Search results for " Marine"
showing 10 items of 1338 documents
Simulation d'images d'un futur imageur multispectral géostationaire dédié à la couleur de l'eau : étude de l'influence des angles d'observation et d'…
2011
Improvements of optical sensors now make it possible to launch medium spatial and high spectral resolution sensors on the Geostationary Earth Orbit (GEO). The GEO allows sensors to observe the Earth with high temporal resolution, unlike Low Earth Orbit (LEO) satellites. The objective of this thesis is to simulate radiance images that would be provided by a theoretical ocean color sensor, on a geostationary orbit, in order to characterize the images to be acquired, to specify the future instruments and to validate the image processing algorithms. For this purpose, we have combined a radiative transfer model for ocean waters (Hydrolight) and a radiative transfer model for the atmosphere (MODT…
Using natural analogues to investigate the effects of climate change and ocean acidification on Northern ecosystems
2018
AbstractNorthern oceans are in a state of rapid transition. Still, our knowledge of the likely effects of climate change and ocean acidification on key species in the food web, functionally important habitats and the structure of Arctic and sub-Arctic ecosystems is limited and based mainly on short-term laboratory studies on single species. This review discusses how tropical and temperate natural analogues of carbonate chemistry drivers, such as CO2 vents, have been used to further our knowledge of the sensitivity of biological systems to predicted climate change, and thus assess the capacity of different species to show long-term acclimation and adaptation to elevated levels of pCO2. Natur…
Il delicato equilibrio tra la tutela dell'ambiente e la promozione delle attività economiche nella pianificazione dello spazio marino
2023
L’ambiente marino è costantemente esposto a molteplici pressioni per effetto delle attività umane in mare e a terra, dunque, è senza dubbio uno degli esempi più evidenti della complessità insita nella ricerca di un equilibrio tra le istanze della tutela dell’ambiente e quelle della pianificazione territoriale. La tutela dell’ambiente marino, infatti, richiede una gestione accurata dello spazio marittimo e costiero per garantire che l’utilizzo delle risorse disponibili sia compatibile con la preservazione degli ecosistemi e con le esigenze delle future generazioni. La strategia normativa posta in essere dal legislatore negli ultimi decenni non è riuscita, tuttavia, a migliorare concretamente…
New 1,2,4-oxadiazole nortopsentin derivatives with cytotoxic activity
2019
New analogs of nortopsentin, a natural 2,4-bis(3&prime
New Bioactive Peptides from the Mediterranean Seagrass Posidonia oceanica (L.) Delile and Their Impact on Antimicrobial Activity and Apoptosis of Hum…
2023
The demand for new molecules to counter bacterial resistance to antibiotics and tumor cell resistance is increasingly pressing. The Mediterranean seagrass Posidonia oceanica is considered a promising source of new bioactive molecules. Polypeptide-enriched fractions of rhizomes and green leaves of the seagrass were tested against Gram-positive (e.g., Staphylococcus aureus, Enterococcus faecalis) and Gram-negative bacteria (e.g., Pseudomonas aeruginosa, Escherichia coli), as well as towards the yeast Candida albicans. The aforementioned extracts showed indicative MIC values, ranging from 1.61 μg/mL to 7.5 μg/mL, against the selected pathogens. Peptide fractions were further analyzed thr…
Synthesis and Antitumor Activity of New Thiazole Nortopsentin Analogs
2016
New thiazole nortopsentin analogs in which one of the two indole units was replaced by a naphthyl and/or 7-azaindolyl portion, were conveniently synthesized. Among these, three derivatives showed good antiproliferative activity, in particular against MCF7 cell line, with GI50 values in the micromolar range. Their cytotoxic effect on MCF7 cells was further investigated in order to elucidate their mode of action. Results showed that the three compounds act as pro-apoptotic agents inducing a clear shift of viable cells towards early apoptosis, while not exerting necrotic effects. They also caused cell cycle perturbation with significant decrease in the percentage of cells in the G0/G1 and S ph…
The fate of terrestrial and riverine materials in a Mediterranean seagrass bed
2009
Ecology and extent of freshwater browning - What we know and what should be studied next in the context of global change
2022
Water browning or brownification refers to increasing water color, often related to increasing dissolved organic matter (DOM) and carbon (DOC) content in freshwaters. Browning has been recognized as a significant physicochemical phenomenon altering boreal lakes, but our understanding of its ecological consequences in different freshwater habitats and regions is limited. Here, we review the consequences of browning on different freshwater habitats, food webs and aquatic-terrestrial habitat coupling. We examine global trends of browning and DOM/DOC, and the use of remote sensing as a tool to investigate browning from local to global scales. Studies have focused on lakes and rivers while seldo…
Aree marine e parchi archeologici sommersi
2008
Major ions and trace elements composition of rainwater around the two industrial areas of Milazzo and Priolo Gargallo (Sicily - Italy)
2023
This database shows the concentration of major ions and trace elements in rainwater from two polluted industrial areas of Sicily, Milazzo and Priolo Gargallo, collected from June 2018 to July 2019, through a network of 11 bulk collectors to sample bulk atmospheric deposition, for a total of 131 samples collected. Different sources, both natural and anthropogenic, for both major ions and trace elements have been recognised. This study also highlighted some critical issues with common methods of sampling and analysing atmospheric deposition. The analysis and comparison of two different aliquots, filtered and unfiltered rainwater, has shown that the filtration method removes from the sample a …