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Lichens as biomonitors of depleted uranium in Kosovo
No full textThis paper reports the results of a study using lichens as biomonitors to investigate the environmental distribution of depleted uranium (DU) at selected Kosovo sites as a consequence of the use of DU ordnance during the conflict of 1999. The results suggested that the use of DU ammunitions did not cause a diffuse environmental contamination in such a way to have caused a detectable U enrichment in lichens. Also isotopic U-235/U-238 measurements did not indicate the presence of DU particles in lichens, except for some samples at a heavily shelled site, which resulted contaminated by DU
Bioaccumulo , fisiologia e proteomica del lichene evernia prunastri (L.) ach. esposto a differenti intensità di traffico veicolare
No full textNell’area urbana e peri-urbana della città di Siena gli input di contaminazione atmosferica possono essere ricondotti, ad eccezione del riscaldamento domestico nel periodo invernale, esclusivamente al traffico veicolare in quanto, la presenza di altre fonti di emissione, come le attività industriali e artigianali sono rispettivamente subordinate e minoritarie. Lo studio degli effetti di tale inquinamento sui licheni risulta tuttavia di difficile comprensione dati sia la molteplicità dei contaminanti in gioco sia i possibili effetti di
sinergismo e antagonismo a cui i talli risultano esposti.
In questo studio nell’ambiente urbano di Siena sono state individuate tre zone aventi differenti caratteristiche di traffico veicolare: area urbana (zona all’interno delle mura cittadine), area perimetrale (perimetro dell’area urbana
retrostante la cinta muraria cittadina), area peri-urbana. È stata altresì selezionata una stazione di controllo all’interno dell’orto botanico della città ubicata a ridosso dell’area urbana. All’interno di ciascuna area e nella stazione di controllo sono stati eseguiti, con cadenza stagionale, dei trapianti di talli di Evernia prunastri per la durata complessiva di un anno. Dopo ogni periodo di esposizione sono state misurate le concentrazioni degli elementi in traccia (Al, As, Ba, Cd, Cr, Cr, Cu, Fe, Mn, Ni, Pb, Pd, Pt, Sb, Zn) e sono stati valutati alcuni parametri fisiologici (contenuto di pigmenti fotosintetici, efficienza fotosintetica, contenuto di ergosterolo, danneggiamento delle membrane cellulari). I risultati evidenziano che le concentrazioni degli elementi in traccia e i parametri fisiologici sono in stretta
relazione con le diverse condizioni di traffico veicolare e con la stagionalità. Questi dati sono stati integrati con un’analisi di proteomica che ha fornito risultati interessanti anche se non di facile interpretazione
Lichens as biomonitors of uranium and other trace elements in an area of Kosovo heavily shelled with depleted uranium rounds
No full textThis paper reports the results of a study using lichens as biomonitors to investigate the small-scale environmental distribution of uranium and other trace elements in an area of Kosovo (Djakovica) heavily shelled with depleted uranium (DU) anti-tank ammunition. The results of total uranium concentrations showed great variability and species-specific differences, mainly due to differences in the exposed surface area of the lichens. The uranium concentrations in lichen samples were rather similar at a site heavily shelled with DU ammunition and at a control site. Unexpectedly, the highest uranium concentrations were found at the control site. The observed U distribution can be explained by contamination of lichen thalli by soil particles. The soil geochemistry was similar at the two sampling sites. The 235U/ 238U ratios in the soil samples suggested a modest DU contribution only at the heavily shelled site. Measurements of U isotopes in lichens did not reveal DU pollution at the control site. The U isotopic ratios in lichens at the shelled site showed variable figures; only two samples were clearly contaminated by DU. There were no signs of contamination by other trace elements. © 2003 Elsevier Ltd. All rights reserved
The high contents of lead in soils of northern Kosovo
No full textA soil-based geochemical survey was carried out in an area of about 350 km2 in northern Kosovo around the Zvečan Pb-Zn smelter. The concentrations of As, Cd, Co, Cr, Cu, Ni, Pb, Sb, Tl, Th, U, Zn were determined in 452 topsoil and 82 subsoil samples. High contents of Pb, Cd, As, Sb, Zn and Cu were found in topsoil over a vast area including the Ibar and Sitnica river valleys. The highest concentrations were usually measured close to the Zvečan smelter. In some zones, the lead contents in surface soils exceeded 5000 mg/kg. Arsenic and antimony levels were usually more than 200 and 50 mg/kg, respectively, while cadmium contents were in the range 5-20 mg/kg. South of the Zvečan area, lead, antimony and cadmium pollution was strong in the densely populated urban area of Kosovska Mitrovica and along the agricultural alluvial plain of the Sitnica River. Depending on the chemical element, the pollution extended 15-22 km north and south of the Zvečan smelter. There was a progressive decrease of heavy element concentrations with increasing distance from the smelting plant. The contents of Pb, Zn, Cu, As, Cd, Sb significantly decreased with soil depth; in fact, the pollution only affected the upper 50 cm of soil. Crops were affected by soil pollution and many food-stuffs exceeded the EU standards. Suggestions for soil remediation are given
Nature-based solutions for monitoring the impact of vehicular particulate matter and for the preventive conservation of the Palatine Hill archaeological site in Rome, Italy
Get PDFMagnetic and chemical biomonitoring methodologies were applied to the southern slopes of the Palatine Hill archaeological area in Rome, Italy. Plant leaves and lichen transplants were respectively sampled and exposed between July 2022 and June 2023 to assess the impact of vehicular particulate matter from Via dei Cerchi, a trafficked road coasting Circus Maximus, towards the archaeological area upon the Palatine Hill. The magnetic properties of leaves and lichens, inferred from magnetic susceptibility, hysteresis loops and first order reversal curves, were combined with the concentration of trace elements. It was demonstrated that the bioaccumulation of magnetite-like particles, associated with tracers of vehicular emissions, such as Ba and Sb, decreased with longitudinal distance from the road, without any important influence of elevation from the ground. Lichens demonstrated to be more efficient biomonitors of airborne PM than leaves, irrespective of the plant species. Conversely, leaves intercepted and accumulated all PM fractions, including road dusts and resuspended soil particles. Thus, plant leaves are suitable for providing preventive conservation services that limit the impact of particulate pollution on cultural heritage sites within busy metropolitan contexts
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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