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Item type:Publication, Spatial distribution and isotopic signatures of N and C in mosses across Europe(Elsevier, 2025-01-01)Sheila Izquieta-Rojano, Yasser Morera-Gómez, David Elustondo, Esther Lasheras, Carolina Santamaría, Julen Torrens-Baile, Renate Alber, Lambe Barandovski, Mahmut Coşkun, Munevver Coskun, Helena Danielsson, Ludwig De Temmerman, Harry Harmens, Zvonka Jeran, Sébastien Leblond, Javier Martínez-Abaigar, Encarnación Núñez-Olivera, Roland Pesch, Juha Piispanen, Gerhard Soja, Zdravko Spiric, Trajče Stafilov, Lotti Thöni, Jesús Miguel SantamaríaThe accumulation of nitrogen (N) in moss tissue has proven to be a reliable marker of increasing N deposition. However, this measurement does not offer additional data about the origin of pollution. In this respect, the analysis of the N isotopic ratios might be a helpful tool in providing supplementary information about the nature of the nitrogenous species in biomonitoring surveys. Furthermore, isotopic signatures have been extensively used in the study of N and carbon (C) biogeochemical cycles. The main purpose of this study was to determine N and C elemental contents and their stable isotopes in mosses to investigate atmospheric pollution patterns across Europe. We aimed at identifying the main N polluted areas and evaluating the potential use of isotopic signatures in the attribution of pollution sources at a regional scale. With these objectives in mind, >1300 samples from 15 countries from Europe, all of them participants of the ICP-Vegetation programme 2005–2006, were analyzed for their C and N contents and δ15N and δ13C. The results were compared to those derived from EMEP model, which provided modeled deposition and emission data, as well as to the predominant land uses at the sampling sites (based on CORINE Land Cover). This evaluation suggests that additional measurements of stable C and N isotopes in mosses could be a valuable tool in European environmental surveys. Such measurements not only provide useful information for identifying probable pollution sources but also enable the quantification of their contributions, serving as biological indicators of significant environmental processes. This study presents the first quantitative assessment of major atmospheric nitrogen (N) sources based on stable isotope analysis on a European scale, establishing a framework for evaluating historical changes in N across the region. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Mercury Pollution in Terrestrial Ecosystems of North Macedonia: Insights from an 18-Year Moss Biomonitoring Programme(MDPI, 2025-12-22)Katerina Bačeva Andonovska, Robert Šajn, Jasminka Alijagić, Trajče Stafilov, Lambe BarandovskiMoss biomonitoring was conducted in 2002, 2005, 2010, 2015 and 2020 to evaluate atmospheric mercury (Hg) deposition across N. Macedonia as part of a comprehensive survey of potentially toxic elements (PTEs). More than 70 samples of the dominant moss species Hypnum cupressiforme and Homalothecium lutescens were collected during the summer field campaigns. Mercury concentrations were determined using cold vapour atomic absorption spectrometry and inductively coupled plasma mass spectrometry (ICP-MS). The results revealed marked temporal fluctuations: median Hg content increased from 56 µg/kg in 2002 to 68 µg/kg in 2005, peaked at 93 µg/kg in 2010, then decreased to 84 µg/kg in 2015, and further to 52 µg/kg in 2020. Over the study period, Hg concentrations ranged from 10 to 595 µg/kg, with the highest variability observed in 2010. Spatial distribution maps and regional comparisons indicate that elevated Hg contents correspond predominantly to anthropogenic sources, particularly in industrialised zones and regions affected by mining and metallurgical activities. The 2020 dataset shows a significantly lower median value (52 µg/kg) compared to previous surveys, indicating a slight improvement in air quality, although local hotspots persist. These results highlight the importance of long-term moss biomonitoring as a cost-effective approach for tracking atmospheric mercury trends and informing national environmental policy. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Докторска дисертација: ОПРЕДЕЛУВАЊЕ ДИЈАГНОСТИЧКИ РЕФЕРЕНТНИ ВРЕДНОСТИ КАЈ МАМОГРАФСКИТЕ СНИМАЊА(PMF-UKIM, 2025-12-04)Mirjeta Mediji Arifi (Мирјета Медији Арифи)Diagnostic reference levels (DRLs) in digital mammography were determined from 31 040 digital mammography images acquired from diagnostic and screening examination data from eight state-managed mammography centers/units in the Republic of North Macedonia (RM). The main objective is to establish a diagnostic reference level for mammography examinations at different ranges of breast thickness. Approximately 30 000 mammography images were used to evaluate mean glandular dose (MGD) and compressed breast thickness (CBT) for each projection, craniocaudal (CC) and mediolateral oblique (MLO). The stratified DRL was derived by calculating the 75th percentile of the MGD across all the samples at various CBT ranges for both projections. The overall median MGDs, minimum, and maximum were calculated to be 1.15 mGy, 0.1 mGy, and 9.93 mGy, respectively. As the CBT increased from 7 to 120 mm, the 75th percentile of the MGD increased from 0.94 mGy to 3.67 mGy for CC, and from 0.44 mGy to 4.91 mGy for MLO projections. The study established local DRLs for the digital mammography systems at the 75th percentile, which compared well with the values reported for other countries/regions. The DRL defined per CC and MLO image view for a specific CBT indicated that at least one mammography facility needs optimization. In mammography, radiation dose is typically expressed as the Mean Glandular Dose (MGD), which represents the dose delivered to the glandular tissue of the breast. This study compares MGD estimates obtained using three different methodologies: (I) MGD-Dance-LIBRA – Calculated manually for each patient using Dance’s formula, incorporating Mammographic Breast Density (MBD) values derived from the LIBRA application (Laboratory for Individualised Breast Radiodensity Assessment), thereby replacing Dance’s standard glandularity assumption with image-specific values; (II) MGD-Dance – Calculated using Dance’s formula with the conventional assumption of 50% glandularity; (III) MGD-Displayed – Extracted directly from the DICOM header of each mammogram. A total of 688 anonymized mammograms from 172 women undergoing routine screening were analyzed, with complete technical and patient-related data. The mean MGD values obtained by the three methods were: MGD-Dance-LIBRA: 2.97 mGy; MGD-Dance: 2.78 mGy; MGD-Displayed: 2.81 mGy. The average glandularity across the dataset was estimated at 14%. A strong correlation was observed between MGD-Dance and MGD-Dance-LIBRA values (R² = 0.9865). The refined dose estimation using image-specific glandularity from LIBRA consistently produced slightly higher values compared to the standard Dance method, highlighting the impact of the commonly assumed 50% glandularity, which overestimates the true average density. Incorporating individualized breast density estimates from the LIBRA application into Dance’s formula provides a more refined and accurate method for calculating Mean Glandular Dose in digital mammography In a systematic review, we examine the establishment of Diagnostic Reference Levels (DRLs) in digital mammography across 18 European countries, based on studies from 2005 to 2025. A total of 353 articles were identified through the comprehensive search of academic networks: Google Scholar, PubMed, Research Gate, and Academia. Only 18 peer-reviewed studies met the inclusion criteria reporting Mean Glandular Dose (MGD)-based DRLs from Finland to Malta. Eight studies used patient data, four used phantom measurements, and six used both. To overcome the challenging comparison of the variety of reported parameters, we undertook some data harmonisation procedures, focusing on a common Compressed Breast Thickness (CBT) range of 50–59 mm. The DRLs varied notably by country, with 75th percentile MGDs ranging from 1.1 to 2.6 mGy and 95th percentile from 1.6 to 2.9 mGy, averaging to 1.44 mGy, which is lower than the achievable European level (2 mGy). The harmonisation approach enabled the derivation of a comparable dataset of average MGDs, facilitating cross-country comparisons and insights into radiation dose optimisation in digital mammography across Europe.