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Acoustic noise levels were measured in the Gulf of Catania (Ionian Sea) from July 2012 to May 2013 by a low frequency (< 1000 Hz) hydrophone, installed on board the NEMO-SN1 multidisciplinary observatory. NEMO-SN1 is a cabled node of EMSO-ERIC, which was deployed at a water depth of 2100 m, 25 km off Catania. The study area is characterized by the proximity of mid-size harbors and shipping lanes. Measured noise levels were correlated with the passage of ships tracked with a dedicated AIS antenna. Noise power was measured in the frequency range between 10 Hz and 1000 Hz. Experimental data were compared with the results of a fast numerical model based on AIS data to evaluate the contribution of shipping noise in six consecutive 1/3 octave frequency bands, including the 1/3 octave frequency bands centered at 63 Hz and 125 Hz, indicated by the Marine Strategy Framework Directive (2008/56/EC). [ABSTRACT FROM AUTHOR]

In this paper, we review some results obtained from three one-dimensional stochastic models, which were used to analyze picophytoplankton dynamics in two sites of the Mediterranean Sea. Firstly, we present a stochastic advection–reaction–diffusion model to describe the vertical spatial distribution of picoeukaryotes in a site of the Sicily Channel. The second model, which is an extended version of the first one, is used to obtain the vertical stationary profiles of two groups of picophytoplankton, i.e. Pelagophytes and Prochlorococcus, in the same marine site as in the previous case. Here, we include intraspecific competition of picophytoplanktonic groups for limiting factors, i.e. light intensity and nutrient concentration. Finally, we analyze the spatio-temporal behaviour of five picophytoplankton populations in a site of the Tyrrhenian Sea by using a reaction–diffusion–taxis model. The study is performed, taking into account the seasonal changes of environmental variables, obtained starting from experimental findings. The multiplicative noise source, present in all three models, mimics the random fluctuations of temperature and velocity field. The vertical profiles of chlorophyll concentration obtained from the stochastic models show a good agreement with experimental data sampled in the two marine sites considered. The results could be useful to devise a new class of models based on a stochastic approach and able to predict future changes in biomass primary production. [ABSTRACT FROM AUTHOR]

Abstract: Concentrations of rare earth elements (REE), Y, Th and Sc were recently determined in marine sediments collected using a box corer along two onshore–offshore transects located in the Strait of Sicily (Mediterranean Sea). The REE+Y were enriched in offshore fine-grained sediments where clay minerals are abundant, whereas the REE+Y contents were lower in onshore coarse-grained sediments with high carbonate fractions. Considering this distribution trend, the onshore sediments in front of the southwestern Sicilian coast represent an anomaly with high REE+Y concentrations (mean value 163.4μgg−1) associated to high Th concentrations (mean value 7.9μgg−1). Plot of shale-normalized REE+Y data of these coastal sediments showed Middle REE enrichments relative to Light REE and Heavy REE, manifested by a convexity around Sm–Gd–Eu elements. These anomalies in the fractionation patterns of the coastal sediments were attributed to phosphogypsum-contaminated effluents from an industrial plant, located in the southern Sicilian coast. [ABSTRACT FROM AUTHOR]

Understanding spatio-temporal patterns of top predators can be crucial for evaluating key habitats, assessing the effects of anthropogenic activity and consequently applying suitable management policies. Here, we characterized dolphins acoustic occurrence and interactions with boat presence and noise in the waters of the Sicily Strait. A hydrophone was deployed on an elastic beacon three miles off the coast of south-west Sicily, and recorded continuously for 14 months, from January 2015. Results revealed that packed and train clicks types were the most detected signals, suggesting that animals were especially involved in feeding activity. A regular year-round acoustic presence was recorded, with seasonal variability. Two peaks were detected during the year in August and November, cuncurrently with a possible increase in fish biomass in the area. An abrupt decrease in click detection rate in September coincides with the biological shutdown in 2015 and the shift of fishing vessels offshore, suggesting a possible movement of dolphins following trawlers. Furthermore, dolphins vocalized more during the night-time, probably carrying out movements to and from the coast. Results indicated that dolphins interact with trawlers during mid-morning when an intermediate level of activity was collected, but click detection rate decreased with increasing noise levels at one-third octave bands centered at 250 Hz. Outcomes can help inform conservation efforts and the development of monitoring programmes focused on environmental impact assessments under the EU Marine Strategy Framework Directive. Image 1 • Dolphins acoustic occurrence was characterized in the North –Western Sicily Strait. • A regular year-round presence was recorded, with seasonal and diel variability. • Feeding activity and a strong interaction with trawlers was acoustically detected. • Outcomes can help inform conservation efforts and monitoring programmes in the area. [ABSTRACT FROM AUTHOR]

Highlights • Accelerometer is an efficient tool to monitor the acoustic behaviour of P. elephas. • Low accelerometer sample frequencies don't influence detection of acoustic events. • Low accelerometer sample frequencies increase the error on pulses estimation. • Accelerometer data let to separate acoustic from behavioural events of P. elephas. Abstract The European spiny lobster Palinurus elephas emits sound ("rasp"), moving the base of their antennas, as response to the presence of predator and for interspecific communication. During the last decade, three-axial accelerometers have been used to mainly describe diel activity patterns, circadian rhythms and rate of energy consumption of different lobster species, but these devices can also record sound emission in terms of mechanical vibration of carapace. In order to evaluate the efficiency of accelerometers in recording sound production (rasp events and number of pulses inside each rasp) and in discriminating of that from other behavioural events, accelerometers were used in combination with hydrophone and during mesocosm free ranging conditions. Three-axial accelerometers were able to detect sound production events in P. elephas. All the rasp events (n = 405) recorded with hydrophones were also detected by the accelerometers considering its data sampled at different frequency (from 800 Hz to 12 Hz). However, the detection of the number of pulses within each rasp sound decreased with sampling frequency of accelerometer data (median of predictive error for 800 Hz = 0.33; median of predictive error for 12 Hz = 0.65). During mesocosm free condition, three behavioural categories were identified: walk, tail flip, and rasp, the last with averaged (15.16 ± 3.52 m/s2) and maximum (29.49 ± 9.37 m/s2) values of acceleration significantly higher than the other two. Findings from this study prove that accelerometers register only lobster body vibrations providing a clear signal that is not distorted by other noises in the environment. They also allowed to identify rasps for each tagged lobster, something not possible using hydrophones in both, aquaria or natural habitat. Accelerometer resulted an useful tool to detect behaviours even with low mobility species. Moreover, the possibility to couple accelerometer and other biologging techniques would help to improve our understanding of the behaviour of a large range of free-living species. [ABSTRACT FROM AUTHOR]

Soundscapes are strongly linked with the physical structure and biological features of the habitats and their study can reveal ecological processes of the underwater environment. Objective of this study is to characterize two Mediterranean habitats, the Posidonia oceanica meadow and the sandy bottom, and demonstrate their acoustic diversification basing on their soundscapes. Firstly, the habitats have been compared using two different acoustic metrics, the Power Spectral Density (PSD) and the Acoustic Complexity Index (ACI), measured in different frequency band. Then, the acoustic biological component of the habitats has been identified and characterized: five biological signals were described and their acoustic properties and temporal patterns were defined. Finally, the geophonical and anthropogenic components of the two habitats have been compared. In the low frequency (<0.5 kHz) the sandy habitat showed higher values of PSD and lower values of ACI. From 0.5–24 kHz the greatest values of both parameters were recorded in the Posidonia habitat due to the acoustic activity of snapping shrimps and fishes. The wind speed resulted significantly correlated with PSD from 0.1 to 2 kHz for both habitats, but the correlation is less intense in Posidonia habitat suggesting a noise attenuation phenomenon. The two habitats present biophonical component belonged to different fish species and invertebrates; they showed alternated temporal pattern and different frequency allocation. The Posidonia habitat resulted acoustically richer than sandy habitat, confirming the importance of ecoacoustic method to study ecological processes. Finally, a strong acoustic impact from the anthropogenic component was revealed: it achieves 60% of daytime during the summer, especially in sandy habitat. Results demonstrated not only the possibility to discriminate habitats through the sound information but also the need to protect marine ecosystems from the human noise. [ABSTRACT FROM AUTHOR]

We present data on distribution patterns of living coccolithophores at 18 selected hydrographic stations, and oceanographic measurements collected at 68 stations during the TIR09 cruise carried out on board of R/V Urania in the southern Tyrrhenian Sea (central part of the Mediterranean Sea) during summer 2009. The survey enabled us to provide indications on the structure of calcareous phytoplankton associations in relation to oceanographic parameters and vertical water column stratification. The total number of coccospheres ranged from < 100 cells l − 1 to ~ 6.8 ∗ 10 4 cells l − 1 (mean 8.28 ∗ 10 3 cells l − 1 ). Emiliania huxleyi dominated the assemblages, followed by Gephyrocapsa spp., small placoliths, Calciosolenia spp., Florisphaera profunda , Holococcolithophores spp., Syracosphaera pulchra and Umbellosphaera tenuis . The coccolithophore community showed a typical vertical zonation, with K-strategist taxa in the upper 75 m and the deep community down to 200 m. The local water circulation and summer stratification significantly affected the spatial and vertical distribution of coccolithophores. [ABSTRACT FROM AUTHOR]

The Multi-Beam Echo Sounder (MBES) is a tool that allows getting information about bathymetric, morphological and compositional characteristics of the seabed surface. Although this is still one of the most important features in hydrography, MBES can now also discriminate the acoustic imaging of the water mass by recording sampled reflectivity measurements along each beam. In this paper, two MBES, namely the Kongsberg Simrad EM3002D (300 kHz) and the Reson Seabed8125-H (455 kHz), which are generally employed to study seafloor characteristics, have been used for the identification of fish schools in the water column at very high resolution. In particular, a methodology to identify and analyse fish schools through the Water Column Backscatter (WCB) is presented. This methodology made it possible to obtain a wide variety of fish schools shape in 3-D (in our case, anchovies and sardines), which allowed a first study on the ecological behaviour of the schools according to their shape. All data were collected along with Kongsberg Simrad EK60 scientific echo sounder, allowing also a comparison of different approaches to fish schools identification. The data presented in this paper were collected during two oceanographic surveys within the project MEDIAS (MEDiteranean International Acoustic Survey), Ancheva 2010 and Ancheva 2011. Beyond the mere visualization of school shapes, we also attempted to gain numerical values of the school volumes and to realize a more detailed study of anchovies and sardines school shapes. In line with the current literature, this study showed that there are three main factors influencing the shape of a school, namely the depth of the bottom, the time of the day when data are acquired and the density of individuals in the investigated area. [ABSTRACT FROM AUTHOR]

Trophic ecology of adults of European sardine ( Sardina pilchardus ) and anchovy ( Engraulis encrasicolus ) was examined and compared among various regions of central Mediterranean Sea. Carbon and nitrogen stable isotope analyses (δ 13 C and δ 15 N) were adopted as a tool to determine changes in feeding behaviour of adults of sardines and anchovies. In the study period (summer) a clear geographical pattern was recognized in the isotopic composition of both species, with an increasing trend northward. The highest variations in isotopic signal were linked to the geographical positions of the samples and, especially, between pairs of areas: South Sicily/South Campania and Gulf of Gaeta/South Elba. Higher isotope values were found in the anchovies and sardines caught in northern Tyrrhenian Sea, while lower values were mostly estimated in the southern region. Higher carbon and nitrogen isotopes may reflect a more coastal behaviour of both species, being 13 C-enriched source from benthic primary producers in addition to phytoplankton. Variations in the nitrogen isotope ratio may reflect not only differences in the trophic level of prey species, but also variations in the baseline level of food webs. Our results support the hypothesis that feeding behaviour of both species is directly or indirectly influenced by local factors, or by resource partitioning based on zooplankton size. Findings can supply knowledge needed for improving fish stock management and promoting plans able to take into account also local ecosystem analysis. [ABSTRACT FROM AUTHOR]

Acoustic methods for seafloor mapping have been widely developed over the last decades. In particular, the development of swath bathymetry has allowed the creation of detailed maps of seabed topography and acoustic backscatter data; these data have been used to infer sediment and habitat types. In this paper the capability of Multi-Beam Echo Sounder (MBES) system data to distinguish different seabed types in a site in the Tyrrhenian Sea (Mediterranean) is evaluated; dataset used includes bathymetric data and backscatter intensity, with the support of sediment samples and scuba investigations. The Reson SeaBat 8125 MBES system provides bathymetric and backscatter data. The backscatter data are stored both as Sidescan-like data (intensity values produced by an averaging process) and Snippet data (a time-series of intensity values for each beam). The processing of these acoustic data belongs to a relatively new field of research: the aim of this paper is to show two different processing approaches, and discuss the produced output. The mosaic of images from the Sidescan-like and Snippet data are statistically analyzed, in order to highlight the resolution of the Snippet when dealing with acoustic facies and the correlation existing between granulometric features and the recognized facies. In conclusion, even if no signal appears to be better than the other, it is evident that both Sidescan-like and Snippet data are complementary to a correct interpretation of the seafloor features and can produce a highly detailed acoustic mosaic useful for several scientific areas, including habitat mapping. [ABSTRACT FROM AUTHOR]

Abstract: We present a major, trace and rare earth element characterization of single glass shards from fifteen tephra layers found in the astronomically-tuned KC01B deep-sea core (Ionian Sea, Central Mediterranean-36°15.25′N, 17°34.44′E, 3642 m water depth). KC01B is considered a reference core for the Mediterranean area since it provides a new reliable astronomical tuned timescale for the last 1.112 My (Lourens, 2004). The studied deposits punctuate the marine record in a time span ranging from ca 16 ka to ca 191 ka B.P. encompassing the climatic zones Y, X, W and V. They are related to volcanic activity of the Campania Plain, Aeolian Islands, Mt. Etna and Pantelleria Island. Along with major main markers of the Central Mediterranean area such as Y-1, Y-5, and X-6, astronomically dated at 16.7 ka, 39.1 ka, and 110.5 ka, respectively, the succession contains a number of well preserved deposits which can represent useful inter-archive instruments of correlation. The Campania Plain, in particular, sourced at least nine compositionally homogeneous tephra layers prior to the Campanian Ignimbrite event. The data obtained in this work provide a new detailed analytical reference database for Ionian Sea tephrochronology and for proximal-distal correlation studies. They may help to unravel from the marine record the history of poorly known or unknown explosive activity on land since the middle Pleistocene along with chemical composition, size and dispersal of the products. [Copyright &y& Elsevier]

Abstract: Objective: To determine the efficacy of core decompression (CD) technique combined with recombinant morphogenetic proteins, autologous mesenchymal stem cells (MSCs) and xenograft bone substitute into the necrotic lesion of the femoral head on clinical symptoms and on the progression of osteonecrosis of the femoral head. Patients and methods: A total of 38 patients (40 hips) with early stage osteonecrosis of the femoral head were studied over a 4-year period. Results: CD technique combined with recombinant morphogenetic proteins, autologous MSCs and xenograft bone substitute was associated with a significant reduction in both pain and joint symptoms and reduced the incidence of fractural stages. At 36 months, 33 patients achieved clinical and radiographic healing. Conclusion: This long-term follow-up study confirmed that CD technique combined with recombinant morphogenetic proteins, autologous MSCs and xenograft bone substitute may be an effective treatment for patients with early stage osteonecrosis of the femoral head. [Copyright &y& Elsevier]

Highlights: [•] The Hg evasion flux in the Augusta basin marine boundary layer was examined. [•] The human activity has influenced in the past the marine Hg cycle in the Augusta Bay. [•] The release of Hg from the Augusta Bay is a source of pollution for the Mediterranean. [ABSTRACT FROM AUTHOR]

Abstract: Our study reports on the total mercury (HgT) concentrations measured in the muscles and livers of several benthic, demersal and pelagic fish species caught inside and outside of Augusta Bay (southern Italy), a semi-enclosed marine area, highly contaminated by the uncontrolled (since the 1950s to 1978s) discharge of the largest European petrochemical plant. Mercury levels in fish tissues are discussed with regard to specific habitat, size and/or age of the specimens and HgT distribution in the bottom sediments. Results suggest a still active Hg release mechanism from the polluted sediments to the marine environment. Also, the high HgT concentrations measured in fishes caught in the external area of the bay imply a potential role of Augusta Bay as a pollutant source for the Mediterranean ecosystem. Finally, values of hazard target quotient (THQ) and estimated weekly intake (EWI) demonstrate that consumption of fishes caught inside the bay represents a serious risk for human health. Also, data indicate that intake of fishes caught from the external area of the bay, especially for that concern demersal and benthic species, could be represent a significant component of risk for the local population. [Copyright &y& Elsevier]

Abstract: Trace elements released in the environment during agricultural practices can be incorporated and accumulated in biological fluids and tissues of living organisms. The assessment of these exposures were carried out investigating lanthanide distributions in blood and exoskeleton samples collected from Emys trinacris turtle specimens coming from sites with anthropogenic discharge in western and south Sicily, along migration paths of many bird species from Africa to Europe. The data show a significant (Rxy =0.72; Rxy >0.67; α =0.025) linear relationship between the size of turtle specimens and the lanthanide contents in blood lower than 0.4μgL−1 whereas this relationship disappears in blood with higher lanthanide contents. Comparative evaluations of normalised concentrations show that lanthanides fractionate between blood and exoskeleton inducing antithetical lanthanide patterns therein. These features are more evident in specimens with high lanthanide contents in blood, suggesting that lanthanide accumulations in the exoskeleton can represent the physiological response of E. trinacris to environmental and the further confirmation of relationship occurring between the environmental and the biological fluids. [Copyright &y& Elsevier]

Abstract: Islet transplantation, since the 1990s, has been an example of human cell therapy. Nevertheless, the islet isolation procedure is not completely standardized; in fact, >50% of islet procedures do not eventuate in transplantation due both to the variability of a donor''s pancreas and to the unpredictable efficiency of an enzymatic blend. The enzymes used in pancreas isolation to digest several substrates are extracted from Clostridium histolyticum. In particular, they have strong collagenolytic activity compared with vertebrate collagenases. However, several impediments persist in human islet isolation success, probably owing to the variable composition and concentration of collagenases employed during the digestion phase. For islet isolation processes, neutral proteases play important roles. However, they should be considered to be double-edged swords, contributing to tissue dissociation but, sometimes, decreasing islet yield through fragmentation, breakdown, and inactivation. Protease activities cannot be preciously adjusted in a narrow range, there is no approach to determine the optimal dosage and composition of enzymes for extraction of human islets from the pancreas. At this time, available data on commercial enzymatic activity are not sufficient to predict their efficiency for pancreas digestion; consequently, it is difficult to select enzyme batches. For these reasons, we sought to generate an innovative evaluation assay to select enzymes useful for isolation procedures of pancreatic islets. [Copyright &y& Elsevier]

Abstract: Quantitative analysis of 67 calcareous nannofossil assemblages from surface sediments recovered in a wide area across the Sicily Channel has been carried out in order to improve the interpretation of palaeontological data based on this planktonic group in a key area for Mediterranean palaeoceanographic studies. The investigation focused on three case studies that demonstrate the high potentiality of such a combined approach, taking into account the recent distribution of taxa or groups of taxa on the sea floor and the palaeontological record. The distribution of reworked specimens over the northern Sicily Channel sea floor validates the role of southern Sicily as a source region for reworked nannofossils and the role of rivers as their carrier. Eustatic sea-level fluctuations can be considered to be the main factor that influenced the abundance variations in sedimentary sequences of this area. The distribution of Florisphaera profunda can be explained in terms of topography (positive correlation) and mesoscale oceanographic circulation. In particular, its significant anti-correlation to the amount of chlorophyll-A deduced by satellite imagery validates the use of this species as a proxy for palaeoproductivity reconstructions. Finally, high abundance values of G. oceanica are confined to the westernmost part of the Sicily Channel, coinciding with a water mass salinity minimum. In particular, abundances of up to about 10% were observed in the westernmost part of the African Margin, suggesting the importance of the Atlantic Tunisian Current, whose activity is more pronounced in winter. The comparison of data of this species between 135 and 110 kyr BP, inside and outside the Channel, led us to deduce that the physical transport in almost unmodified waters of Atlantic origin might be the most important factor for its significant occurrence. [Copyright &y& Elsevier]

Abstract: This paper presents the results of a study based on data collected during the oceanographic cruise ANSIC 2001 carried out in the Ionian Sea during the explosive activity of Mount Etna in the summer of 2001. Anomalous low values of Y/Ho ratios in seawater suggest extensive scavenging processes on the surfaces of smectitic alteration products, with Y and Ho fractionation controlled by the differences in their electronic configurations and behaviour during solution/surface complexation equilibria. These processes can also be traced through the presence of significant tetrad effects recorded in the chondrite-normalised Rare Earth Elements and Yttrium (YREEs) patterns of suspended particulate matter. This suggests that the preferential Y scavenging from seawater is due to the formation of inner-sphere complexes with OH− groups on montmorillonite crystal surfaces. The preliminary results of kinetic experiments of YREE released from volcanic ash to coexisting seawater, and the related effects on Y/Ho ratios and Ce anomalies, are consistent with the fractionation of Light Rare Earth Elements (LREEs) with respect to Heavy Rare Earth Elements (HREEs) observed in dissolved phase. They suggest a behaviour of Y similar to that reported for LREEs, particularly for Ce and Pr. [Copyright &y& Elsevier]

Abstract: A geochemical survey of the northwestern part of the Thailand Gulf (Inner Gulf) was carried out in order to define concentrations and distribution patterns of selected heavy metals (V, Cr, Co, Ni, Cu, Zn, and U) in the coastal system and estuarine area of the Mae Klong river. The results indicate the presence of two different sources of heavy metals in the studied environment and allowed us to identify a lithogenic component that significantly influences the composition of coastal waters and suspended particulate matter (SPM). Comparison of the normalized heavy metals concentrations both in the studied samples and in those reported for the Sn–W ores present in the surrounding areas suggests an important anthropogenic contribution to the chemistry of the seafloor sediments. Vanadium and nickel enrichment factors (EF) calculated for coastal waters indicate that contamination by hydrocarbons discharge took place in the investigated area. [Copyright &y& Elsevier]

Abstract: Objective: To determinate the efficacy of “polytherapy”, a surgical technique that utilize all the components of the diamond concept (mesenchymal stem cells, bone morphogenetic proteins and scaffold) versus a “monotherapy”, a surgical technique that utilize only one component of the diamond conceptin the treatment of severe forearm non-unions. Methods: We studied a database of 52 patients with 52 forearm non-unions; we classified the patients with the NUSS SCORE and we divided the patients in two group according to the treatment received. So we distinguished a group of patients treated according to the principles of “monotherapy” (33 patients) and a group of patients treated according to the principles of “polytherapy” (19 patients). The minimum follow up was 12 months. Results: In the monotherapy group 21/33 non-unions (63.64%) went on to develop a radiographic and clinical healing within a period of 12 months, the calculated DASH SCORE showed a mean value of 55.15 points. In the polytherapy group 17/19 (89.47%) nonunions went on to develop clinical and radiographic healing within 12 months, and the average DASH score showed a mean value of 45.47 points. Conclusion: The polytherapy technique with the use of recombinant morphogenetic proteins, autologous MSCs and scaffold in the same surgical time appears to be an effective treatment for patients with severe forearm non-unions. [Copyright &y& Elsevier]