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ENGLISH VERSION Introduction- The impact of the anthropic activities in polar and remote regions is an in-depth scrutinized issue, however, little is known about the role of the emerging contaminants in such environments. In this context, long-lasting and stable Fragrances, widely used in household and personal care products, due to their volatility are emerging contaminants recently recognized to be atmospherically transported over long distances (Vecchiato et al., 2018, 2020), but their environmental fate is still largely unknown. Activities- Fragrances, namely Amyl Salicylate, Oranger Crystals, Hexyl Salicylate, Ambrofix, Peonile and Benzyl Salicylate, were found in the coastal seawater of the Ross Sea, Antarctica (Vecchiato et al., 2017) and in seawater and snow samples of the Svalbard Islands (Vecchiato et al., 2018). Local emissions from both the Arctic and Antarctic research bases were revealed, together with the evidence of Long-Range Atmospheric Transport (LRAT) of these substances. Moreover, an ice core retrieved on Elbrus, Caucasus, showed a 20-fold increase of the deposition fluxes of fragrances (Vecchiato et al., 2020), accounting for the deep changes in their usage from 1950s onwards. In each of the investigated environments the allergenic and oestrogenic Salicylates resulted in general the most abundant and widespread components, reflecting their large global consumption. On-going and planned sampling campaigns both in the Arctic and Antarctica are focusing on the distribution of fragrances on inland and coastal snow, to identify the sources, the cold-condensation drivers and finally their environmental fate. Future developments- The ecotoxicological effects of these substances are very little known, but preliminary studies showed developmental toxicity for copepods at levels close to the environmental concentrations (10-100 ng L-1) (Picone et al., 2021), indicating a possible threat for marine ecosystems. Therefore, it is fundamental for future studies in polar environments to investigate the local sources, as well as the fluxes during the seasonal snowmelt, considering possible amplification phenomena. On the other hand, a better understanding of the atmospheric processes is needed, to increase the knowledge on the transport patterns and dynamics. ITALIAN VERSION introduzione- L'impatto delle attività antropiche negli ambienti polari e remoti è un argomento ampiamente dibattuto, tuttavia il ruolo dei contaminanti emergenti in queste aree è ancora poco compreso. In tale contesto, il trasporto a lungo raggio di composti volatili ma stabili, quali Fragranze ampiamente utilizzate in prodotti per la cura personale e della casa, è stato recentemente riconosciuto in aree remote (Vecchiato et al., 2018, 2020), benché la conoscenza del loro destino ambientale sia ancora limitata. Attività correnti- La presenza di una serie di fragranze, ovvero Amil Salicilato, Oranger Crystals, Esil Salicilato, Ambrofix, Peonile e Benzil Salicilato, è stata riscontrata in aree costiere del mare di Ross in Antartide (Vecchiato et al., 2017) e in campioni di acqua di mare e neve delle isole Svalbard (Vecchiato et al., 2018). Sono state identificate emissioni locali dalle basi di ricerca, sia artiche che antartiche, tuttavia accompagnate anche dall'evidenza del trasporto atmosferico a lungo raggio (LRAT) di queste sostanze. Inoltre, l'analisi di una carota di ghiaccio dal monte Elbrus, Caucaso, ha mostrato un incremento di venti volte dei flussi di deposizione delle fragranze (Vecchiato et al., 2020), descrivendo quindi i profondi cambiamenti nel loro utilizzo intercorsi dagli anni '50. In ciascuno di questi studi i composti salicilati, sostanze allergeniche ed estrogeniche, sono risultati generalmente i componenti più diffusi e abbondanti, riflettendo il loro ampio utilizzo a livello globale. Le campagne di campionamento in corso o pianificate negli ambienti polari si stanno focalizzando sulla distribuzione delle fragranze nella neve di aree sia costiere che interne, allo scopo di identificare le sorgenti, i processi di deposizione e infine il loro destino ambientale. Sviluppi futuri- Gli effetti ecotossicologici di queste sostanze sono poco conosciuti, ma studi preliminari hanno mostrato una tossicità nello sviluppo larvale dei copepodi a livelli paragonabili alle concentrazioni riscontrate in ambiente (10-100 ng L-1) (Picone et al., 2021), indicando possibili rischi per l'ecosistema marino. È pertanto fondamentale che i futuri studi negli ambienti polari possano considerare le sorgenti locali, ma anche il deflusso durante lo scioglimento stagionale della neve, anche considerando possibili fenomeni di amplificazione. È altrettanto necessario migliorare la conoscenza dei processi atmosferici coinvolti per poterne comprendere i meccanismi e le dinamiche di trasporto. REFERENCE/BIBLIOGRAFIA Picone, M., Distefano, G. G., Marchetto, D., Russo, M., Vecchiato, M., Gambaro, A., Barbante, C. and Ghirardini, A. V.: Fragrance materials (FMs) affect the larval development of the copepod Acartia tonsa: An emerging issue for marine ecosystems, 27 Ecotoxicol. Environ. Saf., 215, doi:10.1016/j.ecoenv.2021.112146, 2021. Vecchiato, M., Gregoris, E., Barbaro, E., Barbante, C., Piazza, R. and Gambaro, A.: Fragrances in the seawater of Terra Nova Bay, Antarctica, Sci. Total Environ., 593-594, 375-379, doi:10.1016/j.scitotenv.2017.03.197, 2017. Vecchiato, M., Barbaro, E., Spolaor, A., Burgay, F., Barbante, C., Piazza, R. and Gambaro, A.: Fragrances and PAHs in snow and seawater of Ny-Ålesund (Svalbard): Local and long-range contamination, Environ. Pollut., 242, 1740-1747, doi:10.1016/j.envpol.2018.07.095, 2018. Vecchiato, M., Gambaro, A., Kehrwald, N. M., Ginot, P., Kutuzov, S., Mikhalenko, V. and Barbante, C.: The Great Acceleration of fragrances and PAHs archived in an ice core from Elbrus, Caucasus, Sci. Rep., 10(1), 1-10, doi:10.1038/s41598-020-67642-x, 2020.

We investigated the elemental composition and water-soluble-organic compounds (WSOC) present in size-segregated airborne particulate matter (PM) in order to better understand: 1) the distribution of the water-soluble fraction of trace elements (TE), rare earth elements (REE) and WSOCs among different particulate sizes, and 2) the transport processes of aerosol towards the Arctic zone. Samples were collected at Ny-Alesund in the Svalbard Islands (78° 55' 07" N, 11° 53' 30"E) from 19 April to 14 September 2010. Water-soluble TE and REE were measured with the aim of recognising reliable tracers of specific sources, which may prove crucial in cost-effective strategies of air pollution control. The TE and REE content, especially in the finest fractions of aerosols in remote areas, is primarily due to long-range transport. It gives valuable information on the global circulation and on the contribution of human activities to aerosol composition (Birmili et al. 2006; Fernández-Espinosa et al. 2004; Song et al. 2001). On the same samples, we also determined water-soluble organic tracers as specific source indicators: levoglucosan and methoxyphenols from biomass burning, acrylamide from anthropogenic origin and amino acids from primary production. These results were discussed in previous papers (Scalabrin et al. 2012; Zangrando et al. 2013).

We present in this study comprehensive data on the occurrence of 25 trace and ultra-trace elements in the deepest part of the Vostok ice core. The determination of Li, Na, Mg, Al, K, Ca, V, Cr, Mn, Fe, Co, Cu, Zn, As, Se, Rb, Sr, Mo, Ag, Cd, Sb, Ba, Pb, Bi and U has been performed in the different types of ice encountered from 3271 m to 3609 m of depth, corresponding to atmospheric ice, glacial flour and to accreted ice originating from the freezing of Lake Vostok waters. From atmospheric ice and glacial flour, the relative contributions of primary aerosols were evaluated for each element using a chemical mass balance approach in order to provide a first order evaluation of their partition between soluble (sea-salt) and insoluble (wind-blown dust) fractions in the ice. Sea-salt spray aerosols are the main source of impurities to the ice for certain elements (Na, Mg and K levels, and in a lesser extent to Ca, Sr, Rb, Li and U) while for other elements (Al, V, Cr, Mn, Fe, Co, Cu, Zn, Mo, Sb, Ba and Pb as well as the non sea salt fractions of Mg, K, Ca, Sr, Rb, Li and U) dust inputs appear to primarily control their depositional variability. For the glacial flour, the comparable levels of elements with the overlying atmospheric ice suggest that incorporation of abrasion debris at the glacier is quite limited in the sections considered. For the accreted ice originating from the subglacial waters of Lake Vostok, we observed a major chemical shift in the composition of the ice showing two distinct trends that we assumed to be derived from the chemical speciation of elements. The study of the glacier ice and the glacial flour has allowed us to perform a detailed characterisation of elemental abundances related to the aerosol sources variability and also to illustrate the interaction between the ice-sheet and the bedrock.

AIM: To suggest a new classification system for sinonasal papilloma based on a critical analysis of surgical indications and results obtained. METHODS: We analysed surgical data from 84 cases of sinonasal papilloma treated endoscopically. RESULTS: In 58 males and 26 females, between 25 and 85 years, the ethmoid sinus (63 cases), the maxillary sinus (43), and the nasal fossa (22) were mostly involved. No case of endocranial extension or carcinoma was reported. Complications were reported in 15.4% of patients, as well as 5 recurrences (5.9%). Median follow up was 39,5 months. To categorise the tumour for the most appropriate surgical treatment, we propose a classification based on 6 main categories that depend on the location, origin and extension of the tumour. CONCLUSION: The classification that we propose presents advantages for prognosis and surgical indication in comparison with other classifications.

The aim of the POSEIDON project is to quantify the relative contribution of maritime traffic and harbor activities to atmospheric pollutants concentration in four port-cities of the Adriatic Sea. This study focuses on the harbors of Venice and Rijeka. In order to investigate the main pollution sources, emission inventories were used as input for receptor models: PMF (positive matrix factorization) and PCA (principal components analysis) ; moreover source identification was also conducted using PAHs diagnostic ratios. The ship traffic impact was quantified: i) on gaseous and particulate PAHs, collected using a new method which consisted in a double simultaneous sampling, in different wind sectors ; ii) applying PMF to data of metals, PAHs and ions in PM10 ; iii) using the vanadium concentration according to the Agrawal methodology.

Antarctica is almost entirely covered by an huge ice-sheet. In limited coastal areas, during only a short summer period, small and shallow seasonal lakes are fed by melted ice and snow. These have no or limited outlets and lose summer meltwater through evaporation or sublimation, accumulating solutes and particulate material from the catchment areas. The study of the effects of ice melting linked to the seasonal evolution of Antarctic lakes constitutes an experimental challenge. The waters of four lakes in Northern Victoria Land (Edmonson Point 14 and 15A, Inexpressible Island 10B and Tarn Flat 20) were sampled at the beginning and at the late/complete melting of ice, with the aim to highlight the seasonal evolution and amplification phenomena [1,2]. Both persistent organic pollutants (POPs, i.e. PCBs and PBDEs) and primary production indicators, such as L- and D- amino acids were determined in water samples. Combining the information deriving from the two classes of tracers allowed to obtain a more detailed indication of sources and processes. Samplings were carried out during the 2011-2012 austral summer. Pre-analytical steps were performed in the laboratories in Antarctica with particular attention to avoid contamination risks. PCBs and PBDEs were later analyzed by HRGC coupled to HRMS and LRMS (MAT95XP, Thermo Finnigan; 7890A-5975C, Agilent Technologies). The quantification of amino acids was performed using an HPLC with a chiral column coupled with an API 4000 triple quadrupole (AbSciex), achieving very low detection limits (4 - 200 ng L-1). PCBs showed a general slight increase during the melting season, while the behaviour of PBDEs resulted more complex, reflecting the influence of similar sources. The study of amino acids highlighted the role of local fauna, in particular in lake Edmonson Point 14, since the inputs of nutrients from seabirds greatly promoted the primary growth. Also the presence of bacteria was confirmed by relevant concentrations of D-alanine. An increase was observed also in lake 10B, probably due to marine inputs or evaporation linked to strong katabatic winds, while dilution phenomena were prevalent during the melting in the other lakes. Funds were provided by PNRA 2013/AZ2.05.

In this Section, we summarize the most important findings and relevant issues treated in detail in Chapters 2 to 5. The primary conclusion of this thesis is that it is necessary to take aerosols into account to accurately describe the convective atmospheric boundary-layer (CBL) dynamics and the land-surface processes. We reached this conclusion by systematically studying the land-CBL system and its couplings, and employed a hierarchy of models ranging from an eddy-resolving model (large-eddy simulation; LES) to non-eddy resolving models (mixed-layer model, and single column model). In addition to the numerical component, we used a complete observational data set to help us design and evaluate our numerical framework. Chapter 2 was devoted to the explanation of the radiative transfer code used in Chapters 4 and 5. We showed that despite the simplified treatment of solar radiation and its interactions with aerosols, our radiative code is in general agreement with a more sophisticated radiative transfer code, even for extreme aerosol loads. Moreover, our results reproduce observations of direct and diffuse radiation at the surface accordingly - as shown in Chapter 4. Regarding the longwave band, we showed that aerosols are not relevant for the estimation of the incoming longwave radiation at the surface. We concluded that Brunt's formula, depending only on screen level temperature and vapor pressure, is the most adequate to represent the incoming longwave radiation at the surface for the cases relevant for our studies. In Chapter 3 we investigated the impact of aerosol heat absorption on the dynamics of an idealized CBL with prescribed surface fluxes. We found that the structure and evolution of the CBL were influenced by the vertical distribution of the aerosols. Moreover, we showed that the aerosols influence the exchange of heat between the CBL and the free troposphere by (i) extinction of radiation and consequently reduced surface fluxes, and by (ii) deepening the entrainment zone depth. We highlighted the importance of high-resolution models to properly represent the effects of aerosol absorption of radiation on the dynamics of the CBL, especially in the entrainment zone. We demonstrated that, in addition to the properties of the aerosols, the vertical distribution is an important characteristic to properly describe the CBL height evolution and the dynamics of the upper part of the CBL. To further support the analysis of the LES results, we used a mixed-layer (MXL) model to calculate boundary-layer depth and the potential temperature jump at the inversion layer. In spite of the simplicity of this model, the mixed-layer results obtained for boundary-layer height and the inversion layer jump agreed well with the LES results. Extending the knowledge acquired with the academical prototypical experiments performed in Chapter 3, in Chapter 4 we quantified the effects of aerosol scattering and absorption of shortwave (SW) radiation both on the surface energy budget and on the CBL dynamics. To this end, we coupled our LES model and the MXL model to (i) a land-surface model and (ii) a broadband SW radiative transfer model, (described in Chapter 2). We successfully validated the results obtained with the LES model and MXL model using measurements of (thermo)dynamic variables and aerosol properties observed in Cabauw (the Netherlands). Our LES results showed that for Cabauw (over well-watered grassland) aerosols significantly alter the magnitude of the available energy at the surface and its partitioning. Under well-watered conditions, the sensible heat flux was more strongly reduced compared to the latent heat flux. Given the satisfactory agreement between the LES results and MXL model results, we further explored the sensitivity of the land-CBL system to a wide range of aerosol optical depths and single scattering albedos using the MXL model. Our results showed that higher loads of aerosols impose an energy restriction at the surface. As a result, we calculated a delay in the morning onset of the CBL and an advance in the CBL afternoon collapse. We also found that entrainment of aerosols from the residual layer plays a significant role in the development of the CBL dynamics during the day. An important aspect of Chapter 4 is the investigation of the different responses of the CBL dynamics depending on aerosol optical properties. Strongly absorbing aerosols deepened and warmed the CBL, while purely scattering aerosols shallowed and cooled the CBL. We highlighted that the results presented in Chapter 4 can be used as a benchmark to evaluate coupling and performance of the parametrizations for SW radiation, land-surface and boundary-layer schemes, implemented in mesoscale or global chemistry transport models. In Chapter 5 we increased the complexity of our land-CBL system representation by studying the formation and transport of ammonium nitrate aerosols. In doing so, we coupled in our LES radiation, chemistry, aerosols, CBL dynamics, and surface exchange processes of chemicals, heat and moisture. Our fully coupled LES model was again evaluated against observations of chemistry and aerosol fields and showed a good correspondence. In particular, our results showed a satisfactory agreement between the simulated and observed nitrate partitioning at the surface. We showed that gas-aerosol conversion of nitrate leads to highly non-linear profiles of nitrate concentrations and turbulent fluxes. Moreover, the shapes of the simulated profiles depended strongly on the time scale of gas-aerosol conversions. Note that the typical timescale of turbulent motions in the CBL is around 10-20 minutes. For shorter time scales of gas-aerosol conversion compared to the CBL dynamics timescale, we found that turbulent fluxes are larger and concentration profiles more tilted within the CBL. These results have a significant impact on the nitrate deposition flux at the surface. Our LES results confirmed that the large deposition velocities for aerosol nitrate close to the surface are actually due to outgassing of aerosol nitrate rather than a real deposition process. An important aspect discussed in Chapter 5 concerns the inability of non-eddy resolving models to accurately model the turbulent transport of nitrate within the CBL. Based on a detailed analysis of the flux budget equation, we showed that the exchange coefficient of heat used in our 1D model has to be increased to better account for the complex interaction between gas-aerosol conversion of nitrate and 3D turbulence within the CBL. Indeed, the new exchange coefficient also improved the comparison between gas-aerosol partitioning of nitrate calculated with our 1D model and surface observations. The results discussed in this thesis demonstrate the need for considering the influence of aerosols on the CBL dynamics. Specifically, aerosols influence important phenomena for the CBL evolution namely radiation, surface-atmosphere interactions, chemistry, and (thermo)dynamics. In addition to that, the availability of high-resolution numerical simulations is crucial to validate and evaluate results obtained by numerical models that do not explicitly resolve the turbulent field.

Tree Genetics & Genomes, 5 (1), ISSN:1614-2950, ISSN:1614-2942