Variability of water mass properties in the Strait of Sicily in summer period of 1998–2013

The Strait of Sicily plays a crucial role in determining the water-mass exchanges and related properties between the western and eastern Mediterranean. Hydrographic measurements carried out from 1998 to 2013 allowed the identification of the main water masses present in the Strait of Sicily: a surface layer composed of Atlantic water (AW) flowing eastward, intermediate and deep layers mainly composed of Levantine intermediate water (LIW), and transitional eastern Mediterranean deep water (tEMDW) flowing in the opposite direction. Furthermore, for the first time, the signature of intermittent presence of western intermediate water (WIW) is also highlighted in the northwestern part of the study area (12.235◦ E, 37.705◦ N). The excellent area coverage allowed to highlight the high horizontal and vertical inter-annual variability affecting the study area and also to recognize the permanent character of the main mesoscale phenomena present in the surface water layer. Moreover, strong temperature-salinity correlations in the intermediate layer, for specific time intervals, seem to be linked to the reversal of surface circulation in the central Ionian Sea. The analysis of CTD data in deeper water layer indicates the presence of a large volume of tEMDW in the Strait of Sicily during the summers of 2006 and 2009.peer-reviewe

La sostenibilità delle destinazioni turistiche: la misurazione per indicatori

Tourism often has had (and has) detrimental outcomes on destinations but the need and the rele-vance of a sustainable development of tourism was only recently recognised. Sustainable tour-ism is a quite recent concept, derived by the notion of sustainable development; it is usually re-lated to environmental issues and particularly to natural resources waste. Wider definitions are now emerging in the scientific community including, usually, social and economic dimensions together with the environmental one. Although, the intrinsic multidimensional nature of sustain-ability and the high number of stakeholders to be involved in its evaluation (e.g. policy makers, administrators, local residents, tourists, etc.) make quite difficult the definition and the meas-urement of this trait. This paper aims at a) analysing the complex relationship between tourism and environment (this last intended in its wider meaning); b) accounting for literature on the measurement of tourism sustainability of destinations through indicators; c) verifying the compliance of the reviewed composite indicators with the ‘European protocol’ for building of composite indicators

Persistent and Emerging Organic Pollutants in the Marine Coastal Environment of the Gulf of Milazzo (Southern Italy): Human Health Risk Assessment

The Gulf of Milazzo (north-eastern Sicily) has been recognized as Italian Site of National Interest (SNI; areas characterized by high level of contamination with potential effects on human health) in 2005 because of its high level of pollution. In this study we measured the concentration of polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides (OCPs), and polyBrominated diphenyl ether (PBDE) in seawater and sediments sampled from the Gulf of Milazzo in order to assess (i) the environmental status of contamination, and (ii) cancer and non-cancer human health risk potentially due to dermal absorption from contaminated seawater and/or ingestion of contaminated fish. Particularly, POPs content in pelagic and demersal fish of different size classes (small, medium, and large) were estimated, starting from the measured seawater and sediments concentrations, using the KABAM model. In particular, Monte Carlo simulation techniques were applied to address uncertainty in assessment of the risk and to provide quantitative estimates of probability of exposition. Ingestion of contaminated pelagic and demersal fish was the dominant pathway of exposition with high probability of significant cancer risk (Ingestion Cancer Risk >10–4) and significant non-cancer risk (Hazard Index >1). No human health risks emerged to be associated to dermal adsorption from contaminated seawater. Benzo(a)pyrene show the highest Ingestion Cancer Risk with respect to the other PAHs, while the highest Hazard Index for non-cancerogenic molecules was estimated for the PBDE47 congener

Morpho-sedimentary setting and evolution of Marettimo Valley (Egadi Islands, Sicily) during middle-late Quaternary: interaction between sea level changes and oceanographic circulation

We present morphological and stratigraphic results coming from surveys acquired in a NNW-SSE trending submarine depression (Marettimo Valley) located in the Egadi Islands (western Sicily offshore). In this area the seafloor is characterized by both depositional and erosional features generated under a variety of sedimentary processes. We identified two seismic facies units that are correlatable to: A) the progradation of shallow water (coastal to offshore) deposits during forced-regression sedimentary process, and B) contourite drifts emplaced by geostrophic currents through the Marettimo Valley. This unusual association of very shallow water contourites and shelf margin deposits originates, during middle-late Pleistocene glacio-eustatic cycles, from enhanced sedimentary dynamics establishing mutual interaction between progradational growth of the margin and bottom current depositio

Distribution of rare earth elements in marine sediments from the Strait of Sicily (western Mediterranean Sea): Evidence of phosphogypsum waste contamination

Concentrations of rare earth elements (REE), Y, Th and Sc were recently determined in marine sediments collected using a box corer along two onshore\u2013offshore 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 163.4 lg g 1) associated to high Th concentrations (mean value 7.9 lg g 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\u2013Gd\u2013Eu 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

Unexpected Effects of K⁺ and Adenosine Triphosphate on the Thermal Stability of Na⁺,K⁺‑ATPase

Na⁺,K⁺-ATPase is an integral membrane protein which couples ATP hydrolysis to the transport of three Na⁺ out and two K⁺ into the cell. The aim of this work is to characterize the effect of K⁺, ATP, and Mg²⁺ (essential activator) on the Na⁺,K⁺-ATPase thermal stability. Under all conditions tested, thermal inactivation of the enzyme is concomitant with a structural change involving the ATP binding site and membrane-associated regions. Both ligands exert a clear stabilizing effect due to both enthalpic and entropic contributions. Competition experiments between ATP and K⁺ showed that, when ATP is present, the inactivation rate coefficient exhibits a biphasic dependence on K⁺ concentration. At low [K⁺], destabilization of the enzyme is observed, while stabilization occurred at larger cation concentrations. This is not expected for a simple competition between the enzyme and two ligands that individually protect the enzyme. A model that includes enzyme species with none, one, or two K⁺ and/or one molecule of ATP bound explains the experimental data. We concluded that, despite both ligands stabilizing the enzyme, the species with one K⁺ and one ATP simultaneously bound is unstable

Eustatic and oceanographic control on sedimentary evolution of middle-late Quaternary shelf margin-to-upper slope deposits on the Egadi Islands offshore (Italy)

During the past decades a number of sequence stratigraphy studies illustrated how, during Quaternary, interaction between sea level changes and sediment supply controlled the depositional evolution along continental margins, giving a cyclic signature to the sedimentary infilling. However, as both deposition and erosion are processes ultimately controlled by balance between environmental energy and sedimentary influx, also the oceanographic regime takes part in controlling the sedimentary growth along the continental margin. This is exactly what occurs on physiographic settings as islands offshore areas, where bottom currents can be very energetic. In the western Sicily offshore, southwards of Egadi Islands, the sea floor is characterized by depositional and erosional features formed under a variety of sedimentary processes and offers opportunity to investigate as sea level change and oceanographic regime combine each other to control depositional evolution. In this area, located along the clockwise flow of the Levantine Intermediate Water around the western Sicily margin, the sea floor morphology is very irregular as consequence of isolated reliefs and narrow submarine valleys, such as the Marettimo Valley which separates Favignana and Marettimo islands. We analysed and interpreted a grid of high-resolution (1 kJ Sparker) seismic reflection profiles integrated with multibeam bathy-morphologic data of selected areas; a 270 cm long gravity core has been also collected for sedimentology and biostratigraphy. The sedimentary succession accommodated along the eastern flank of the Marettimo Valley shows two different seismic units: unit A displays reflection-free seismic facies and thin, low- amplitude, inclined reflectors with downlap terminations onto the lower boundary, and erosional truncation at the upper boundary; these seismic facies are referable to oblique-tangential clinoforms and show a wedge-shaped external geometry. Unit B shows continuous, parallel, slightly concave reflectors and, towards the central sector of the Valley, continuous, sub-horizontal reflectors that form a deposit having a very broad low-mounded geometry; lateral transition in between concave and sub-horizontal reflectors is characterized by channelized erosional truncations. The two seismic units can be interpreted as the sedimentary response of different depositional processes: unit A accumulated by progradation of shallow-water deposits during eustatic forced-regression; unit B is referable to contourite drifts deposited by bottom currents through the Marettimo Valley. This unusual interbedding of very shallow water contouritic and shelf margin deposits derives from enhanced sedimentary dynamics during sea-level fall and lowstand stages when, as consequence of decreased water depth of the Marettimo Valley, bottom currents accelerated scouring channelized erosional surfaces; in the same time, deposition of forced regression across the shelf margin buried contourite drifts

Chloroquine/hydroxychloroquine use and suicide risk: Hypotheses for confluent etiopathogenetic mechanisms?

Chloroquine (CQ) and hydroxychloroquine (HCQ) are classical anti-malarial and anti-inflammatory treatments, which were used as first-line therapy at the beginning of the 2019 coro-navirus disease (COVID-19) pandemic. Besides the emerging data on their lack of efficacy against COVID-19 infection, such treatments have been associated with some severe health concerns, including those of neuropsychiatric nature, such as a possible increase in suicide risk. Here we report a case of a patient with no history of psychiatric illnesses, who abruptly developed depression with melancholic features, severe suicidal ideation (SI), and attempted suicide (SA) shortly after receiving HCQ for his COVID-19 infection. The case was followed by a mini-review of the heterogeneous scientific literature on the hypothetical association between neuropsychiatric symptoms, with a focus on SI and suicidal behavior (SB, including SA and death by suicide), when CQ and HCQ are used in COVID-19, rheumatologic diseases, and malaria settings. Considering the anti-inflammatory properties of CQ and HCQ and the implications for neuroinflammation in suicide pathogenesis, the possible increase in suicide risk caused by these medications appears paradoxical and suggests that other underlying pathological trajectories might account for this eventuality. In this regard, some of these latter mechanistic postulates were proposed. Certainly the role and contribution of psycho-social factors that a COVID-19 patient had to face can neither be minimized nor excluded in the attempt to understand his suffering until the development of SI/SB. However, while this case report represents a rare scenario in clinical practice and no consensus exists in the literature on this topic, a psychiatric screening for suicide risk in patients using of CQ and HCQ could be carefully considered