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Combining residue analysis of floors and ceramics for the study of activity areas at the Garum Shop at Pompeii
No full textLocal habitat and seascape structure influence seagrass fish assemblages in the Venice lagoon: the value of conservation at multiple spatial scales.
No full textSeagrass meadows are a critical component of estuarine and coastal seascapes, and their structure influences fish assemblages at multiple spatial scales. The patch mosaic mode l, which defines the seascape as a collection of interacting habitat types, is increasingly dopted to prioritise protected areas and design ecological restoration schemes, hence helping to preserve seagrass meadows and the associated fish assemblages. Despite that, the re are few studies investigating the relative contribution of environmental characteristics measured at different spatial scales in determining the distribution of seagrass fish. This study collects fish and environmental observations taken at both site and seascape scales in seagrass meadows in the Venice lagoon (Adriatic Sea, Italy). By means of generalised linear models, it aims to disentangle the relative influence of local water qua
lity and habitat characteristics from that of habitat mosaic properties, investigating the response of whole fish assemblage descriptors, feeding guilds and dominant species. While confirming the primary importance of local habitat quality
, the study highlights that also seagrass habitat structure at the seascape scale is relevant for seagrass fish assemblages, influencing total biomass, biomass of macrobenthivorous and hyperbenthivorous/piscivorous species and seagrass specialists
such as syngnathids. Conservation of seagrass fish assemblages can therefore be promoted in Mediterranean coastal lagoons by preserving or restoring some features of the habitat mosaic, namely the extension of seagrass patches and their shape complexity, in addition to local water quality and seagrass cover
Iron(III) N,N-Dialkylcarbamate-Catalyzed Formation of Cyclic Carbonates from CO2 and Epoxides under Ambient Conditions by Dynamic CO2 Trapping as Carbamato Ligands
No full textCarbon-dots from sugars and ascorbic acid: Role of the precursors on morphology, properties, toxicity and drug uptake
No full textThere is the need for reproducible, simple, high-yielding synthetic protocols aimed at obtaining Carbon Dots (CDs) with controlled surface properties, fluorescence, photothermal and photochemical behavior, biocompatibility, tumor targeting ability, drug absorption biodistribution and tumor uptake. This paper describes a systematic study on the effect of glucose, fructose and ascorbic acid as starting materials for the preparation of highly luminescent CDs, characterized by a blue emission. Their composition and morphology are investigated by titration of OH surface groups, spectroscopic techniques, high-resolution-transmission electron microscopy (HR-TEM) and their toxicity was tested toward HeLa cells. CDs made using fructose were toxic while CDs made from glucose and ascorbic acid showed good biocompatibility. The reproducible and simple synthetic procedure yields luminescent biomass-derived CDs for combined cancer therapy and diagnostics. Their doxorubicin (DOX) drug loading capabilities were measured by spectrofluorimetry indicating a crucial role of the morphologies of the CDs in controlling DOX uptake. The glucose derived CDs showed up to 28 %w/w of DOX loading
La morte degli animali d'affezione nel mondo romano: per una "zooepigrafia" tra ritualità e sentimento
No full textSigma-hole bonds: a new tool for high-performance liquid chromatography enantioseparations
No full textNon-covalent interactions play a key role in many areas of science such as crystal engineering, molecular recognition and biology. Recently, various types of the so-called s-hole bonds have been identified and studied as a new family of non-covalent interactions. A sigma-hole bond (sB) is a non-covalent interaction (RD ···A) between a covalently-bonded atom of Groups IV-VII (D, donor), bearing a region with a positive electrostatic potential on unpopulated sigma* orbitals, and a negative site (A, acceptor). Among these interactions, halogen- and chalcogen-bonds involve atoms of groups VI and VII as donor sites,respectively, and, in the last years, the interest in their fundamentals and applications has been grown rapidly. Moreover, in the last decade, sigmaBs occurring in solution have received attention as a tool to direct molecular recognition processes and underlie protein-ligand binding. However some issues are still open: i) so far, the investigations on sBs have mainly been focused on their description in vacuum and in solid state, whereas the behaviour in solution has received less attention; ii) another open issue concerns the application of sigmaBs in chiral systems, and only few chiral molecules having s-holes as recognition sites were described recently ; iii) in particular, the detection of weak stereoselective s-hole-based interactions in solution requires the availability of analytical method
characterized by high sensitivity; iv) currently, only four halogen bond-driven enantiodiscrimination processes are known. Recently, we reported the first series of halogen bond-driven enantioseparations observed in High-
Performance Liquid Chromatography (HPLC) environment]. This result is related to the ability of heavy halogens (iodine and bromine) as halogen bond donor (chiral analyte) to form linear interactions with
carbonyl oxygen atoms as halogen bond acceptor (polysaccharide-based support as chiral stationary phase). On this basis, we describe herein the fundamentals of an innovative approach to detect and study
weak stereoselective sigmaBs in solution, which is based on: i) the rational design of atropisomeric sigmaB donors based on the 4,4’-bipyridyl core, ii) the application of a HPLC protocol based on an orthogonal on-column screening on polysaccharide-based polymers, and iii) DFT calculations and computational simulations to study the involved mechanisms. Significantly, the enantioseparations of fluorinated 3-(arylthio)-4,4’-bipyridines proved that S•••O
chalcogen bonds can drive enantiodiscrimination processes in HPLC environment. As a result of the HPLC study, new structures can be successfully pinpointed for further applications in catalysis, molecular recognition and drug design
