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4. Automated Quality Control Solution for Radiographic Imaging of Lung Diseases.

Author

Kleefeld, Christoph, Castillo Lopez, Jorge Patricio, Costa, Paulo R., Fitton, Isabelle, Mohamed, Ahmed, Pesznyak, Csilla, Ruggeri, Ricardo, Tsalafoutas, Ioannis, Tsougos, Ioannis, Wong, Jeannie Hsiu Ding, Zdesar, Urban, Ciraj-Bjelac, Olivera, and Tsapaki, Virginia

Subjects
*IMAGE quality in radiography, *QUALITY control, *X-ray imaging, *PULMONOLOGY, *IMAGING systems
Abstract

Background/Objectives: Radiography is an essential and low-cost diagnostic method in pulmonary medicine that is used for the early detection and monitoring of lung diseases. An adequate and consistent image quality (IQ) is crucial to ensure accurate diagnosis and effective patient management. This pilot study evaluates the feasibility and effectiveness of the International Atomic Energy Agency (IAEA)'s remote and automated quality control (QC) methodology, which has been tested in multiple imaging centers. Methods: The data, collected between April and December 2022, included 47 longitudinal data sets from 22 digital radiographic units. Participants submitted metadata on the radiography setup, exposure parameters, and imaging modes. The database comprised 968 exposures, each representing multiple image quality parameters and metadata of image acquisition parameters. Python scripts were developed to collate, analyze, and visualize image quality data. Results: The pilot survey identified several critical issues affecting the future implementation of the IAEA method, as follows: (1) difficulty in accessing raw images due to manufacturer restrictions, (2) variability in IQ parameters even among identical X-ray systems and image acquisitions, (3) inconsistencies in phantom construction affecting IQ values, (4) vendor-dependent DICOM tag reporting, and (5) large variability in SNR values compared to other IQ metrics, making SNR less reliable for image quality assessment. Conclusions: Cross-comparisons among radiography systems must be taken with cautious because of the dependence on phantom construction and acquisition mode variations. Awareness of these factors will generate reliable and standardized quality control programs, which are crucial for accurate and fair evaluations, especially in high-frequency chest imaging. [ABSTRACT FROM AUTHOR]

Published
2024
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45. Sulfur-containing species (sulfate and methanesulfonate) in coastal Antarctic aerosol and precipitation

Author

Minikin, Andreas, Legrand, Michel, Hall, Julie, Wagenbach, Dietmar, Kleefeld, Christoph, Wolff, Eric, Pasteur, Elizabeth Claire, Ducroz, François, Minikin, Andreas, Legrand, Michel, Hall, Julie, Wagenbach, Dietmar, Kleefeld, Christoph, Wolff, Eric, Pasteur, Elizabeth Claire, and Ducroz, François

Abstract

The concentrations of sulfur-containing species (sulfate and methanesulfonate (MSA)) of aerosols collected at three coastal Antarctic sites (Neumayer, Dumont d'Urville, and Halley) have been studied in order to investigate the natural sulfur cycle at high southern latitudes. The multiple-year data sets indicate annual mean concentrations of MSA and non-sea-salt (nss) sulfate of 38 and 151 ng m−3 at Neumayer (1983–1995) and 20 and 147 ng m−3 at Dumont d'Urville (1991–1995). On the basis of the study of a more limited time period (1991 and 1992), the Halley data set indicates significantly lower MSA and nss sulfate concentrations, 15 and 50 ng m−3, respectiveley. The concentrations of both species exhibit a consistent and strong seasonal cycle with maxima from December to March and minima from May to September (from 2 to 4 and from 17 to 50 ng m−3, for MSA and nss sulfate, respectively). These data, together with radionuclide studies (210Pb and 10Be), indicate that the marine biogenic source dominates the sulfur budget of the boundary layer of these regions throughout the year. The contribution of other sources, such as the long-range transported sulfur from continents and to a lesser extent the stratospheric sulfate reservoir, remains weak when averaged over the year. Differences in the seasonal pattern of the two sulfur-containing species, as well as intersite differences in the summer concentrations, are compared to several factors, mainly the spatial and temporal variations of the chlorophyll content of the surface ocean water and the seasonality of the sea ice cover. This permits investigation of the respective influence of marine regions emitting dimethylsulfide located either near the Antarctic continent (south of 60°S) or at more temperate latitudes. A strong correlation is found between the chlorophyll content of the Antarctic ocean and the level of total nss sulfur. Furthermore, nss sulfate and MSA deposition fluxes determined from firn and ice cores extract

Published
1998

46. Coastal new particle formation: Environmental conditions and aerosol physicochemical characteristics during nucleation bursts

Author

O'Dowd, Colin D., primary, Hämeri, Kaarle, additional, Mäkelä, Jyrki, additional, Väkeva, Minna, additional, Aalto, Pasi, additional, de Leeuw, Gerrit, additional, Kunz, Gerard J., additional, Becker, Edo, additional, Hansson, Hans‐Christen, additional, Allen, Andrew G., additional, Harrison, Roy M., additional, Berresheim, Harald, additional, Kleefeld, Christoph, additional, Geever, Michael, additional, Jennings, S. Gerard, additional, and Kulmala, Markku, additional

Published
2002
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48. Transport of boreal forest fire emissions from Canada to Europe

Author

Forster, Caroline, primary, Wandinger, Ulla, additional, Wotawa, Gerhard, additional, James, Paul, additional, Mattis, Ina, additional, Althausen, Dietrich, additional, Simmonds, Peter, additional, O'Doherty, S., additional, Jennings, S. Gerard, additional, Kleefeld, Christoph, additional, Schneider, Johannes, additional, Trickl, Thomas, additional, Kreipl, Stephan, additional, Jäger, Horst, additional, and Stohl, Andreas, additional

Published
2001
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