175 research outputs found
Placogorgia coronata first documented record in Italian waters: Use of trawl bycatch to unveil vulnerable deep-sea ecosystems
No full textDespite the pluri-decennial history of bottom trawling monitoring in the Italian Sea, limited attention has been given to the study of cold water corals (CWCs) present in the bycatch. As a result, trawl samples still hold a great potential to reveal information about deep-water biodiversity. The rare Mediterranean CWC species Placogorgia coronata was repeatedly found in the bottom trawl discards of the red shrimp fishery in Santa Margherita Ligure (Ligurian Sea). The supposed rarity of this species is strongly biased by taxonomic problems within the genus as well as by the limited exploration of these deep habitats. Scientific literature as well as remotely operated vehicle surveys highlighted the presence, in the investigated trawled area, of a dead white coral framework, supporting the hypothesis that the CWC studied, probably thriving on coral rubble, occurs here due to the natural protection to trawling offered by the coral matrix. Trawlers, however, may accidentally affect these secondary hard grounds, as demonstrated by the discard content. The long-term monitoring of the catches highlighted a removal rate of up to one colony every two trawling operations; based on the anecdotal fishing effort in this area and the status of the discarded specimens, it is possible to estimate an average catch rate of about 18 live colonies per year per fisherman. The occurrence of rare CWC species with low resilience to fishing disturbance is among the required information for the identification of fishing restriction zones designed to protect deep vulnerable marine ecosystems
System level design and power analysis of architectures for SATD calculus in the H.264/AVC
No full textFirst record of Bombina variegata (Linnaeus, 1758) in a cave environment
No full textSeveral species of amphibians are known to inhabit
subterranean habitats. While some species are obligatory
cave-dwelling (e.g., Proteus anguinus Laurenti, 1768),
others tend to use caves only for limited periods of their
lives (Peck, 1974; Romero, 2009). At least 17 species of
amphibians that belong to the Italian herpetofauna have
on occasion been found in caves or other underground
spaces and several of them occasionally breed in
subterranean sites. Here we provide the first evidence
of a population of yellow-bellied toads (Bombina
variegata) exploiting a subterranean habita
Unveiling the deep biodiversity of the Janua Seamount (Ligurian Sea): first Mediterranean sighting of the rare Atlantic bamboo coral Chelidonisis aurantiaca Studer, 1890
No full textSeamounts represent ecologically important marine environments and undeniably play a crucial role in the functioning of the deep-sea ecosystems, thanks primarily to their contribution in supporting offshore benthic and pelagic biodiversity. In the last decades, these features have received attention in all oceans of the world, but they were relatively overlooked in the Mediterranean Sea. In particular, the Ligurian Sea hosts six major structures, whose summits, ranging from 150 to nearly 2000 m depth, are virtually unknown from the biological point of view. The summit region of the Janua Seamount, located approximately at 30 nautical miles off the harbour of Genoa at 810 m depth, was explored for the first time using Remotely Operated Vehicles. The sea bed topography is characterized by a heterogeneous hard bottom, dominated by sub-fossil thanatocoenoses of Lophelia pertusa (Linnaeus, 1758) covered in a thick Ferrous-Manganese crust, and colonized by a scattered bathyal assemblage dominated by hexactinellids and benthic cnidarians showing a distinct regionalization around the summit. Cnidarians observed in this site include a rare Atlantic bamboo coral (Isididae, Chelidonisis aurantiaca Studer, 1890), described herein for the first time for the Mediterranean Basin. These findings provide new information on the biogeographic patterns of colonization of the bathyal Mediterranean fauna but also highlight the large knowledge gap that still exists for deep-sea biodiversity of this basin
Fragmentation, re-attachment ability and growth rate of the Mediterranean black coral Antipathella subpinnata
No full textCnidarians are known for their simple body plan and their complex life cycles, involving high regenerative and asexual-reproduction potential. In particular, several asexual reproductive strategies are known for anthozoans, including fragmentation, carried out by tentacles, by groups of polyps or by portions of colonies. Here, we report the first observation of an extensive event of fragmentation in the Mediterranean black coral species Antipathella subpinnata (Antipatharia: Myriopathidae) in rearing conditions. Once detached, fragments lose their polarity and new anchorages are rapidly created with polyps and cnidocysts participating in the adhesion phases. Multiple attachments are frequently observed, with new skeletal plates produced through the expansion of spines. Dendritic spines gradually arise on these new plates. Fragments start to generate numerous new branchlets orientating upward and with a fixed arrangement. In 7 months of monitoring, fragments revealed fast growth rates, up to 1.85 and 1.58 cm month −1 , for the whole fragments and new branchlets, respectively. Attachment of black coral fragments has never been recorded in the field; nevertheless, frequent adhesions observed in aquaria suggest that fragmentation could be a successful reproductive strategy in these anthozoans
Local structure of liquid and undercooled liquid Cu probed by x-ray absorption spectroscopy
No full textIn this work we report about a recent XAS (x-ray absorption spectroscopy) experiment aimed to study the local structure of liquid and undercooled copper, a typical close-packed liquid metal, under high-pressure conditions. In our study we have obtained new experimental data of liquid Cu under high pressure and high-temperature conditions using synchrotron radiation at the ESRF and a large-volume Paris-Edinburgh cell. We have studied the extension of the undercooling region as well as possible modifications of the local structure as a function of pressure, using XAS data-analysis. Liquid copper has been undercooled up to 300°C below the melting point at high pressures up to 3.3 GPa
Local Conditions Influence the Prokaryotic Communities Associated With the Mesophotic Black Coral Antipathella subpinnata
No full textBlack corals are important habitat-forming species in the mesophotic and deep-sea zones of the world’s oceans because of their arborescent colony structure and tendency to form animal forests. Although we have started unraveling the ecology of mesophotic black corals, the importance of the associated microbes to their health has remained unexplored. Here, we provide in-depth assessments of black coral-microbe symbioses by investigating the spatial and temporal stability of these associations, and make comparisons with a sympatric octocoral with similar colony structure. To this end, we collected samples of Antipathella subpinnata colonies from three mesophotic shoals situated along the Ligurian Coast of the Mediterranean Sea (Bordighera, Portofino, Savona) in the spring of 2017. At the Portofino shoal, samples of A. subpinnata and the gorgonian Eunicella cavolini were collected in November 2016 and May 2017. Bacterial communities were profiled using 16S rRNA gene amplicon sequencing. The bacterial community of E. cavolini was consistently dominated by Endozoicomonas. Contrastingly, the black coral microbiome was more diverse, and was primarily composed of numerous Bacteroidetes, Alpha- and Gammaproteobacterial taxa, putatively involved in all steps of the nitrogen and sulfur cycles. Compositional differences in the A. subpinnata microbiome existed between all locations and both time points, and no phylotypes were consistently associated with A. subpinnata. This highlights that local conditions may influence the bacterial community structure and potentially nutrient cycling within the A. subpinnata holobiont. But it also suggests that this coral holobiont possesses a high degree of microbiome flexibility, which may be a mechanism to acclimate to environmental change
Inflamm-aging microRNAs may integrate signals from food and gut microbiota by modulating common signalling pathways
No full textHuman gut microbiota, which comprises an extremely diverse and complex community of microorganisms inhabiting the intestinal tract, may be associated with inflammation and age-related chronic health conditions. However, the mechanism underlying this association is only recently beginning to emerge. Transfer and modulation of gene expression by diet-derived microRNAs (miRs) in mammals might be involved in this communication. Through a bioinformatics approach, using on line tools and repositories, we searched for evidences that food-containing miRs, actually involved in the modulation of the inflammatory process, (inflamma-miRs), may contribute to mediate the anti-inflammatory effects exerted by some foods through the modulation of aging-related pathways and gut microbiota composition in a bidirectional communication. Supported by a "Pubmed" search and our previous research, a trio of experimentally validated inflamma-miRs were considered: miR-155, miR-146a and miR-21. Our in silico study supports the hypothesis that these inflamma-miRs could modulate some pathways, such as lysine degradation and lengthening of fatty acids which are involved in the modulation of microbiota composition, i.e. prevotella, ruminococcus and oscillibacter and vice versa. Food homologues to human miR-21, miR-155 and miR-146a were found in cow fat, cow milk, and eggs suggesting that they may be able of targeting, and probably exacerbating, inflammation related pathways. If these data will be experimentally validated, they will further support the relevance of a nutraceutical approach for a healthy aging
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