Incidence and Predictors of Infections and All-Cause Death in Patients with Cardiac Implantable Electronic Devices: The Italian Nationwide RI-AIAC Registry

The incidence of infections associated with cardiac implantable electronic devices (CIEDs) and patient outcomes are not fully known. To provide a contemporary assessment of the risk of CIEDs infection and associated clinical outcomes. In Italy, 18 centres enrolled all consecutive patients undergoing a CIED procedure and entered a 12-months follow-up. CIED infections, as well as a composite clinical event of infection or all-cause death were recorded. A total of 2675 patients (64.3% male, age 78 (70-84)) were enrolled. During follow up 28 (1.1%) CIED infections and 132 (5%) deaths, with 152 (5.7%) composite clinical events were observed. At a multivariate analysis, the type of procedure (revision/upgrading/reimplantation) (OR: 4.08, 95% CI: 1.38-12.08) and diabetes (OR: 2.22, 95% CI: 1.02-4.84) were found as main clinical factors associated to CIED infection. Both the PADIT score and the RI-AIAC Infection score were significantly associated with CIED infections, with the RI-AIAC infection score showing the strongest association (OR: 2.38, 95% CI: 1.60-3.55 for each point), with a c-index = 0.64 (0.52-0.75), p = 0.015. Regarding the occurrence of composite clinical events, the Kolek score, the Shariff score and the RI-AIAC Event score all predicted the outcome, with an AUC for the RI-AIAC Event score equal to 0.67 (0.63-0.71) p < 0.001. In this Italian nationwide cohort of patients, while the incidence of CIED infections was substantially low, the rate of the composite clinical outcome of infection or all-cause death was quite high and associated with several clinical factors depicting a more impaired clinical status

Wintertime vertical distribution of air pollution in suburban Fairbanks during the ALPACA 2022 field campaign

International audienceThe Alaskan Layered Pollution and Chemical Analysis (ALPACA) field campaign investigated the sources and processing of wintertime urban pollution in Fairbanks, Alaska in January and February 2022. Several sites located around the city of Fairbanks collected data to study the underexplored cold and dark wintertime dynamical, physical and chemical processes driving air pollution, both outdoors and indoors. We deployed a tethered balloon system at a farm field site near the University of Alaska (UAF) to specifically investigate the vertical layering of pollution and influence of different emission altitudes on surface pollution levels.The study site is located in a suburban area, west of downtown Fairbanks. Observational efforts there focused mainly on surface exchanges and the vertical distribution of pollutants in relation to the boundary layer structure, specifically under stable (inversion) conditions. Instruments at the UAF-farm provided continuous ground measurements of aerosol physical, optical and chemical properties, trace gases (O3, CO, N2O) and meteorology. The newly designed Modular Multiplatform Air Compatible Measurement System (MoMuCAMS) was deployed with a tethered-balloon (helikite) to sample air up to 350 m above ground level, providing information on the vertical distribution and mixing processes of atmospheric pollutants. Instruments onboard MoMuCAMS provided information on aerosol characteristics (particle number concentration, size distribution, absorption coefficient and chemical composition), trace gases (CO2, O3, CO, N2O, NOx), and meteorology. MoMuCAMS performed 21 flights between January 26 and February 25, 2021, collecting roughly 140 individual profiles of varying altitude under different boundary layer conditions, intercepting pollution plumes at different heights and of different composition. Given the suburban location of the study site, we measured the influence of polluted air from the city and “cleaner” air from more remote origins.We will show how the vertical structure of the atmosphere and the frequently occurring temperature inversions affect transport and dispersion of pollution at different heights and how different meteorological conditions affect local air circulation and pollution at the study site

Analysis of the vertical dispersion of pollution layers in the urban Arctic during the ALPACA 2022 field campaign

International audienceThe Alaskan Layered Pollution and Chemical Analysis (ALPACA) field campaign was conducted during the winter months of January and February 2022 to examine urban pollution sources and transformations in Fairbanks, Alaska. Several data collection sites were set up throughout the city to investigate the less-explored dynamic, physical, and chemical mechanisms governing air pollution events during the cold and dark winter.The vertical dispersion of pollutants was investigated from an observation site in the suburban area just outside downtown Fairbanks. It featured ground-based measurements, a ten-meter mast for eddy covariance measurements, and a tethered balloon for vertical profiling of the atmosphere. Sampling included measurements of aerosol microphysical characteristics and trace gases (CO, CO2, O3, NOx). Meteorological parameters were also continuously measured at 2m and 10m from the mast, and also during the balloon flights. The tethered balloon was deployed to assess the vertical mixing of pollutants under stable atmospheric conditions from sources located at the surface but also at higher elevations, such as emissions from high power plant stacks.A total of 148 individual profiles (up to a maximum altitude of 350 m above ground level) from 24 flights were collected between January 26 and February 25, 2022. The atmospheric conditions featured surface-based temperature inversions (SBI) in 86% of the cases due to the upwelling longwave radiation dominating the surface energy budget. Interestingly, eight flights captured elevated pollution plumes from power plants located downtown. The analysis of profiles reveals that the atmospheric stability and mixing of the surface layer was affected by two mechanisms. On one hand, radiative cooling promoted strong SBI locally, suppressing turbulence. On the other hand, a drainage flow at the surface from a nearby valley increased the shear stress at the surface, promoting mechanical turbulence near the surface. The measurements show how these two competing mechanisms affect the mixing of the surface layer.The second part of the study focuses on the vertical dispersion of elevated plumes. The vertical mixing of pollutant plumes and their potential to contribute to surface pollution are investigated using the chemical and physical signature of the plumes and their vertical extents.Together, the results of this study contribute to improving our understanding of pollution mixing under the very stable conditions typical of the Arctic winter and can help to design pollution mitigation strategies by identifying the conditions and mechanisms leading to high pollution events

Characterization of size-segregated particles turbulent fluxes in an Arctic city (Fairbanks, Alaska)

International audienceWintertime air pollution affects air quality of Arctic and sub-Arctic urban areas, because of the coupling between strong local emissions for residential heating and energy production and poor atmospheric dispersion associated with a stratified planetary boundary layer. Aerosols represent priority pollutants in such environments, and their behaviour in the Arctic wintertime boundary layer not only impacts air quality but also determines deposition on snow or ice surfaces, leading to chemical and physical modifications in the snowpack. The interactions between boundary layer meteorology and air pollution were the focus of the international ALPACA (Alaskan Layered Pollution and Chemical Analysis) field campaign held in January and February 2022 in Fairbanks (AK, USA). The aim of the present work is to analyse the fluxes of atmospheric particles in at a urban background site in Fairbanks, based on continuous observations of aerosol concentration, size distributions, and size-segregated deposition velocities. The EC system was installed at the suburban site of UAF (University of Alaska Farm), located nearby the foothills bordering the city basin. The main micrometeorological parameters and fluxes (wind field, friction velocity, turbulent kinetic energy, and sensible heat flux) were characterized in terms of boundary layer conditions (occurrence of thermal inversions, dynamic stratifications, vertical wind shear, slope currents, coherent turbulence structures). The aerosol eddy covariance system was based on a condensation particle counter (CPC) - able to measure particles down to 5 nm in diameter - and an Optical Particle Counter Optical Particle Counter (OPC) for evaluating particle fluxes in the accumulation mode (0.25 < dp < 0.8 μm) and quasi-coarse mode (0.8 < dp < 3 μm). The median number concentration was 13 E+3 cm−3, 76 cm−3 and 0.3 cm−3 for ultrafine, accumulation and quasi-coarse particles mode, with higher concentrations found at low wind speeds. The particle fluxes showed a net emission pattern for the ultrafine, accumulation and quasi-coarse dimensional mode, especially in daytime, with average values of 203, 0.3, and 0.02 cm-2 s-1 respectively. Deposition periods were observed most frequently for air masses from the city located to the east, while local emission sources due to traffic lead emission fluxes, especially in the accumulation mode. We discuss the particle flux measurements in the context of parallel aerosol and gaseous pollutants determined by fixed and mobile platforms (a tethered balloon and a car) as well as of determinations of depositions in the snow pack across the Fairbanks area

Vertical profiles of pollutants in Fairbanks, Alaska during the ALPACA 2022 field campaign

International audienceThe ALPACA (Alaskan Layered Pollution and Chemical Analysis) field campaign (January-February 2022) aimed to collect new data to document Arctic wintertime air pollution. State of the art instrumentation was deployed in Fairbanks, Alaska to characterise inorganic/organic aerosols, vertical layering and mixing of aerosols and precursors, and meteorology at sites influenced by local anthropogenic emissions and background Arctic Haze.Vertical profiles of the boundary layer composition were collected from an instrumented tethered ballon (helikite) deployed at the UAF-Farm site in West Fairbanks. The Helikite payload included instruments dedicated to the characterisation of particles (concentration, composition, size distribution) and to measurement of trace gases with dedicated analysers for O3, CO and CO2 and a MICROMEGAS instrument. MICROMEGAS is a light-weight package based on low-cost Alphasense electrochemical sensors for trace gases (CO/O3/NO/NO2). This instrument was also deployed on the ground close to reference-grade trace gas analysers at the CTC measurement site in downtown Fairbanks, and onboard a vehicle for 2D-mapping of pollution within and around Fairbanks.Low-cost electrochemical sensors are sensitive to temperature and humidity and require careful calibration and validation. We first introduce the calibration method based on multi-linear regression with the collocated CTC reference measurements. The performance (biases, correlation coefficients, RMSDs) of the calibrated data are then evaluated against CTC observations not used for the calibration. Cases of vertical helikite profiles with polluted layers related to specific dynamical conditions (temperature inversions, wind regimes…) are investigated. Tracer-tracer relationships (CO, NO, NO2 versus CO2 ; NOx versus Ox) together with meteorological observations are used to examine air mass origins (domestic combustion, vehicles, power plants), as well as dilution and chemical transformation of the sampled pollution plumes

Investigating the relative contributions of power plant and surface emissions to air pollution in Fairbanks, Alaska during the wintertime ALPACA 2022 campaign

International audienceLocal air pollution sources in the Arctic lead to poor air quality in Arctic cities, particularly during the winter months. Fairbanks in central Alaska, is a prime example of such an Arctic city which suffers from acute wintertime pollution episodes. The topography of Fairbanks (situated in a basin), coupled with strong surface-based temperature inversions, contributes to stable meteorological conditions that hinder the dispersion of pollutants and surface temperatures reaching -40 °C. These harsh winter conditions result in enhanced domestic and power plant combustion emissions. Stable meteorological regimes are frequently interspersed with less stable episodes, resulting in vertical mixing between surface and elevated inversion layers. However, there are many uncertainties in our understanding about pollution sources and secondary aerosol formation under cold, dark winter conditions, where photochemistry is limited. These issues were addressed through the collection of comprehensive datasets on atmospheric composition and meteorology in Fairbanks, during the international ALPACA (Alaskan Layered Pollution and Chemical Analysis) field campaign in January and February 2022. Data were collected at the surface and vertical profiles were collected using a tethered balloon (EPFL Helikite).Here, we examine the relative contributions and distributions of power plant emissions, emitted above the surface, and surface emission sources to pollution levels in the Fairbanks region. The FLEXPART-Weather Research and Forecasting (WRF) Lagrangian particle dispersion model, driven by meteorological fields from WRF-Environmental Protection Agency (EPA, Alaska) simulations is deployed. Firstly, model runs are used to evaluate the transport and dispersion of emissions from power plants at several altitudes in and around Fairbanks. Surface-based and elevated temperature inversions, characteristic of the winter boundary layer in Fairbanks, are considered in a parameterisation of power plant plume injection heights, and temporal variations in these emissions is also taken into account. Secondly, the extent to which power plant emissions are contributing to surface pollution is investigated using power plant (point source) and sector-based surface EPA emissions at 1.3km resolution at hourly time resolution during the 2022 campaign period. Model results are evaluated against available vertical profile and ground-based observations from ALPACA 2022. Power plant plumes are simulated aloft at several ALPACA measurement sites, as validated by vertical profile observations. The simulations indicate that power plant emissions are mixed down towards the surface in some cases. These results also provide insights into relative source contributions from each power plant in Fairbanks within the vertical profile of the lower atmospheric boundary layer, which could be used as tool for source apportionment studies

Investigating processes affecting wintertime air pollution variability and estimating contributions of power plant emissions relative to the surface in the stratified Arctic boundary layer

International audienceThe Arctic is warming rapidly compared to the global average. As Arctic warming continues, urbanisation and industrial activities are predicted to increase, along with complex climate and ecosystem feedbacks. Therefore, local sources of air pollutants are expected to play an increasingly significant role in Arctic environmental changes in the coming years. Poor air quality is already a growing public health issue in Arctic and sub-Arctic cities. During wintertime, stable meteorological conditions and the persistence of strong surface-based temperature inversions suppress the dispersion of pollutants, which accumulate due to enhanced emissions linked to high energy demands. Fairbanks, in central Alaska, is an example of a sub-Arctic city that suffers from acute wintertime pollution episodes. The city’s topography (situated in a basin), strong stratification of the Arctic boundary layer (ABL), and high emissions, primarily from domestic heating at the surface, and power plant stacks aloft, are known to contribute to the problem. However, interactions between vertical stratification of the ABL and dispersal of pollutants from surface and elevated sources are poorly quantified due to a lack of observations and complexities of the ABL structure and dynamics. To address these uncertainties, comprehensive atmospheric composition and meteorological measurements were collected at the surface, and vertical profiles were obtained using a tethered balloon during the international ALPACA (Alaskan Layered Pollution and Chemical Analysis) field campaign in January and February 2022.Here, we explore the contribution of power plants and surface emission sources to pollution concentrations in the Fairbanks region. We use the FLEXPART-Weather Research and Forecasting (WRF) Lagrangian particle dispersion model, driven by meteorological fields from US Environmental Protection Agency (EPA) WRF simulations including data assimilation of meteorological observations, to simulate the evolution of selected emission tracers. Hourly power plant and sector-based surface EPA emissions at 1.3km resolution during ALPACA 2022 are included in the model runs. A novel model parameterisation of power plant plume injection heights accounts for the ABL structure, notably surface-based and elevated temperature inversions. Model results are evaluated against available observations from ALPACA 2022, and sensitivity to, for example, emissions and vertical mixing is explored. The simulation of pollution plume altitudes is significantly improved when ABL stratification is taken into account in the plume rise parameterisation since inversion layers can trap plumes. Variability in modelled surface pollutant concentrations is predominantly driven by meteorology, and the ability of the model to capture surface-based temperature inversions (as low as 10m). A cold-temperature dependence for NOx vehicle emissions, currently missing from the EPA emission inventory, is required to reproduce the magnitude of observed NOx surface concentrations at low temperatures below 0°C and needs to be considered in future emission inventories in the Arctic, and potentially in other wintertime environments. Finally, using the most realistic simulation, we estimate the contribution of power plant emissions to surface pollution in the Fairbanks region, addressing an important policy question. The results indicate preferential areas for downward transport of pollution from aloft and larger contributions to surface pollution under less stable meteorological conditions

Prognostic Factors of Non-Predominant-Lepidic Lung Adenocarcinoma Presenting as Ground Glass Opacity: Results of a Multicenter Study

This study aims to define the clinicopathological characteristics and prognosis of non-predominant lepidic invasive adenocarcinoma presenting as Ground Glass Opacity (GGO) nodules. The goal is to assess statistical relationships between histology, tumor size, location, and the incidence of relapse and lymph node dissemination. A retrospective multicenter study was conducted, including patients with GGO observed on CT scans between 2003 and 2021. Anamnestic, radiological, and histological data, as well as SUV values, lymphatic and vascular invasion, pathological stage, resection type, and adjuvant treatment, were analyzed. The primary endpoints were to evaluate prognostic factors for death and recurrence using Cox regression analysis. All 388 patients, including 277 with non-predominant lepidic invasive adenocarcinoma and 161 with lepidic adenocarcinoma, underwent curative anatomical resection. Non-predominant lepidic invasive adenocarcinoma demonstrated a worse prognosis than lepidic adenocarcinoma (p = 0.001). Independent prognostic factors for death and recurrence included lymph node involvement (p = 0.002) and vascular and lymphatic invasion (p < 0.001). In conclusion, non-predominant lepidic invasive adenocarcinoma and lymphatic and vascular invasion are prognostic factors for death and recurrence in GGO patients. Results suggest adjuvant treatment in the case of pN1-N2 disease, emphasizing the necessity of lymphadenectomy (sampling or systematic) for accurate staging and subsequent therapeutic procedures

Identifying sources of local air pollution in Fairbanks, Alaska using FLEXPART-WRF simulations and observational data from the ALPACA 2022 campaign

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