41 research outputs found
L'abate Luigi Antonio Lanzi tra filologia classica e letteratura religiosa
No full textIntento del convegno è stato recuperare aspetti della vita e dell’opera di Luigi Lanzi (1732-1810) ad oggi poco noti, se non del tutto trascurati, dalla critica, eppure niente affatto superflui o secondari nell’offrire ulteriori spunti di comprensione e valutazione dello studioso e dell’opera sua tutta, compresa quella di antiquaria e di storia dell’arte, meglio discussa finora. Si è ritenuto opportuno ripartire pertanto dalla formazione di Lanzi, contestualizzata e puntualizzata in quell’itinerario spirituale e scientifico che da Fermo giunge al Collegio Romano (manca tuttora una vera e propria biografia del personaggio, salvo quelle ottocentesche - di prima mano, ma datate - di Onofrio e di Mauro Boni e di Fortunato Benigni). Al pari, è stata proposta, per la prima volta, l’analisi dei suoi scritti –editi o solo preparati per la pubblicazione – a carattere devozionale e filologico-letterario, in specie di ambito classico. Sono intervenuti: Angelo Bianchi (Università Cattolica di Milano), Robert Danieluk (Archivum Romanum Societatis Iesu), Flavio Rurale (Università di Udine), Fernando J. de Lasala (Pontificia Università Gregoriana, Roma), Fabrizio Capanni (Pontificia Commissione per i Beni Culturali della Chiesa), Gianni Festa (Facoltà Teologica dell’Emilia Romagna, Bologna), Giulia Pedace (Università di Roma ‘La Sapienza’), Francesca Martina Falchi (Università di Urbino), Paolo Fedeli (Università di Bari), Sotera Fornaro (Università di Sassari), Marco Buonocore (Biblioteca Apostolica Vaticana); hanno presieduto i lavori: Giovanna Perini, Renato Raffaelli, Guido Arbizzoni Artusi, Anna Santucci (Università di Urbino)
TOXICITY EVALUATION OF PLASTIC NANOPARTICLES ON AQUATIC ORGANISMS
No full textPlastics are an immense family of unique and versatile materials which play an essential role in modern society and are an indispensable part of our daily lives. With a global production of nearly 440 million tons in 2019, plastic waste has been described to accumulate in virtually any environment, from marine to freshwater ecosystems. The irreversibility and global ubiquity of marine plastic pollution has turned plastics into a potential planetary boundary threat. Nanoplastics (NPs) represent the smallest fraction of plastic litter and can result in the environment as the degradation products or larger plastic items. Nevertheless, only recently such particles have been detected in real environments, albeit not yet accurately quantified. Although today there is still a lack of clarity as regards their toxicological effects, the high exposure potential, together with the physical and chemical heterogeneity of NPs, the likely significant diffusive release of plastic additives and adsorbed substances, combined with their small size and enhanced accessibility to biological tissues, potentially make NPs highly hazardous pollutants. Ecological risk assessment of nanoplastics are urgently needed. In the absence of reliable environmental exposure estimates to date, ecotoxicological research has focused on defining a hazard assessment of NPs. This thesis aimed at investigating the mechanism of toxicity of NPs, taking advantage of high-throughput sequencing technologies. In an initial experiment, described in Chapter 2, adult specimens of the freshwater benthic crayfish Procambarus clarkii were exposed to 100 μg of 100 nm carboxylated polystyrene nanoparticles in a 72h dietary exposure experiment. The cosmopolitan red swamp crayfish Procambarus clarkii, is widely used as bioindicator of environmental pollution and was selected here as a representative non-model decapod of the freshwater ecosystem. An integrated approach was conceived to assess the biological effects of polystyrene NPs, by analyzing both transcriptomic and physiological responses. Total hemocyte counts, basal and total phenoloxidase activities, glycemia and total protein concentration were investigated in crayfish hemolymph at 0h, 24h, 48h and 72h to evaluate general stress response over time. Transcriptomes of hemocytes and hepatopancreas were analyzed after 72h. At the physiological level, crayfish were able to compensate for the induced stress by not exceeding the generic stress thresholds. The RNA-Sequencing analysis revealed the altered expression of few genes involved in immune response, oxidative stress, gene transcription and translation, protein degradation, lipid metabolism, oxygen demand, and reproduction in P. clarkii exposed to NPs. Activation of oxidative stress pathways and inflammatory responses has been widely recognized as primary molecular mechanisms of NPs-induced toxicity, in agreement with our findings. In particular, we note an alteration of several genes related to the ubiquitin-proteasome system, one of the major degradation pathways for maintaining cellular protein homeostasis, which has not been described before. Moreover, a rather clear transcriptomic response to NPs emerged as a strong downregulation of vitellogenin expression in the hepatopancreas of female crayfish, which may indicate a shift in energy allocation induced by plastic exposure from reproduction to organism maintenance, as previously advocated. This finding may provide the basis for a deeper exploration of the potential population-level effects of nanosized polystyrene particles. Overall, this study suggests that a low concentration of PS NPs may induce mild stress in crayfish, and sheds light on molecular pathways possibly involved in nanoplastic toxicity. In Chapter 3 we examined the underlying mechanism of NPs toxicity in a sensitive early developmental stage of a key marine invertebrate species, the bivalve Mytilus galloprovincialis
L’importanza dell’elaborazione statistica nella valutazione del pericolo potenziale da organoclorurati nella stenella striata (Stenella coeruleoalba) del Mar Mediterraneo
No full textS.T.R.E.S.S. (Statistical Toxicological Risk Elaboration System in Stenella coeruleoalba) from organochlorine compounds (OCs): white (no hazard) or red (emergency) code?
No full textMERCURY LEVELS IN SEVERAL SPECIES OF CETACEANS IN THE WORLD: A REVIEW
No full textThis review summarizes the significant amount of data which was published on mercury (Hg) in cetacean species all over
the world, since the first manuscript was printed in 1971 regarding the Hg in a Pacific pilot whale stranded in San Clemente
Island (California - USA) (Hall et al., 1971). The aim of this paper is to provide a snapshot on existing peer-reviewed
papers and technical reports on levels and spatial and temporal trends of this contaminant in different species of cetaceans,
and provide an initial evaluation on which species should be considered more at risk for mercury and in what water basins
Monk seals (Monachus monachus) in the Mediterranean Sea: The threat of organochlorine contaminants and polycyclic aromatic hydrocarbons
No full textThe Mediterranean monk seal (Monachus monachus) is an emblematic species of conservation concern. Anthropogenic pressures have led to severe population declines and significant fragmentation of the remaining populations. Because of their close relationship with coastal areas, Mediterranean monk seals may be potentially exposed to pollution from agricultural sources, as well as from oil tanker spills. Although monitoring of pollution has long been considered a priority for this species, data on monk seal contamination levels are scarce. In this study, 55 blubber samples of all genders and age classes collected during necropsies (1995-2013) from seals of the Eastern Mediterranean subpopulation were analyzed for organochlorine compounds (OCs), i.e., hexachlorobenzene (HCB), polychlorinated biphenyls (PCBs) and dichlorodiphenyltrichloroethane (DDTs), and polycyclic aromatic hydrocarbons (PAHs). Overall, PCBs > DDTs ≫ PAHs > HCB in all samples. Results showed a significant downward trend over the 19-year period for DDTs and HCB. No marked pattern was found for PAHs, even though relative abundance of cancerogenic PAH fraction rose in recent years. PCB levels in subadult specimens increased noticeably over time despite worldwide ban. Our findings did not suggest recent releases of DDT or new pesticides (e.g., Dicofol) in the environment, but may indicate an improper disposal of ancient storages of PCBs or a remobilization from reservoirs. OC levels exceeded thresholds that are commonly associated with immunosuppression and reproductive impairment in other pinnipeds. Hence, OCs could be responsible of potential toxicological effects in this subpopulation. This study represents the first report on PAH and one of the few reports on OC bioaccumulation in Mediterranean monk seals. Based on the levels found in the blubber of monk seals from the Eastern Mediterranean, and given the known harmful effects associated to the prolonged exposure to these substances and the reduced long-term expectations of species recovery, regular monitoring is advocated
Orally administered nano-polystyrene caused vitellogenin alteration and oxidative stress in the Red Swamp Crayfish (Procambarus clarkii)
No full textNanoplastics (≤100 nm) represent the smallest fraction of plastic litter and may result in the aquatic environment as degradation products of larger plastic material. To date, few studies focused on the interactions of micro- and nanoplastics with freshwater Decapoda. The red swamp crayfish (Procambarus clarkii, Girard, 1852) is an invasive species able to tolerate highly perturbed environments. As a benthic opportunistic feeder, this species may be susceptible to plastic ingestion. In this study, adult P. clarkii, at intermolt stage, were exposed to 100 μg of 100 nm carboxylated polystyrene nanoparticles (PS NPs) through diet in a 72h acute toxicity test. An integrated approach was conceived to assess the biological effects of PS NPs, by analyzing both transcriptomic and physiological responses. Total hemocyte counts, basal and total phenoloxidase activities, glycemia and total protein concentration were investigated in crayfish hemolymph at 0h, 24h, 48h and 72h from PS NPs administration to evaluate general stress response over time. Differentially expressed genes (DEGs) in the hemocytes and hepatopancreas were
analyzed to ascertain the response of crayfish to PS NP challenge after 72h. At a physiological level, crayfish were able to compensate for the induced stress, not exceeding generic stress thresholds. The RNA-Sequencing analysis revealed the altered expression of few genes involved in immune response, oxidative stress, gene transcription and translation, protein degradation, lipid metabolism, oxygen demand, and reproduction after PS NPs exposure. This study suggests that a low concentration of PS NPs may induce mild stress in crayfish, and sheds light on molecular pathways possibly involved in nanoplastic toxicity
The Antarctic Scallop <i>Adamussium colbecki</i> Is Unable to Transcriptomically Respond to Captivity and Moderate Thermal Stress
No full textAdamussium colbecki is a scallop endemic of the Antarctic Ocean, the only modern survivor of the Adamussiini tribe and one of the few bivalves living in polar environments. Compared with other Antarctic animals, very little is known concerning the evolutionary adaptations which allow this species to thrive at sub-zero temperatures. Due to its local abundance and sensitivity to environmental changes, A. colbecki is an interesting model for studying the effects of pollution and climate change in the Antarctic Ocean. Here, we report, for the first time, the application of transcriptomic tools to the study of the effects of a short-to-medium term exposure to a +1.5 °C water temperature increase on three tissues. Although this approach did not highlight any significant change in response to thermal stress, we observed slight alterations in energetic metabolism and nutrient adsorption in the digestive gland, most likely linked with stabling in experimental tanks. The results of our study suggest that A. colbecki may be particularly vulnerable to the effects of climate change due to its complete inability to adapt to temperature increase at the transcriptomic level
First assessment of organochlorine compounds levels in sperm whales (Physeter macrocephalus) stranded in the Canary Islands (Atlantic Ocean) and a comparison with the Mediterranean Sea specimens
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