38 research outputs found

    Ecology and biology of the Antarctic giant fish Dissostichus mawsoni (Pisces, Nototheniidae): reproduction, trophic role and migrations in the Ross Sea region

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    Three different studies have been implemented to fill gaps in the knowledge of the Antarctic toothfish (Dissostichus mawsoni) life cycle in the Ross Sea. First, presence, abundance and size distribution of toothfish in the shelf, in areas periodically covered by sea ice, were investigated by means of Baited Remote Underwater Video systems (BRUVs), an emerging technology never employed before in such kind of habitat. The study was developed from 2015 to 2018 in McMurdo Sound and Terra Nova Bay, it highlighted the efficacy of the methodology for investigating the species, recording dozens of fish of different sizes. We started to make some inferences on how environmental variables influence the distribution of the toothfish in shelf areas, but even more important, we established a working protocol useful for future works. The second section has been focused on the Second Winter Survey conducted in September-October 2019 onboard of a New Zealand fishing vessel with the aim to investigate toothfish reproductive biology, its spawning period and the eggs development and dispersion. The results obtained, combined with those from the First Winter Survey conducted in June-July 2016, allowed to have for the first time a picture of Antarctic toothfish reproduction: the spawning occurs in a wide area in correspondence of the Pacific Antarctic Ridge, it happens in the middle of the winter, and eggs set during all their development in the surface layer of the water column. The last part of the work put light on the fate of toothfish after spawning, a question arose from the observation of the high percentage of sensibly debilitated individuals (named \u201caxe handle\u201d) in the breeding ground. Samples of muscles from six individuals (two \u201caxe handle\u201d and two regular from the breeding area, and two regular from the shelf) were investigated with regard to lipid distribution and composition. The analysis led us to reason on lipid mobilization and usage as energy reserve and/or for neutral buoyancy for reproductive migration, how consistent is their depletion and if toothfish actively feed in the northern area. Different hypotheses on what could cause the frequent poor condition after-spawning and its potential consequences have been illustrated, with the aim to give cues for future insights

    A new record and biological evidence supporting the establishment of Beryx splendens (Actinopterygii: Beryciformes: berycidae) in the western Mediterranean basin

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    A new specimen of splendid alfonsino, Beryx splendens Lowe, 1834, was caught by trawling in July 2016 in the Ligurian Sea at the depth of 350 m, in the proximity of a submarine canyon. It represents the 10th documented record of B. splendens in the Mediterranean. Because of the rarity of the records in the basin, there could be doubts whether to consider or not such species as established in the area. However, some fndings may support the hypothesis of the possible establishment of the species in the Mediterranean Sea. For example, the stomach of the specimen was nearly full, with rests of one crustacean decapod, one fsh, and some cephalopods, which are commonly reported prey items for the species. Macroscopic observation and histological analysis of the gonads revealed that the specimen was a male in an advanced stage of gonadal development. Finally, the coherence of habitat type and prey items with that of extra-Mediterranean populations coupled with gonadal maturation consistent with the observations on other specimens caught in the Mediterranean

    The Arrangement of the Peripheral Olfactory System of Pleuragramma antarcticum: A Well-Exploited Small Sensor, an Aided Water Flow, and a Prominent Effort in Primary Signal Elaboration

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    The olfactory system is constituted in a consistent way across vertebrates. Nasal structures allow water/air to enter an olfactory cavity, conveying the odorants to a sensory surface. There, the olfactory neurons form, with their axons, a sensory nerve projecting to the telencephalic zone\u2014named the olfactory bulb. This organization comes with many different arrangements, whose meaning is still a matter of debate. A morphological description of the olfactory system of many teleost species is present in the literature; nevertheless, morphological investigations rarely provide a quantitative approach that would help to provide a deeper understanding of the structures where sensory and elaborating events happen. In this study, the peripheral olfactory system of the Antarctic silverfish, which is a keystone species in coastal Antarctica ecosystems, has also been described, employing some quantitative methods. The olfactory chamber of this species is connected to accessory nasal sacs, which probably aid water movements in the chamber; thus, the head of the Antarctic silverfish is specialized to assure that the olfactory organ keeps in contact with a large volume of water\u2014even when the fish is not actively swimming. Each olfactory organ, shaped like an asymmetric rosette, has, in adult fish, a sensory surface area of about 25 mm2, while each olfactory bulb contains about 100,000 neurons. The sensory surface area and the number of neurons in the primary olfactory brain region show that this fish invests energy in the detection and elaboration of olfactory signals and allow comparisons among different species. The mouse, for example\u2014which is considered a macrosmatic vertebrate\u2014has a sensory surface area of the same order of magnitude as that of the Antarctic silverfish, but ten times more neurons in the olfactory bulb. Catsharks, on the other hand, have a sensory surface area that is two orders of magnitude higher than that of the Antarctic silverfish, while the number of neurons has the same order of magnitude. The Antarctic silverfish is therefore likely to rely considerably on olfaction

    Phthalate esters (PAEs) concentration pattern reflects dietary habitats (δ13C) in blood of Mediterranean loggerhead turtles (Caretta caretta)

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    Phthalic acid esters (PAEs) are classified as endocrine disruptors, but it remains unclear if they can enter the marine food-web and result in severe health effects for organisms. Loggerhead turtles (Caretta caretta) can be chronically exposed to PAEs by ingesting plastic debris, but no information is available about PAEs levels in blood, and how these concentrations are related to diet during different life stages. This paper investigated, for the first time, six PAEs in blood of 18 wild-caught Mediterranean loggerhead turtles throughout solid-phase extraction coupled with gas chromatography-ion trap/mass spectrometry. Stable isotope analyses of carbon and nitrogen were also performed to assess the resource use pattern of loggerhead turtles. DEHP (12-63 ng mL(-1)) and DBP (6-57 ng mL(-1)) were the most frequently represented PAEs, followed by DiBP, DMP, DEP and DOP. The total PAEs concentration was highest in three turtles (124-260 ng mL(-1)) whereas three other turtles had concentrations below the detection limit. PAEs were clustered in three groups according to concentration in all samples: DEHP in the first group, DBP, DEP, and DiBP in the second group, and DOP and DMP in the third group. The total phthalates concentration did not differ between large-sized (96.3 +/- 86.0 ng mL(-1)) and small-sized (67.1 +/- 34.2 ng mL(-1)) turtles (p < 0.001). However, DMP and DEP were found only in large-sized turtles and DiBP and DBP had higher concentrations in large-sized turtles. On the other hand, DEHP and DOP were found in both small- and large-sized turtles with similar concentrations, i.e. ~ 21.0/32.0 ng mL(-1) and ~ 7(.1)/9.9 ng mL(-1), respectively. Winsored robust models indicated that delta C-13 is a good predictor for DBP and DiBP concentrations (significant Akaike Information criterion weight, AIC(wt)). Our results indicate that blood is a good matrix to evaluate acute exposure to PAEs in marine turtles. Moreover, this approach is here suggested as a useful tool to explain the internal dose of PAEs in term of dietary habits (delta C-13), suggesting that all marine species at high trophic levels may be particularly exposed to PAEs, despite their different dietary habitats and levels of exposure

    Prolonged higher dose methylprednisolone vs. conventional dexamethasone in COVID-19 pneumonia: a randomised controlled trial (MEDEAS)

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    Dysregulated systemic inflammation is the primary driver of mortality in severe COVID-19 pneumonia. Current guidelines favor a 7-10-day course of any glucocorticoid equivalent to dexamethasone 6 mg·day-1. A comparative RCT with a higher dose and a longer duration of intervention was lacking

    How future surgery will benefit from SARS-COV-2-related measures: a SPIGC survey conveying the perspective of Italian surgeons

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    COVID-19 negatively affected surgical activity, but the potential benefits resulting from adopted measures remain unclear. The aim of this study was to evaluate the change in surgical activity and potential benefit from COVID-19 measures in perspective of Italian surgeons on behalf of SPIGC. A nationwide online survey on surgical practice before, during, and after COVID-19 pandemic was conducted in March-April 2022 (NCT:05323851). Effects of COVID-19 hospital-related measures on surgical patients' management and personal professional development across surgical specialties were explored. Data on demographics, pre-operative/peri-operative/post-operative management, and professional development were collected. Outcomes were matched with the corresponding volume. Four hundred and seventy-three respondents were included in final analysis across 14 surgical specialties. Since SARS-CoV-2 pandemic, application of telematic consultations (4.1% vs. 21.6%; p < 0.0001) and diagnostic evaluations (16.4% vs. 42.2%; p < 0.0001) increased. Elective surgical activities significantly reduced and surgeons opted more frequently for conservative management with a possible indication for elective (26.3% vs. 35.7%; p < 0.0001) or urgent (20.4% vs. 38.5%; p < 0.0001) surgery. All new COVID-related measures are perceived to be maintained in the future. Surgeons' personal education online increased from 12.6% (pre-COVID) to 86.6% (post-COVID; p < 0.0001). Online educational activities are considered a beneficial effect from COVID pandemic (56.4%). COVID-19 had a great impact on surgical specialties, with significant reduction of operation volume. However, some forced changes turned out to be benefits. Isolation measures pushed the use of telemedicine and telemetric devices for outpatient practice and favored communication for educational purposes and surgeon-patient/family communication. From the Italian surgeons' perspective, COVID-related measures will continue to influence future surgical clinical practice

    The role of immune suppression in COVID-19 hospitalization: clinical and epidemiological trends over three years of SARS-CoV-2 epidemic

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    Specific immune suppression types have been associated with a greater risk of severe COVID-19 disease and death. We analyzed data from patients >17 years that were hospitalized for COVID-19 at the “Fondazione IRCCS Ca′ Granda Ospedale Maggiore Policlinico” in Milan (Lombardy, Northern Italy). The study included 1727 SARS-CoV-2-positive patients (1,131 males, median age of 65 years) hospitalized between February 2020 and November 2022. Of these, 321 (18.6%, CI: 16.8–20.4%) had at least one condition defining immune suppression. Immune suppressed subjects were more likely to have other co-morbidities (80.4% vs. 69.8%, p < 0.001) and be vaccinated (37% vs. 12.7%, p < 0.001). We evaluated the contribution of immune suppression to hospitalization during the various stages of the epidemic and investigated whether immune suppression contributed to severe outcomes and death, also considering the vaccination status of the patients. The proportion of immune suppressed patients among all hospitalizations (initially stable at <20%) started to increase around December 2021, and remained high (30–50%). This change coincided with an increase in the proportions of older patients and patients with co-morbidities and with a decrease in the proportion of patients with severe outcomes. Vaccinated patients showed a lower proportion of severe outcomes; among non-vaccinated patients, severe outcomes were more common in immune suppressed individuals. Immune suppression was a significant predictor of severe outcomes, after adjusting for age, sex, co-morbidities, period of hospitalization, and vaccination status (OR: 1.64; 95% CI: 1.23–2.19), while vaccination was a protective factor (OR: 0.31; 95% IC: 0.20–0.47). However, after November 2021, differences in disease outcomes between vaccinated and non-vaccinated groups (for both immune suppressed and immune competent subjects) disappeared. Since December 2021, the spread of the less virulent Omicron variant and an overall higher level of induced and/or natural immunity likely contributed to the observed shift in hospitalized patient characteristics. Nonetheless, vaccination against SARS-CoV-2, likely in combination with naturally acquired immunity, effectively reduced severe outcomes in both immune competent (73.9% vs. 48.2%, p < 0.001) and immune suppressed (66.4% vs. 35.2%, p < 0.001) patients, confirming previous observations about the value of the vaccine in preventing serious disease

    D1.1 HYBRIS Specifications and Requirements

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    To respond to the need of flexible energy storage systems, able to provide both power and energy services, Hybris project proposes the integration of an organic redox flow (ORFB) battery with a lithium titanate oxide (LTO) one. Before starting with the design development (WP2), a clear picture of the current available technologies is necessary to address the integration process towards the most appropriate and feasible way. In this document, the requirements and specifications of both LTO and ORFB batteries are analysed, in terms of electrical, electronics, communication, and mechanical characteristics. Moreover, since the hybrid system will perform not only services from the owner point of view, but it will be designed to provide energy services to external requests (DSO), following the paradigm of “Energy as a Service” (EaaS), particular attention will be paid to the requirements for the interoperability. Finally, first assumptions on the technical hybridization and of the overall performance of the hybrid are part of this report

    First records of Chionodraco hamatus nests in coastal areas of Terra Nova Bay (Ross Sea): a potential nesting area for the species?

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    Nests of the icefish Chionodraco hamatus were documented for the first time at about 500 m depth at Terra Nova Bay (Victoria Land, western Ross Sea), in an area included in the Antarctic Specially Protected Area (ASPA) No. 173 within the world's largest established marine area, the Ross Sea Region Marine Protected Area (RSRMPA). Nest building and egg guarding are common parental care behaviours in the Antarctic icefishes (Channichthyidae). Prior to this study, nest building behaviour for C. hamatus was observed only in aquarium experiments. Here we report on the observation of five nests of C. hamatus by remote underwater video systems in November 2021, during an Italian Antarctic expedition. The nests, consisting of gravel and small stones, were circular and bowl-shaped with a consistent diameter of about 30–40 cm. Nest building behaviour, with the icefish individual alternating radial turns in clockwise and counter-clockwise movements was also recorded in situ for the first time. The presence of icefish nests, as well as biotic and abiotic features of the locality, suggest the existence of a C. hamatus nesting area. If confirmed, the occurrence of an icefish nesting area in Silverfish Bay would further strengthen the ecological value of the ASPA 173. Furthermore, documenting nesting icefish in nearshore coastal areas of the RSRMPA reinforces the relevance of the MPA itself and provides an important focus for future research and monitoring in the area
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