255 research outputs found
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Marine plastic debris emits a keystone infochemical for olfactory foraging seabirds.
Plastic debris is ingested by hundreds of species of organisms, from zooplankton to baleen whales, but how such a diversity of consumers can mistake plastic for their natural prey is largely unknown. The sensory mechanisms underlying plastic detection and consumption have rarely been examined within the context of sensory signals driving marine food web dynamics. We demonstrate experimentally that marine-seasoned microplastics produce a dimethyl sulfide (DMS) signature that is also a keystone odorant for natural trophic interactions. We further demonstrate a positive relationship between DMS responsiveness and plastic ingestion frequency using procellariiform seabirds as a model taxonomic group. Together, these results suggest that plastic debris emits the scent of a marine infochemical, creating an olfactory trap for susceptible marine wildlife
A comparative analysis of aquatic and polyethylene-associated antibiotic-resistant microbiota in the mediterranean sea
In this study, we evaluated the microbiome and the resistome profile of water and fragments of polyethylene (PE) waste collected at the same time from a stream and the seawater in a coastal area of Northwestern Sicily. Although a core microbiome was determined by sequencing of the V3–V4 region of the bacterial 16S rDNA gene, quantitative differences were found among the microbial communities on PE waste and the corresponding water samples. Our findings indicated that PE waste contains a more abundant and increased core microbiome diversity than the corresponding water samples. Moreover, PCR analysis of specific antibiotic resistance genes (ARGs) showed that PE waste harbors more ARGs than the water samples. Thus, PE waste could act as a carrier of antibiotic-resistant microbiota, representing an increased danger for the marine environment and living organisms, as well
Occurrence of Antibiotic Resistance in the Mediterranean Sea
Seawater could be considered a reservoir of antibiotic-resistant bacteria and antibiotic resistance genes. In this communication, we evaluated the presence of bacterial strains in seawater collected from different coasts of Sicily by combining microbiological and molecular methods. Specifically, we isolated viable bacteria that were tested for their antibiotic resistance profile and detected both antibiotic and heavy metal resistance genes. Both antibiotic-resistant Gram-negative bacteria, Vibrio and Aeromonas, and specific antibiotic resistance genes were found in the seawater samples. Alarming levels of resistance were determined towards cefazolin, streptomycin, amoxicillin/clavulanic acid, ceftriaxone, and sulfamethoxazole/trimethoprim, and mainly genes conferring resistance to β-lactamic and sulfonamide antibiotics were detected. This survey, on the one hand, presents a picture of the actual situation, showing the pollution status of the Tyrrhenian coast of Sicily, and, on the other hand, can be considered as a baseline to be used as a reference time for future analysis
Vibrational spectra and structures of bare and Xe-tagged cationic Si<sub>n</sub>O<sub>m</sub><sup>+</sup> clusters
Vibrational spectra of Xe-tagged cationic silicon oxide clusters SinOm+ with n = 3–5 and m = n, n ± 1 in the gas phase are obtained by resonant infrared multiple photon dissociation (IRMPD) spectroscopy and density functional theory calculations. The SinOm+ clusters are produced in a laser vaporization ion source and Xe complexes are formed after thermalization to 100 K. The clusters are subsequently irradiated with tunable light from an IR free electron laser and changes in the mass distribution yield size-specific IR spectra. The measured IRMPD spectra are compared to calculated linear IR absorption spectra leading to structural assignments. For several clusters, Xe complexation alters the energetic order of the SinOm+ isomers. Common structural motifs include the Si2O2 rhombus, the Si3O2 pentagon, and the Si3O3 hexagon
Presence and biodistribution of perfluorooctanoic acid (PFOA) in Paracentrotus lividus highlight its potential application for environmental biomonitoring
The first determination of presence and biodistribution of PFOA in ninety specimens of sea urchin Paracentrotus lividus from two differently contaminated sites along Palermo’s coastline (Sicily) is reported. Analyses were performed on the sea urchins’ coelomic fluids, coelomocytes, gonads or mixed organs, as well as on seawater and Posidonia oceanica leaves samples from the collection sites. PFOA concentration ranged between 1 and 13 ng/L in seawater and between 0 and 794 ng/g in P. oceanica. The analyses carried out on individuals of P. lividus from the least polluted site (A) showed PFOA median values equal to 0 in all the matrices (coelomic fluid, coelomocytes and gonads). Conversely, individuals collected from the most polluted site (B) showed median PFOA concentrations of 21 ng/g in coelomic fluid, 153 ng/g in coelomocytes, and 195 ng/g in gonads. Calculated bioconcentration factors of log10BCF > 3.7 confirmed the very bioaccumulative nature of PFOA. Significant correlations were found between the PFOA concentration of the coelomic fluid versus the total PFOA concentration of the entire sea urchin. PERMANOVA (p = 0.001) end Welch's t-test (p < 0.001) analyses showed a difference between specimens collected from the two sites highlighting the potential application of P. lividus as sentinel species for PFOA biomonitoring
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Search for novel diagnostic biomarkers of prostate inflammation-related disorders: role of transglutaminase isoforms as potential candidates
Investigations on prostate inflammation-related disorders, including acute and chronic prostatitis, chronic pelvic pain syndrome, benign prostate hyperplasia (BPH), and prostate cancer (PCa), are still ongoing to find new, accurate, and noninvasive biomarkers for a differential diagnosis of those pathological conditions sharing some common macroscopic features. Moreover, an ideal biomarker should be useful for risk assessment of prostate inflammation progression to more severe disorders, like BPH or PCa, as well as for monitoring of treatment response and prognosis establishment in carcinoma cases. Recent literature evidence highlighted that changes in the expression of transglutaminases, enzymes that catalyze transamidation reactions leading to posttranslational modifications of soluble proteins, occur in prostate inflammation-related disorders. This review focuses on the role specifically played by transglutaminases 4 (TG4) and 2 (TG2) and suggests that both isoenzymes hold a potential to be included in the list of candidates as novel diagnostic biomarkers for the above-cited prostate pathological conditions
Is caretta caretta a carrier of antibiotic resistance in the mediterranean sea?
Sea turtles can be considered a sentinel species for monitoring the health of marine ecosystems, acting, at the same time, as a carrier of microorganisms. Indeed, sea turtles can acquire the microbiota from their reproductive sites and feeding, contributing to the diffusion of antibiotic-resistant strains to uncontaminated environments. This study aims to unveil the presence of antibiotic-resistant bacteria in (i) loggerhead sea turtles stranded along the coast of Sicily (Mediterranean Sea), (ii) unhatched and/or hatched eggs, (iii) sand from the turtles’ nest and (iv) seawater. Forty-four bacterial strains were isolated and identified by conventional biochemical tests and 16S rDNA sequencing. The Gram-negative Aeromonas and Vibrio species were mainly found in sea turtles and seawater samples, respectively. Conversely, the Gram-positive Bacillus, Streptococcus, and Staphylococcus strains were mostly isolated from eggs and sand. The antimicrobial resistance profile of the isolates revealed that these strains were resistant to cefazolin (95.5%), streptomycin (43.2%), colistin and amoxicillin/clavulanic acid (34.1%). Moreover, metagenome analysis unveiled the presence of both antibiotic and heavy metal resistance genes, as well as the mobile element class 1 integron at an alarming percentage rate. Our results suggest that Caretta caretta could be considered a carrier of antibiotic-resistant genes
Representing Ecological Network Specifications with Semantic Web Techniques
Ecological Networks (ENs) are a way to describe the structures of existing real ecosystems and to plan their
expansion, conservation and improvement. In this work, we present a model to represent the specifications for
the local planning of ENs in a way that can support reasoning, e.g., to detect violations within new proposals
of expansion, or to reason about improvements of the networks. Moreover, we describe an OWL ontology
for the representation of ENs themselves. In the context of knowledge engineering, ENs provide a complex,
inherently geographic domain that demands for the expressive power of a language like OWL augmented with
the GeoSPARQL ontology to be conveniently represented. More importantly, the set of specification rules
that we consider (taken from the project for a local EN implementation) constitute a challenging problem for
representing constraints over complex geographic domains, and evaluating whether a given large knowledge
base satisfies or violates them
Il progetto OnToMap: costruire conoscenza territoriale attraverso l’uso di un’applicazione ICT
Il progetto OnToMap - Mappe di Comunità 3.0 nasce con l'obiettivo di sviluppare uno strumento capace di rispondere alle esigenze informative dei cittadini e di favorire il confronto tra questi e gli amministratori locali, creando uno spazio in cui le relazioni tra gli attori si articolino su una base cartografica e siano favorite dall'uniformità di linguaggio garantita dall'ontologia territoriale, nucleo della piattaforma. Il progetto si sviluppa a partire dalla costruzione di un'ontologia per la rappresentazione della conoscenza territoriale, realizzata attraverso l'individuazione dei concetti che compongono il territorio e l'identificazione delle relazioni semantiche che intercorrono tra essi. In questa prospettiva sono individuate le dimensioni costitutive del territorio, che tengono conto delle componenti ambientali, urbanistiche, culturali e sociali. Il principale risultato del progetto è l'applicazione web OnToMap per la gestione di mappe di comunità interattive. OnToMap è disponibile online, anche in versione mobile, e offre agli utenti internet un punto di vista integrato sul territorio, arricchibile secondo un modello di crowdsourcing e navigabile secondo criteri di ricerca semantici. La ricerca, tuttora in corso, si concentra su una sperimentazione dell'applicazione con lo scopo di produrre mappe partecipate su porzioni territoriali puntuali all'interno del contesto Torinese. In futuro OnToMap sarà arricchito, al fine di contribuire all'empowerment della cittadinanza, con nuove funzionalità ; per esempio sarà possibile l'inserimento di nuovi dati da parte dell'utente, l'effettuazione di ricerche di informazioni per parola chiave, il supporto al ragionamento sui vincoli normativi che regolano il territorio e la creazione di forum di discussion
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