: Collectively, this study will provide us with valuable information on the health effects of NEE components within ambient PM2.5 and PM10, whilst establishing a biological mechanism to help contextualise current epidemiological observations.

PM10-bound trace elements in pan-European urban atmosphere.

Although many studies have discussed the impact of Europe's air quality, very limited research focused on the detailed phenomenology of ambient trace elements (TEs) in PM10 in urban atmosphere. This study compiled long-term (2013-2022) measurements of speciation of ambient urban PM10 from 55 sites of 7 countries (Switzerland, Spain, France, Greece, Italy, Portugal, UK), aiming to elucidate the phenomenology of 20 TEs in PM10 in urban Europe. The monitoring sites comprised urban background (UB, n = 26), traffic (TR, n = 10), industrial (IN, n = 5), suburban background (SUB, n = 7), and rural background (RB, n = 7) types. The sampling campaigns were conducted using standardized protocols to ensure data comparability. In each country, PM10 samples were collected over a fixed period using high-volume air samplers. The analysis encompassed the spatio-temporal distribution of TEs, and relationships between TEs at each site. Results indicated an annual average for the sum of 20 TEs of 90 ± 65 ng/m3, with TR and IN sites exhibiting the highest concentrations (130 ± 66 and 131 ± 80 ng/m3, respectively). Seasonal variability in TEs concentrations, influenced by emission sources and meteorology, revealed significant differences (p < 0.05) across all monitoring sites. Estimation of TE concentrations highlighted distinct ratios between non-carcinogenic and carcinogenic metals, with Zn (40 ± 49 ng/m3), Ti (21 ± 29 ng/m3), and Cu (23 ± 35 ng/m3) dominating non-carcinogenic TEs, while Cr (5 ± 7 ng/m3), and Ni (2 ± 6 ng/m3) were prominent among carcinogenic ones. Correlations between TEs across diverse locations and seasons varied, in agreement with differences in emission sources and meteorological conditions. This study provides valuable insights into TEs in pan-European urban atmosphere, contributing to a comprehensive dataset for future environmental protection policies.

Remote rhythm monitoring using a photoplethysmography smartphone application after cardioversion for atrial fibrillation.

Aims: Direct current cardioversion (DCCV) is a commonly utilized rhythm control technique for atrial fibrillation. Follow-up typically comprises a hospital visit for 12-lead electrocardiogram (ECG) two weeks post-DCCV. We report the feasibility, costs, and environmental benefit of remote photoplethysmography (PPG) monitoring as an alternative. Methods and results: We retrospectively analysed DCCV cases at our centre from May 2020 to October 2022. Patients were stratified into those with remote PPG follow-up and those with traditional 12-lead ECG follow-up. Monitoring type was decided by the specialist nurse performing the DCCV at the time of the procedure after discussing with the patient and offering them both options if appropriate. Outcomes included the proportion of patients who underwent PPG monitoring, patient compliance and experience, and cost, travel, and environmental impact. Four hundred sixteen patients underwent 461 acutely successful DCCV procedures. Two hundred forty-six underwent PPG follow-up whilst 214 underwent ECG follow-up. Patient compliance was high (PPG 89.4% vs. ECG 89.8%; P > 0.999) and the majority of PPG users (90%) found the app easy to use. Sinus rhythm was maintained in 71.1% (PPG) and 64.7% (ECG) of patients (P = 0.161). Twenty-nine (11.8%) PPG patients subsequently required an ECG either due to non-compliance, technical failure, or inconclusive PPG readings. Despite this, mean healthcare costs (£47.91 vs. £135 per patient; P < 0.001) and median cost to the patient (£0 vs. £5.97; P < 0.001) were lower with PPG. Median travel time per patient (0 vs. 44 min; P < 0.001) and CO2 emissions (0 vs. 3.59 kg; P < 0.001) were also lower with PPG. No safety issues were identified. Conclusion: Remote PPG monitoring is a viable method of assessing for arrhythmia recurrence post-DCCV. This approach may save patients significant travel time, reduce environmental CO2 emission, and be cost saving in a publicly-funded healthcare system.

A multispecies hierarchical model to integrate count and distance-sampling data.

Integrated community models-an emerging framework in which multiple data sources for multiple species are analyzed simultaneously-offer opportunities to expand inferences beyond the single-species and single-data-source approaches common in ecology. We developed a novel integrated community model that combines distance sampling and single-visit count data; within the model, information is shared among data sources (via a joint likelihood) and species (via a random-effects structure) to estimate abundance patterns across a community. Parameters relating to abundance are shared between data sources, and the model can specify either shared or separate observation processes for each data source. Simulations demonstrated that the model provided unbiased estimates of abundance and detection parameters even when detection probabilities varied between the data types. The integrated community model also provided more accurate and more precise parameter estimates than alternative single-species and single-data-source models in many instances. We applied the model to a community of 11 herbivore species in the Masai Mara National Reserve, Kenya, and found considerable interspecific variation in response to local wildlife management practices: Five species showed higher abundances in a region with passive conservation enforcement (median across species: 4.5× higher), three species showed higher abundances in a region with active conservation enforcement (median: 3.9× higher), and the remaining three species showed no abundance differences between the two regions. Furthermore, the community average of abundance was slightly higher in the region with active conservation enforcement but not definitively so (posterior mean: higher by 0.20 animals; 95% credible interval: 1.43 fewer animals, 1.86 more animals). Our integrated community modeling framework has the potential to expand the scope of inference over space, time, and levels of biological organization, but practitioners should carefully evaluate whether model assumptions are met in their systems and whether data integration is valuable for their applications.

Using computational approaches to enhance the interpretation of missense variants in the PAX6 gene.

The PAX6 gene encodes a highly-conserved transcription factor involved in eye development. Heterozygous loss-of-function variants in PAX6 can cause a range of ophthalmic disorders including aniridia. A key molecular diagnostic challenge is that many PAX6 missense changes are presently classified as variants of uncertain significance. While computational tools can be used to assess the effect of genetic alterations, the accuracy of their predictions varies. Here, we evaluated and optimised the performance of computational prediction tools in relation to PAX6 missense variants. Through inspection of publicly available resources (including HGMD, ClinVar, LOVD and gnomAD), we identified 241 PAX6 missense variants that were used for model training and evaluation. The performance of ten commonly used computational tools was assessed and a threshold optimization approach was utilized to determine optimal cut-off values. Validation studies were subsequently undertaken using PAX6 variants from a local database. AlphaMissense, SIFT4G and REVEL emerged as the best-performing predictors; the optimized thresholds of these tools were 0.967, 0.025, and 0.772, respectively. Combining the prediction from these top-three tools resulted in lower performance compared to using AlphaMissense alone. Tailoring the use of computational tools by employing optimized thresholds specific to PAX6 can enhance algorithmic performance. Our findings have implications for PAX6 variant interpretation in clinical settings.

Acute cardiovascular and muscular response to rowing ergometer exercise in artificial gravity - a pilot trial.

Prolonged immobilization and spaceflight cause cardiovascular and musculoskeletal deconditioning. Combining artificial gravity through short-arm centrifugation with rowing exercise may serve as a countermeasure. We aimed to compare the tolerability, muscle force production, cardiovascular response, and power output of rowing on a short-arm centrifuge and under terrestrial gravity. Twelve rowing athletes (4 women, aged 27.2 ± 7.4 years, height 179 ± 0.1 cm, mass 73.7 ± 9.4 kg) participated in two rowing sessions, spaced at least six weeks apart. One session used a short-arm centrifuge with +0.5 Gz, while the other inclined the rowing ergometer by 26.6° to mimic centrifugal loading. Participants started self-paced rowing at 30 W, increasing by 15 W every three minutes until exhaustion. We measured rowing performance, heart rate, blood pressure, ground reaction forces, leg muscle activation, and blood lactate concentration. Rowing on the centrifuge was well-tolerated without adverse events. No significant differences in heart rate, blood pressure, or blood lactate concentration were observed between conditions. Inclined rowing under artificial gravity resulted in lower power output (-33%, p < 0.001) compared to natural gravity, but produced higher mean and peak ground reaction forces (p < 0.0001) and increased leg muscle activation. Muscle activation and ground reaction forces varied with rotational direction. Rowing in artificial gravity shows promise as a strategy against cardiovascular and muscular deconditioning during long-term spaceflight, but further investigation is required to understand its long-term effects.

Study methodology impacts density-dependent dispersal observations: a systematic review.

The relationship between animal dispersal and conspecific density has been explored in various study systems but results in terms of both the magnitude and the direction of density dependence are inconsistent. We conducted a thorough review of the literature (2000-2023) and found k = 97 empirical studies of birds, fishes, herpetofauna (amphibians and reptiles), invertebrates, or mammals that had tested for a correlation between conspecific density and animal dispersal. We extracted categorical variables for taxonomic group, sex, age, migratory behavior, study design, dispersal metric, density metric and variable type, as well as temporal and spatial scale, to test each of their correlation with the effect of density on dispersal (Pearson's r) using linear regressions and multilevel mixed-effect modelling. We found certain biases in the published literature, highlighting that the impact of conspecific density on dispersal is not as widespread as it is thought to be. We also found no predominant trend for density-dependent dispersal across taxonomic groups. Instead, results show that the scale and metrics of empirical observations significantly affected analytical results, and heterogeneity measures were high within taxonomic groups. Therefore, the direction and magnitude of the interaction between density and dispersal in empirical studies could partially be attributed to the data collection method involved. We suggest that the contradictory observations for density-dependent dispersal could be explained by dispersal-dependent density, where density is driven by movement instead, and urge researchers to either test this interaction when applicable or consider this perspective when reporting results.

Low-dose azithromycin prophylaxis in patients with atrial fibrillation and chronic obstructive pulmonary disease.

Low-dose azithromycin prophylaxis is associated with improved outcomes in people suffering frequent exacerbations of chronic obstructive pulmonary disease (COPD), but the use of macrolides in patients with cardiovascular disease has been debated. To investigate the risk of adverse events after COPD exacerbations in patients with atrial fibrillation (AF) treated with azithromycin prophylaxis. Retrospective cohort study within the TriNetX Platform, including AF patients with COPD exacerbations. Risks of primary and secondary outcomes were recorded up to 30 days post-COPD exacerbations and compared between azithromycin users and azithromycin non-users. The primary outcomes were the risks for a composite of (1) cardiovascular (all-cause death, heart failure, ventricular arrhythmias, ischemic stroke, myocardial infarction, and cardiac arrest), and (2) hemorrhagic events (intracranial hemorrhage (ICH), and gastro-intestinal bleeding). Cox-regression analyses compared outcomes between groups after propensity score matching (PSM). After PSM, azithromycin users (n = 2434, 71 ± 10 years, 49% females) were associated with a lower 30-day risk of post-exacerbation cardiovascular (HR 0.67, 95% CI 0.61-0.73) and hemorrhagic composite outcome (HR 0.45, 95% CI 0.32-0.64) compared to azithromycin non-users (n = 2434, 72 ± 11 years, 51% females). The beneficial effect was consistent for each secondary outcomes, except ICH. On sensitivity analyses, the reduced risk of adverse events in azithromycin users was irrespective of smoking status, exacerbation severity, and type of oral anticoagulation. Azithromycin prophylaxis is associated with a lower risk of all-cause death, thrombotic and hemorrhagic events in AF patients with COPD. The possible role of azithromycin prophylaxis as part of the integrated care management of AF patients with COPD needs further study.

Multiomic Signatures of Traffic-Related Air Pollution in London Reveal Potential Short-Term Perturbations in Gut Microbiome-Related Pathways.

This randomized crossover study investigated the metabolic and mRNA alterations associated with exposure to high and low traffic-related air pollution (TRAP) in 50 participants who were either healthy or were diagnosed with chronic pulmonary obstructive disease (COPD) or ischemic heart disease (IHD). For the first time, this study combined transcriptomics and serum metabolomics measured in the same participants over multiple time points (2 h before, and 2 and 24 h after exposure) and over two contrasted exposure regimes to identify potential multiomic modifications linked to TRAP exposure. With a multivariate normal model, we identified 78 metabolic features and 53 mRNA features associated with at least one TRAP exposure. Nitrogen dioxide (NO2) emerged as the dominant pollutant, with 67 unique associated metabolomic features. Pathway analysis and annotation of metabolic features consistently indicated perturbations in the tryptophan metabolism associated with NO2 exposure, particularly in the gut-microbiome-associated indole pathway. Conditional multiomics networks revealed complex and intricate mechanisms associated with TRAP exposure, with some effects persisting 24 h after exposure. Our findings indicate that exposure to TRAP can alter important physiological mechanisms even after a short-term exposure of a 2 h walk. We describe for the first time a potential link between NO2 exposure and perturbation of the microbiome-related pathways.

Quantitative Analogue Simulation of Planar Molecules.

Synthetic quantum systems provide a pathway for exploring the physics of complex quantum matter in a programmable fashion. This approach becomes particularly advantageous when it comes to systems that are thermodynamically unfavorable. By sculpting the potential landscape of Cu(111) surfaces with carbon monoxide quantum corrals in a cryogenic scanning tunneling microscope, we created analogue simulators of planar organic molecules, including antiaromatic and non-Kekulé species that are generally reactive or unstable. Spectroscopic imaging of such synthetic molecules reveals close replications of molecular orbitals obtained from ab initio calculations of the organic molecules. We further illustrate the quantitative nature of such analogue simulators by faithful extraction of bond orders and global aromaticity indices, which are otherwise technically daunting using real molecules. Our approach therefore sets the stage for new research frontiers pertaining to the quantum physics and chemistry of designer nanostructures.

Systematic review of the effectiveness of standalone passive countermeasures on microgravity-induced physiologic deconditioning.

A systematic review of literature was conducted to evaluate the effectiveness of passive countermeasures in ameliorating the cardiopulmonary and musculoskeletal effects of gravitational unloading on humans during spaceflight. This systematic review is the third of a series being conducted by the European Space Agency to evaluate the effectiveness of countermeasures to physiologic deconditioning during spaceflight. With future long-duration space missions on the horizon, it is critical to understand the effectiveness of existing countermeasures to promote astronaut health and improve the probability of future mission success. An updated search for studies examining passive countermeasures was conducted in 2021 to supplement results from a broader search conducted in 2017 for all countermeasures. Ground-based analogue and spaceflight studies were included in the search. A total of 647 articles were screened following removal of duplicates, of which 16 were included in this review. Data extraction and analysis, quality assessment of studies, and transferability of reviewed studies to actual spaceflight based on their bed-rest protocol were conducted using dedicated tools created by the Aerospace Medicine Systematic Review Group. Of the 180 examined outcomes across the reviewed studies, only 20 were shown to have a significant positive effect in favour of the intervention group. Lower body negative pressure was seen to significantly maintain orthostatic tolerance (OT) closer to baseline as comparted to control groups. It also was seen to have mixed efficacy with regards to maintaining resting heart rate close to pre-bed rest values. Whole body vibration significantly maintained many balance-related outcome measures close to pre-bed rest values as compared to control. Skin surface cooling and centrifugation both showed efficacy in maintaining OT. Centrifugation also was seen to have mixed efficacy with regards to maintaining VO2max close to pre-bed rest values. Overall, standalone passive countermeasures showed no significant effect in maintaining 159 unique outcome measures close to their pre-bed rest values as compared to control groups. Risk of bias was rated high or unclear in all studies due to poorly detailed methodologies, poor control of confounding variables, and other sources of bias (i.e. inequitable recruitment of participants leading to a higher male:female ratios). The bed-rest transferability (BR) score varied from 2-7, with a median score of 5. Generally, most studies had good BR transferability but underreported on factors such as control of sunlight or radiation exposure, diet, level of exercise and sleep-cycles. We conclude that: (1) Lack of standardisation of outcome measurement and methodologies has led to large heterogeneity amongst studies; (2) Scarcity of literature and high risk of bias amongst existing studies limits the statistical power of results; and (3) Passive countermeasures have little or no efficacy as standalone measures against cardiopulmonary and musculoskeletal deconditioning induced by spaceflight related to physiologic deterioration due to gravity un-loading.

Air quality on UK diesel and hybrid trains.

Concentrations of particulate matter (PM10, PM2.5), ultrafine (UFP), particle number (PNC), black carbon (BC), nitrogen dioxide (NO2) and nitrogen oxides (NOX) were measured in train carriages on diesel and bi-mode trains on inter-city and long-distance journeys in the United Kingdom (UK) using a high-quality mobile measurement system. Air quality on 15 different routes was measured using highly-time resolved data on a total of 119 journeys during three campaigns in winter 2020 and summer 2021; this included 13 different train classes. Each journey was sampled 4-10 times with approximatively 11,000 min of in-train concentrations in total. Mean-journey concentrations were 7.552 µg m-3 (PM10); 3.936 µg m-3 (PM2.5); 333-11,300 # cm-3 (PNC); 225-9,131 # cm-3 (UFP); 0.6-11 µg m-3 (BC); 28-201 µg m-3 (NO2); and 130-3,456 µg m-3 (NOX). The impact of different factors on in-train concentrations was evaluated. The presence of tunnels was the factor with the largest impact on the in-train particle concentrations with enhancements by a factor of 40 greater than baseline for BC, and a factor 6 to 7 for PM and PNC. The engine fuel mode was the factor with the largest impact on NO2 with enhancements of up to 14-times larger when the train run on diesel compared to the times running on electric on hybrid trains. Train classes with an age < 10 years observed the lowest in-train PM, BC and NOX concentrations reflecting improvements in aspects of rail technology in recent years. Air quality on UK diesel trains is higher than ambient concentrations but has lower PM2.5 and PNC than most other transport modes, including subway systems, diesel and petrol cars. This paper adds significantly to the evidence on exposure to poor air quality in transport micro-environments and provides the industry and regulatory bodies with reference-grade measurements on which to establish in-train air quality guidelines.

Macroalgal deep genomics illuminate multiple paths to aquatic, photosynthetic multicellularity.

Macroalgae are multicellular, aquatic autotrophs that play vital roles in global climate maintenance and have diverse applications in biotechnology and eco-engineering, which are directly linked to their multicellularity phenotypes. However, their genomic diversity and the evolutionary mechanisms underlying multicellularity in these organisms remain uncharacterized. In this study, we sequenced 110 macroalgal genomes from diverse climates and phyla, and identified key genomic features that distinguish them from their microalgal relatives. Genes for cell adhesion, extracellular matrix formation, cell polarity, transport, and cell differentiation distinguish macroalgae from microalgae across all three major phyla, constituting conserved and unique gene sets supporting multicellular processes. Adhesome genes show phylum- and climate-specific expansions that may facilitate niche adaptation. Collectively, our study reveals genetic determinants of convergent and divergent evolutionary trajectories that have shaped morphological diversity in macroalgae and provides genome-wide frameworks to understand photosynthetic multicellular evolution in aquatic environments.

Supporting equitable care of patients transferred from police watch-houses to the emergency department: A qualitative study of the perspectives of emergency doctors.

OBJECTIVE: People detained in short-term police custody often have complex health conditions that may necessitate emergency care, yet little is known about their management in EDs. The present study aimed to understand ED doctors' experiences and perceptions regarding the appropriateness and management of detainee transfers from police watch-houses to the EDs. METHODS: A qualitative descriptive study, using semi-structured interviews undertaken with ED doctors working in five purposively sampled EDs across Queensland, Australia. Data were analysed using inductive content analysis. RESULTS: Fifteen ED specialists and trainees participated. Participants reported that their overarching approach was to provide equitable care for watch-house detainees, as they would for any patient. This equitable approach needed to be responsive to complicating factors common to this population, including presence of police guards; restraints; complexity (physical/mental/social) of presentation; reliance on police to transport; ED doctors' often limited understanding of the watch-house environment; justice processes and uncertain legal disposition; communication with the watch-house; and detainees misreporting symptoms. Thresholds for assessment and treatment of detainees were contextualised to the needs of the patient, ED environment, and imperatives of other relevant agencies (e.g. police). Participants often relied on existing strategies to deliver quality care despite challenges, but also identified a need for additional strategies, including education for ED staff; improved communication with watch-houses; standardised paperwork; extended models of watch-house healthcare; and integrated medical records. CONCLUSIONS: Providing equitable healthcare to patients transported from watch-houses to the EDs is challenging but essential. Numerous opportunities exist to enhance the delivery of optimal care for this underserved population.

Inter-annual trends of ultrafine particles in urban Europe.

Ultrafine particles (UFP, those with diameters ≤ 100 nm), have been reported to potentially penetrate deeply into the respiratory system, translocate through the alveoli, and affect various organs, potentially correlating with increased mortality. The aim of this study is to assess long-term trends (5-11 years) in mostly urban UFP concentrations based on measurements of particle number size distributions (PNSD). Additionally, concentrations of other pollutants and meteorological variables were evaluated to support the interpretations. PNSD datasets from 12 urban background (UB), 5 traffic (TR), 3 suburban background (SUB) and 1 regional background (RB) sites in 15 European cities and 1 in the USA were evaluated. The non-parametric Theil-Sen's method was used to detect monotonic trends. Meta-analyses were carried out to assess the overall trends and those for different environments. The results showed significant decreases in NO, NO2, BC, CO, and particle concentrations in the Aitken (25-100 nm) and the Accumulation (100-800 nm) modes, suggesting a positive impact of the implementation of EURO 5/V and 6/VI vehicle standards on European air quality. The growing use of Diesel Particle Filters (DPFs) might also have clearly reduced exhaust emissions of BC, PM, and the Aitken and Accumulation mode particles. However, as reported by prior studies, there remains an issue of poor control of Nucleation mode particles (smaller than 25 nm), which are not fully reduced with current DPFs, without emission controls for semi-volatile organic compounds, and might have different origins than road traffic. Thus, contrasting trends for Nucleation mode particles were obtained across the cities studied. This mode also affected the UFP and total PNC trends because of the high proportion of Nucleation mode particles in both concentration ranges. It was also found that the urban temperature increasing trends might have also influenced those of PNC, Nucleation and Aitken modes.

Recommendations for reporting equivalent black carbon (eBC) mass concentrations based on long-term pan-European in-situ observations.

A reliable determination of equivalent black carbon (eBC) mass concentrations derived from filter absorption photometers (FAPs) measurements depends on the appropriate quantification of the mass absorption cross-section (MAC) for converting the absorption coefficient (babs) to eBC. This study investigates the spatial-temporal variability of the MAC obtained from simultaneous elemental carbon (EC) and babs measurements performed at 22 sites. We compared different methodologies for retrieving eBC integrating different options for calculating MAC including: locally derived, median value calculated from 22 sites, and site-specific rolling MAC. The eBC concentrations that underwent correction using these methods were identified as LeBC (local MAC), MeBC (median MAC), and ReBC (Rolling MAC) respectively. Pronounced differences (up to more than 50 %) were observed between eBC as directly provided by FAPs (NeBC; Nominal instrumental MAC) and ReBC due to the differences observed between the experimental and nominal MAC values. The median MAC was 7.8 ± 3.4 m2 g-1 from 12 aethalometers at 880 nm, and 10.6 ± 4.7 m2 g-1 from 10 MAAPs at 637 nm. The experimental MAC showed significant site and seasonal dependencies, with heterogeneous patterns between summer and winter in different regions. In addition, long-term trend analysis revealed statistically significant (s.s.) decreasing trends in EC. Interestingly, we showed that the corresponding corrected eBC trends are not independent of the way eBC is calculated due to the variability of MAC. NeBC and EC decreasing trends were consistent at sites with no significant trend in experimental MAC. Conversely, where MAC showed s.s. trend, the NeBC and EC trends were not consistent while ReBC concentration followed the same pattern as EC. These results underscore the importance of accounting for MAC variations when deriving eBC measurements from FAPs and emphasize the necessity of incorporating EC observations to constrain the uncertainty associated with eBC.

Occupational exposure to particulate matter and staff sickness absence on the London underground.

The London Underground (LU) employs over 19,000 staff, some of whom are exposed to elevated concentrations of particulate matter (PM) within the network. This study quantified the occupational exposure of LU staff to subway PM and investigated the possible association with sickness absence (SA). A job exposure matrix to quantify subway PM2.5 staff exposure was developed by undertaking measurement campaigns across the LU network. The association between exposure and SA was evaluated using zero-inflated mixed-effects negative binomial models. Staff PM2.5 exposure varied by job grade and tasks undertaken. Drivers had the highest exposure over a work shift (mean: 261 µg/m3), but concentrations varied significantly by LU line and time the train spent subway. Office staff work in office buildings separate to the LU network and are unexposed to occupational subway PM2.5. They were found to have lower rates of all-cause and respiratory infection SA compared to non-office staff, those who work across the LU network and are occupational exposed to subway PM2.5. Train drivers on five out of eight lines showed higher rates of all-cause SA, but no dose-response relationship was seen. Only drivers from one line showed higher rates of SAs from respiratory infections (incidence rate ratio: 1.24, 95% confidence interval 1.10-1.39). Lower-grade customer service (CS) staff showed higher rates of all-cause and respiratory infection SA compared to higher grade CS staff. Doctor-certified chronic respiratory and cardiovascular SAs were associated with occupational PM2.5 exposure in CS staff and drivers. While some groups with higher occupational exposure to subway PM reported higher rates of SA, no evidence suggests that subway PM is the main contributing factor to SA. This is the largest subway study on health effects of occupational PM2.5 exposure and may have wider implications for subway workers, contributing to safer working environments.

Arginine-Selective Bioconjugation Reagent for Effective 18F-labeling of Native Proteins.

Protein-based 18F-PET tracers offer new possibilities in early disease detection and personalized medicine. Their development relies heavily on the availability and effectiveness of 18F-prosthetic groups. We prepared and evaluated a novel arginine-selective prosthetic group, 4-[18F]fluorophenylglyoxal ([18F]FPG). [18F]FPG was radiosynthesized by a one-pot, two-step procedure with a non-decay-corrected (n.d.c.) isolated radiochemical yield (RCY) of 41 ± 8% (n = 10). [18F]FPG constitutes a generic tool for 18F-labeling of various proteins, including human serum albumin (HSA), ubiquitin, interleukin-2, and interleukin-4 in ∼30-60% n.d.c. isolated RCYs. [18F]FPG conjugation with arginine residues is highly selective, even in the presence of a large excess of lysine, cysteine, and histidine. [18F]FPG protein conjugates are able to preserve the binding affinity of the native proteins while also demonstrating excellent in vivo stability. The [18F]FPG-HSA conjugate has prolonged blood retention, which can be applied as a potential blood pool PET imaging agent. Thus, [18F]FPG is an arginine-selective bioconjugation reagent that can be effectively used for the development of 18F-labeled protein radiopharmaceuticals.

Variability of ambient air ammonia in urban Europe (Finland, France, Italy, Spain, and the UK).

This study addressed the scarcity of NH3 measurements in urban Europe and the diverse monitoring protocols, hindering direct data comparison. Sixty-nine datasets from Finland, France, Italy, Spain, and the UK across various site types, including industrial (IND, 8), traffic (TR, 12), urban (UB, 22), suburban (SUB, 12), and regional background (RB, 15), are analyzed to this study. Among these, 26 sites provided 5, or more, years of data for time series analysis. Despite varied protocols, necessitating future harmonization, the average NH3 concentration across sites reached 8.0 ± 8.9 µg/m3. Excluding farming/agricultural hotspots (FAHs), IND and TR sites had the highest concentrations (4.7 ± 3.2 and 4.5 ± 1.0 µg/m3), followed by UB, SUB, and RB sites (3.3 ± 1.5, 2.7 ± 1.3, and 1.0 ± 0.3 µg/m3, respectively) indicating that industrial, traffic, and other urban sources were primary contributors to NH3 outside FAH regions. When referring exclusively to the FAHs, concentrations ranged from 10.0 ± 2.3 to 15.6 ± 17.2 µg/m3, with the highest concentrations being reached in RB sites close to the farming and agricultural sources, and that, on average for FAHs there is a decreasing NH3 concentration gradient towards the city. Time trends showed that over half of the sites (18/26) observed statistically significant trends. Approximately 50 % of UB and TR sites showed a decreasing trend, while 30 % an increasing one. Meta-analysis revealed a small insignificant decreasing trend for non-FAH RB sites. In FAHs, there was a significant upward trend at a rate of 3.51[0.45,6.57]%/yr. Seasonal patterns of NH3 concentrations varied, with urban areas experiencing fluctuations influenced by surrounding emissions, particularly in FAHs. Diel variation showed differing patterns at urban monitoring sites, all with higher daytime concentrations, but with variations in peak times depending on major emission sources and meteorological patterns. These results offer valuable insights into the spatio-temporal patterns of gas-phase NH3 concentrations in urban Europe, contributing to future efforts in benchmarking NH3 pollution control in urban areas.