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Environmental (e)DNA metabarcoding holds great promise for biomonitoring and ecotoxicological applications. However, few studies have compared the performance of eDNA versus eRNA metabarcoding in assessing organismal response to marine pollution, in experimental conditions. Here, we performed a chromium (Cr)-spiked mesocosm experimental test on benthic foraminiferal community to investigate the effects on species diversity by analysing both eDNA and eRNA metabarcoding data across different Cr concentrations in the sediment. Foraminiferal diversity in the eRNA data showed a significant negative correlation with the Cr concentration in the sediment, while a positive response was observed in the eDNA data. The foraminiferal OTUs exhibited a higher turnover rate in eRNA than in the eDNA-derived community. Furthermore, in the eRNA samples, OTUs abundance was significantly affected by the Cr gradient in the sediment (Pseudo-R2 = 0.28, p = 0.05), while no significant trend was observed in the eDNA samples. The correlation between Cr concentration and foraminiferal diversity in eRNA datasets was stronger when the less abundant OTUs (

International audience; Gypsum makes up about one fifth of giant salt deposits formed by evaporation of seawater throughout Earth’s history. Although thermodynamic calculations and precipitation experiments predict that gypsum precipitates when the salinity of evaporating seawater attains about 110 g kg-1, gypsum deposits of the Mediterranean Salt Giant often bear the geochemical signature of precipitation from less saline water masses. Addressing this geochemical riddle is important because marine gypsum deposition and continental gypsum erosion affect the global carbon cycle. We investigated gypsum deposits formed in the marginal basins of the Mediterranean Sea during the Messinian Salinity Crisis (about 6 million years ago). These often bear low-salinity fluid inclusions and isotopically light crystallization water, confirming previous published reports that the Mediterranean Salt Giant harbors low-salinity gypsum deposits. A geochemical model constrained by fluid inclusion salinity and isotope (87Sr/86Sr, d34SSO4, d18OH2O, dDH2O) measurements excludes that Ca2+- and SO42--enriched continental runoff alone provides the trigger for gypsum precipitation at low salinity. We propose that, concurrent with the prevalent evaporative conditions and with Ca2+- and SO42--bearing runoff, the biogeochemical sulfur cycle is capable of producing a spatially-restricted and temporally- transient increase of Ca2+ and SO42- within benthic microbial mats, creating local chemical conditions conductive to gypsum precipitation. This hypothesis is supported by the presence of dense packages of fossils of colorless sulfur bacteria within gypsum in several Mediterranean marginal basins, together with independent geochemical and petrographic evidence for an active biogeochemical sulfur cycle in the same basins. Should this scenario be confirmed, it would expand the range of environments that promote marine gypsum deposition; it would also imply that an additional, biological coupling between the calcium, sulfur and carbon cycles exists.

OBJECTIVES: To assess the effect of the position of the SS on CI regarding the ability to perform posterior tympanotomy, round window visibility, and mastoid pneumatization. MATERIALS AND METHODS: This is a prospective study, including 65 adult patients with CI performed at our center during 2017. We used 3 methods to assess SS position using a computed tomography (CT) scan. Lee’s line passing through the tympanic segment of the facial nerve. Park’s line passing through the facial nerve and round window membrane. Our proposed method using a parallel line from the external auditory canal and passing through the facial nerve. Relation to mastoid pneumatization on CT and to intraoperative round window visibility were assessed in relation to intraoperative position of the SS. RESULTS: The method by Park et al. was statistically significant (p

In this paper, a complete three-dimensional (3D) RF model of the cyclotron coaxial resonator—including the coaxial sliding shorts, the “Liner” vacuum chamber, the coupler, the trimmer, and the high RF voltage “Dee” structures—has been developed. An eigenmode analysis was used to simulate the tuning of the resonator in the operating frequency range of 15–48 MHz obtained by two movable sliding shorts and a trimmer. A driven analysis has been performed in order to compute the |S11| parameter (or impedance matching) of the cavity excited by a movable coaxial power coupler. The numerical simulations have been performed using the different peculiarities of two commercial tools, COMSOL Multiphysics and CST microwave studio. Experimental validation of the developed model is presented. The evidence of an unwanted electric field component, orthogonal to the accelerating field, was discovered and a mitigation is also proposed. The impact of the proposed modification was evaluated by using a 3D beam dynamics code under development in the framework of the Superconducting Cyclotron upgrade ongoing at INFN-LNS.

Unmanned aerial vehicles (UAVs) are autonomous devices employed as data collectors in precision agriculture to support a large number of applications. These UAVs gather data from on-the-ground wireless sensor networks, especially in scenarios that lack any kind of fixed communication infrastructure or where the available infrastructure does not fit the application requirements. Sensors on the ground can store sensing data, and in scenarios that do not require a real-time observation and analysis of the data, like in smart farming, a drone can be used maybe once or two times each day to collect and report the data to a command-and-control center that use them directly, without any other infrastructure (cloud or edges). In this article, we study analytically how close the drone, that uses a LoRa radio, needs to fly over the sensors to collect data with a given quality of data collection. This can be used to properly spacing the sensors on the field at deployment time, to select among different type of drones, and to properly solve some tradeoff related to field size vs autonomy of the drones and the path used by the latter when collecting the data.

International audience; Unlike most Neogene basins of the Betic Cordillera where the Salinity Crisis is dated to the Messinian, a contradictory Tortonian dating was proposed for evaporites of the Lorca Basin. As a consequence, complex structural models have been proposed in the literature to explain this discrepancy in the timing of evaporites. In order to integrate the Lorca Basin into the geological context of the western Mediterranean domain during the Late Miocene, new sedimentological and stratigraphical studies coupled with new dating were performed, which allow us to propose a Messinian age for both diatomite-bearing deposits and evaporites of the Lorca Basin. These new ages challenge the idea of a Tortonian salinity crisis in the Lorca Basin. Three main events of base-level drop were evidenced during the Messinian. Each event is correlated with successive steps of basin restriction. Shallow salina evaporites were deposited after a base-level fall during the Messinian before a final base-level drop, which led to the entire exposure of the basin. This last exposure is interpreted as coeval with the deposition of first evaporites and halite in the deep Mediterranean basins. The reflooding which allowed the deposition of brackish deposits and a short-lived marine incursion occurred at the end of the Messinian. Base-level drops occurred during eustatic falls amplified by the gradual uplift of the Betic Cordillera. The exhumation of the Tercia ridge along the strike-slip Alhama de Murcia fault system during the Messinian probably favoured the gradual restriction of the basin. A discussion on correlations of main unconformities between several Neogene basins of the Betics is proposed, suggesting a similar structural evolution at the regional scale.

Globorotalia truncatulinoides oscillations have been recorded from different marine sediment cores collected in the central and western Mediterranean Sea. The abundances of this species over the last 500 yrs. demonstrates its potential value as bio-indicator of particular oceanographic condition during the Maunder Minimum (MM) event of the Little Ice Age (LIA). The comparison between the G. truncatulinoides abundance patterns of the Balearic Basin, central and south Tyrrhenian Sea and central and eastern Sicily Channel allows to highlight a similar response of this species during the MM event in the central-western Mediterranean Sea. The ecological meanings of this species and its peculiar high abundance percentages in the total assemblages suggest the development of enhanced vertical mixing conditions during MM winter season with a strong advection of nutrients from the nutrient-rich deeper layers and enhances the productivity levels in the mixed layer. The intensified vertical mixing could be linked to persistence of an atmospheric blocking event recorded by several authors during the MM.

The return to normal marine conditions in the Mediterranean Sea after the end of the Messinian Salinity Crisis (MSC), that led to the deposition of thick evaporitic succession followed by settlement of brackish to freshwater conditions of the “Lago-Mare”, is still subject to extensive debate between two opposite scenarios. One scenario implies an abrupt reflooding through the Gibraltar gateway of the Mediterranean Sea previously disconnected from the world ocean and partly desiccated. The second scenario postulates that the Mediterranean Sea kept a high-water level throughout the Messinian Salinity Crisis and was connected continuously to the Atlantic Ocean and to the Paratethys. The stratigraphic record of the classical Cuevas del Almanzora section (Vera Basin) is of a crucial importance as the Vera Basin is located on the eastern margin of the Alboran Sea close to the Gibraltar gateway where Atlantic waters reflooded the Mediterranean Sea after the MSC. The present new study completes previous investigations ( Pierre et al., 2006 ) and is mostly focused on detailed sedimentological observations, analysis of ostracod and foraminifer assemblages and on stable isotopes study of three species of planktonic foraminifers (Globigerina bulloides, Globigerinoides obliquus s.l. and Sphaeroidinellopsis spp.) from the lower Pliocene deposits. Biostratigraphical correlations with the reference deep-sea section from ODP Site 975 (Balearic Basin) and the onshore succession of Eraclea Minoa (Sicily) provide an accurate chronostratigraphy and paleoclimatic reconstruction during the Zanclean. During the late Messinian, the Vera Basin was characterized by very unstable lacustrine to brackish environments with significant water depth variations and the deposits display evidences of subaerial exposure. The ostracod content is dominated by Loxocorniculina djafarovi and Cyprideis gr. agrigentina associated to reworked planktonic foraminifera from older sediments. The Messinian/Zanclean contact is well marked by a clear erosional surface that grades laterally into a megabreccia with reworked gypsum blocks and to the large incision of the Palomares canyon in the offshore domain. The marine reflooding occurred abruptly with a sea level rise by more than 250 m, an important value for a marginal basin. In this western part of the Mediterranean Sea, the marine invasion began with the onset of the lowermost biozone MPl 1 at the base of the Zanclean. The fluctuations of the planktonic foraminifer assemblages and of their stable isotopes allowed to identify five lithological cycles forced by Milankovitch’ precession periodicity, as well as paleoclimatic variations through the lower part of the Zanclean. Thus, these new data allow us to reaffirm that the Messinian/Zanclean boundary corresponds to a major change, characterized by an “instantaneous” restoration of marine conditions at the onset of the Pliocene, related to the abrupt re-flooding of the Mediterranean Sea from the Atlantic Ocean.

The Internet of Things (IoT) paradigm poses a great variety of application domains where million of devices work uninterruptedly to improve some aspect of our lives. To support the continuous execution of the applications working on the devices, energy harvesting systems enable to extract the energy found naturally in the environment (for instance from the sun or from the wind) and convert it into energy able to either sustain the device’s operation and recharge its batteries which, in conjunction with an appropriate scheduling strategy, led to the device to an electrically sustainable state (i.e. an energy-neutral state). Most of the works found in literature oriented to achieve energy neutrality are however evaluated by means of simulation which means that, in spite of precisely modeling hardware features and energy productions, lack of the realism that we find in a real deployment. A minor part of the works are based on a real deployment but do not share the collected data that permit to replicate the analysis. With this purpose in mind, in this article we describe a testbed designed for outdoor monitoring purposes in the IoT context, equipped with several sensors for weather conditions monitoring and with a solar panel to provide application lifetimes potentially infinite. The testbed was deployed on the roof of a building and it executed uninterruptedly an application able to generate a dataset with the collected information over a period of more than two months. This dataset has been online published to be used for different researching purposes, as for instance, prediction models of the energy production.

To make sustainable large IoT deployments in smart cities, a promising approach is to develop a new generation of solar energy harvesting IoT devices based on the concept of energy neutrality. Key to this concept are the models for the forecast of energy production, which provide input to the energy-neutral schedulers governing the activities of the IoT devices. The development of such models however need to be validated against real-world conditions. To this purpose we propose a testbed aimed at the collection of real-world dataset about the energy parameters of energy harvesting IoT devices, and, on the base of such a dataset, we perform a comparative assessment of state of the art and novel energy production forecast models.

This study updates the current distribution, range expansion and establishment status of the non-indigenous species Amphistegina lobifera Larsen, 1976 and other foraminifera that are cryptogenic in the Sicily Channel. Prior to this study, amphisteginids were reported from the Levantine Basin, the Central Mediterranean (Tunisia, Malta, Pelagian islands) and the southern Adriatic Sea. Here, we provide new records documenting a north-western expansion in the Central Mediterranean. In summer-autumn 2017 and spring-summer 2018, we collected algae and sediment samples from shallow coastal habitats along the shores of the Maltese archipelago, southern and north-western Sicily, Pantelleria and the Aegadian islands. Analysis of the foraminiferal assemblages showed that A. lobifera is effectively established around Malta and in southern/south-eastern Sicily, and has reached the oceanographic boundary between the Central and Western Mediterranean. Our results also show that the thermotolerant A. lobifera is at an advanced stage of invasion in the Sicily Channel, probably favoured by a recent rise in Mediterranean sea surface temperatures. New species distribution models are provided for the years 2040–2050 and 2090–2100, indicating that the predicted warming trend will facilitate north-westward migration of Mediterranean amphisteginids along the coast of northern Africa into the Alboran Sea, and deep into the Adriatic Sea.

Globigerinoides ruber is the dominant taxon in the North Atlantic Subtropical Gyre, nowadays limited to the north by the Azores Current. It is highly sensitive to recent and late Pleistocene Azores Front Current System variability. In this study, we analyse the distribution of five individual morphotypes of the G. ruber – G. elongatus plexus (G. ruber s.s., G. ruber cyclostoma type, G. elongatus, G. elongatus cf.1, G. elongatus pyramidical type) and G. ruber kummerform gr. in a core (ATA13-OF-KT1) collected southwest of the Azores islands and located in a strategical position near the present-day boundary of the Subtropical Gyre/Azores Front Current System (STG/AFCS). Micropaleontological and stable isotope analyses can provide new insights on the ecological preferences of the G. ruber chromotypes and some selected morphotypes (especially the less studied G. ruber cyclostoma type). Their distribution pattern shows cyclic oscillations linked to climatic variability at orbital and millennial scales. G. elongatus clearly dominated the G. ruber - G. elongatus assemblage during the interglacials, while G. ruber cyclostoma type reached their maxima abundances during glacial periods. Furthermore, changes in the relative abundance of warm (G. elongatus) and cool water (G. ruber cyclostoma type) morphotypes represent a powerful tool to track the position occupied by the Subtropical Gyre/Azores Current (STG/AC) boundary during the last 74.7 kyr.

Scheduling tasks appropriately in an IoT device powered by multiple energy-harvesting sources is a challenging problem. In this paper, we model this problem, and we present a scheduling algorithm that optimally sets the overall node power consumption based on the utility, and on the energy required by tasks. The algorithm schedules high-level tasks, it uses the weather forecast informations available at the beginning of each scheduling period (typically a day), and the level of the battery, to define an optimal schedule. The main goal is to find a schedule that is energy neutral on average, over a period longer than the single scheduling window, for example a week. We test our scheduler on a simulated platform with the same specs of an Arduino node, equipped with a small (portable) solar panel, and attached to a small wind turbine. We see from the simulations that the scheduler performs as expected and that the utility of the scheduling improves as the error between the expected forecast and the real harvested energy is reduced.

Mercury (Hg) is a highly toxic element for living organisms and is known to bioaccumulate and biomagnify. Here, we analyze the response of benthic foraminifera communities cultured in mesocosm and exposed to different concentrations of Hg. Standard morphological analyses and environmental DNA metabarcoding show evidence that Hg pollution has detrimental effects on benthic foraminifera. The molecular analysis provides a more complete view of foraminiferal communities including the soft-walled single-chambered monothalamiids and small-sized hard-shelled rotaliids and textulariids than the morphological one. Among these taxa that are typically overlooked in morphological studies we found potential bioindicators of Hg pollution. The mesocosm approach proves to be an effective method to study benthic foraminiferal responses to various types and concentrations of pollutants over time. This study further supports foraminiferal metabarcoding as a complementary and/or alternative method to standard biomonitoring program based on the morphological identification of species communities.

This study presents the results of an integrated stratigraphic analysis conducted on a marine gravity core (MSK-12 C4) recovered from the outer continental shelf (82 mwater depth) of western Calabria, ~2.6 km, NE of Capo Vaticano (Eastern Tyrrhenian margin). The gravity core MSK-12 C4 recovered a stratigraphic succession of 4.18 m beneath the seafloor representing the last ~11.1 ka. Sedimentological analysis, micropaleontological quantitative analysis on benthic foraminiferal assemblages, tephrostratigraphy, sequence stratigraphic analysis of high resolution reflection seismic data recorded in the core site area and AMS 14C absolute age determinations allowed reconstructing the marine record of the eastern Tyrrhenian margin. Major results of the research work include the progressive sea level rise that controlled the evolution of the western shelf of Calabria during the Holocene and the identification of significant paleoenvironmental and paleoclimatic events. First, a short-lived period (10.6e9.4 ka BP) characterized by a significant increase river discharge seems to reflect a major rainfall during the earliest onset of the Holocene climatic warming. Second, the occurrence of a stratigraphic gap from 8.4 to 5 ka BP possibly the result of non-deposition and/or erosion due to bottom currents. The latter should follow from a major reorganization of the deep water currents system that accompanied the climax of the Holocene warming (Holocene climatic optimum). Third, the micropaleontological evidence of the Little Ice Age (LIA) that, on the basis of the chronology adopted in this study, can be constrained between ~1600 AD and ~1850 AD.[object Object]

Background Safe and effective insulin therapy for diabetes mellitus requires initial dose titration and regular adjustments based on blood glucose (BG) monitoring. Our objective was to explore the use of BG measurement in phase-III clinical studies of insulin analogs. These studies provide safety and efficacy information for regulatory authorities and are the basis for insulin analog regulatory approval. Methods A systematic review of phase-III studies of rapid-acting insulin analogs (insulin lispro, insulin aspart and insulin glulisine) and pre-mixed insulin analogs (biphasic insulin aspart and insulin lispro mix) was conducted. Studies were identified using manufacturers’ databases. Search for reports was performed in Medline and registry of clinical trials (clinicaltrials.gov). The European Medicines Agency was contacted to provide Clinical Study Reports. Results Forty-five studies were included. Regular BG measurements were reported in 100 % of the studies and were performed by either self-monitoring of blood glucose (SMBG) alone in 84 %, laboratory alone in 7 %, and both SMBG and laboratory in 9 % of studies. In total, 93 % of the studies reported SMBG. Most studies (91 %) reported insulin therapy adjustments based on BG measurements. Conclusions The findings suggest that BG monitoring and specifically SMBG are co-dependent technologies with insulin analogs. BG measurement is used in most phase-III registration studies for establishing safe and efficacious insulin administration and is recommended in the insulin labels. The indispensable role of SMBG in treatment of insulin-dependent patients should receive attention from health care payers to assess and reimburse SMBG along with insulin to avoid adverse events from inappropriate insulin administration and associated costs.

Manzi et al. (in press) took the opportunity offered by our paper to repeat again all the set of ideas supporting an interpretative model of the Messinian Salinity Crisis (MSC), a model they assert to be valid for the whole Mediterranean basin. What emerges from reading this long comment may be summarized in one criticism of our article: we have not systematically applied their interpretative model to our data! The aim of our paper was not to promote their ideas, but to submit the results of more than 20 years of field studies and petrographical and geochemical analyses on Sicilian and Calabrian sequences of the Messinian “Calcare di Base”. It is out of our purpose to enumerate again in this reply the data and interpretations we have developed in our paper, which disagree with their model and rule out most of their propositions. Thus, we will not reply in detail to this repetitive stream of ideas supporting their model. But we want to respond to some general and unfair comments, which are often far away from objectivity, and rectify some inaccurate assertions about the description of some sections.

Underwater communications through acoustic modems rise several networking challenges for the Underwater Acoustic Sensor Networks (UASN). In particular, opportunistic routing is a novel but promising technique that can remarkably increase the reliability of the UASN, but its use in this context requires studies on the nature of mobility in UASN. Our goal is to study a real-world mobility dataset obtained from the Argo project. In particular, we observe the mobility of 51 free-drifting floats deployed on the Mediterranean Sea for approximately one year and we analyze some important properties of the underwater network we built. Specifically, we analyze the contact-time, inter- contact time as well density and network degree while varying the connectivity degree of the whole dataset. We then consider three known routing algorithms, namely Epidemic, PROPHET and Direct Delivery, with the goal of measuring their performance in real conditions for USAN. We finally discuss the opportunities arising from the adoption of opportunistic routing in UASN showing that, even in a very sparse and strongly disconnected network, it is still possible to build a limited but working networking framework.

The uptake of two heavy metals (chromium and lead) in sediments in experimental mesocosms under exposure to different metal concentrations was evaluated by monitoring their concentrations over time both in seawater and in sediment. Two separate experiments under laboratory-controlled conditions were carried out for the two metals. Sediments were collected from a protected natural area characterized by low anthropic influence and were placed in mesocosms that were housed in aquaria each with seawater at a different metal concentration. At pre-established time intervals, seawater and sediment samples were collected from each mesocosm for chemical analyses. Quantification of chromium and lead concentration in seawater and sediment samples was carried out by atomic absorption spectrometer with graphite furnace. Low doses of chromium and lead (

Mobile Social Networks represent a convergence between mobile communications and service-oriented paradigms, which are supported by the large availability and heterogeneity of resources and services offered by recent mobile devices. In particular, the service-oriented nature of MSN is in the capability of sharing resources and services among devices that lie in proximity and that opportunis- tically interact. Service discovery is thus of primary importance to sustain the most intimate mechanisms of MSN. Despite of their centrality, studies on service discovery in MSN are still in their youth. We contribute to frame the results achieved so far and to identify some possible perspectives of the research in this field, by giving a transversal review of the scientific outcomes in the different steps of service discovery, namely advertisement, query, selection and access.

The SPES project is the new Radioactive Ion Beam facility under construction at the Laboratori Nazionali of Legnaro, Italy. In this framework, the realization of a new RFQ Beam Cooler (RFQBC) is in progress. This device allows to improve the quality of the low energy ion beams produced by the ISOL technique, granting a reduction of transverse emittance and energy spread. The RFQBC is an electromagnetic apparatus operating with oscillating electric fields needed to confine the very low energy (eV) ions (Q=1+) which lose both the longitudinal and transversal momentum by making collisions with lighter atoms of the so called buffer gas (He). This process provides the reduction of the transversal emittance up to 10 times of the initial value and it keeps the energy dispersion within 2-3 eV. The electromagnetic design of the RFQ section and the electrostatic layout of the injection and extraction regions have been done. The beam dynamics study is going on by means of dedicated codes which allow to take into account the interaction of the ions with the buffer gas needed to cool the beams. The RF group of LNS Catania is involved in the design of the RF system (500W) providing the oscillating high voltage (up to 3 kV) at frequency which varies in the range of 1-30 MHz. The preliminary design of the device started in 2011 in the framework of REGATA experiment of the 5 th scientific committee of INFN and it is carrying on within the COOLBEAM experiment.

The response of benthic foraminiferal assemblages to trace element pollution in the marine sediments of the Gulf of Milazzo (north-eastern Sicily) was investigated. Since the 1960s, this coastal area has been a preferred site for the development of two small marinas and a commercial harbour as well as for heavy industry. Forty samples collected in the uppermost 3-4 cm of an undisturbed layer of sediment in the littoral environment were used for this benthic foraminiferal analysis. The enrichment factors (EFs) of selected trace elements (As, Co, Cr, Cu, Mn, Ni, Pb and Zn) were also calculated. Changes both in benthic foraminiferal assemblages and in some trace elements concentrations have provided evidence that the gulf's littoral zone can be subdivided into three sectors characterised by environmental changes in the marine ecosystem. In the sector unpolluted, close to the Milazzo Cape, foraminiferal assemblages exhibit high values of species richness and foraminiferal density while trace element concentrations and their EFs are very low. Here, the highest densities of Miliolids and epiphytic species are present. On the contrary, in the sector polluted, from the marinas to the crude oil refinery, foraminiferal density and species diversity are low, and assemblages are dominated, albeit with very low densities, by species that tolerate stressed environmental conditions, such as LOFAs, agglutinants and Ammonia spp. Here, the highest trace elements concentrations of Pb, Zn and Cu and related EFs were detected. Eastwards, in the sector moderately polluted, foraminiferal populations are quite poor. They are characterised by low values of species richness and foraminiferal densities, nevertheless trace element concentrations become lower than in the other sectors and their EFs are often below 1. Deformed foraminifera, with percentages up to 7.14 %, were found in all three of the sectors. Differences in benthic foraminiferal assemblages, coupled with results from statistical analysis, indicate that anthropogenic trace element pollution could be considered as one of the most important causes of the modifications of foraminiferal assemblages in the study area.

The present study deals with the reconstruction of the environmental evolution of a Trapani saltmarsh (southwestern Sicily, Italy) by combining different analytical approaches such as metal content evaluation, low-field nuclear magnetic resonance (NMR) relaxometry, and benthic foraminifera identification. A 41 cm core was collected in the sediments of a Trapani saltmarsh (southwestern Sicily, Italy) at a water depth of about 50 cm. Different time intervals were recognized, each characterized by peculiar features that testify different environmental conditions. In particular, the bottom layers of the sediment core (41–28 cm) comprised the lowest amount of mud fraction, only some selected metals, and the lowest foraminiferal density. Here, co-occurrence of abundant microcrystals of gypsum and Ammonia tepida is indicative of hyper-saline conditions. In the sediments from 28 to 6 cm, mud fraction and number of metal elements resulted higher due to the increase of the anthropogenic pressure. The sediments in the last time interval, corresponding to the environmental recovery of the saltmarsh, showed an increase of foraminiferal density, a decrease of the mud fraction, and a trend in the metal concentration attributable to the protection policy applied since 1990. NMR relaxometry parameters highlighted the changes of sediment chemical–physical heterogeneity going from the bottom to the top of the core. These heterogeneities have been related to the different intervals recognized as aforementioned. The present study highlights how the anthropogenic pressure modifies the environmental conditions of a transitional ecosystem like saltmarshes.

To examine the suitability of benthic foraminifera and their test deformations as bioindicators of pollution in coastal marine environments, we studied foraminifera and metal concentrations in 72 marine sediment samples, collected from the inner shelf along the Sicilian coast (Gulfs of Palermo and Termini) and on the south-eastern coast of Lampedusa Island. These areas are characterised by different environmental conditions. On the basis of pollution sources and foraminiferal assemblages, we recognised different zones in the Gulf of Palermo. The most polluted zones showed high metal concentrations, and low diversity of benthic foraminifera with species typical of stressed environments. By contrast, the lowest polluted zones showed a high population density and the highest percentages of epiphytes. Epiphytes were abundant where a Posidonia oceanica meadow was present and decreased in the most polluted zones. Sediments of the Gulf of Termini and Lampedusa exhibited high percentages of benthic foraminifera typical of well-oxygenated waters and low concentrations of metals, with the exception of sites located near sewage outfalls and harbour areas. Furthermore, even though deformed tests are commonly known in natural stressed environmental conditions, this study shows that in the most polluted zones, benthic foraminifera were characterised by the highest percentages of deformed individuals.

International audience; How the Messinian Salinity Crisis (MSC) ended is still a matter of intense debate. The Terminal Carbonate Complex (TCC) is a late Messinian carbonate platform system that recorded western Mediterranean hydrological changes from the final stages of evaporite deposition till the advent of Lago-Mare fresh- to brackish water conditions at the very end of Messinian times. A multidisciplinary study has been carried out in three localities in south-eastern Spain to reconstruct the history of TCC platforms and elucidate their significance in the MSC. Overall, this study provides evidence that the TCC formed following a regional 4th order water level rise and fall concomitant with an opening-restriction trend. It can be subdivided into four 5th order depositional sequences (DS1 to DS4) recording two phases: (1) from DS1 to DS3, a tide-dominated ooidic to oobioclastic system with stenohaline faunas developed as a result of a 70 m water level rise. During this period, the TCC developed in a shallow sea with close to normal marine salinity; (2) in depositional sequence 4, a microbialite-dominated platform system developed. This is indicative of a significant environmental change and is attributed to a 30 to 40 m water level fall in the basins under study. These restricted conditions were coeval with intense evaporite deformation and brine recycling. The synsedimentary deformation of evaporites had a major impact on platform architecture and carbonate production, affecting the Messinian series throughout south-eastern Spain at the end of the TCC history. At that time, the TCC developed in a lake with fluctuating, brackish- to hypersaline water. These findings suggest a temporary restoration of marine conditions in the western Mediterranean marginal basins due to Atlantic water influxes prompted by a global sea level rise around 5.6 Ma. Whether marine conditions extended to the entire western Mediterranean still needs to be investigated.

Microbially formed authigenic carbonates accompanied by native sulphur are present in the ‘Calcare Solfifero’ below a thick succession of gypsum deposited during the Messinian salinity crisis in Sicily. We sampled these carbonates and associated sulphur in five former sulphur mines to subject them to a detailed petrographic and geochemical study in order to explore their different modes of formation. Native sulphur formed in conjunction with microbial sulphate reduction, which is reflected in its depletion in 34S (δ34S values as low as − 2‰ vs. V-CDT) and an enrichment of 34S in the residual sulphate (δ34S values as high as + 61‰). The oxidation of organic matter by sulphate reduction increased alkalinity, inducing precipitation of secondary carbonate minerals. A set of authigenic limestones lacking sulphate minerals, but characterized by pseudomorphs after gypsum and high δ18O values (as high as + 9‰ vs. V-PDB) reflects syngenetic mineral formation within evaporitic settings. Low δ13C values (as low as − 52‰ vs. V-PDB) reveal that these carbonate phases were formed by microbial sulphate reduction coupled to the oxidation of biogenic methane. Another set of authigenic carbonates that replaced sulphate minerals is typified by low δ18O values (as low as − 4‰). These carbonates formed epigenetically during later diagenesis following compaction. Dissolution of gypsum or anhydrite by meteoric waters delivered the sulphate for microbial sulphate reduction. Low carbon isotope values of these carbonates (− 29 to − 5‰) indicate that carbonate was derived from the oxidation of crude oil and possibly minor methane, partly involving different degrees of admixture of dissolved carbonate from other sources. Although the studied rocks with their vast amounts of secondary carbonate minerals and sulphur seem to indicate a similar genesis at first glance – having formed by biogeochemical transformations of sulphate and hydrocarbons – this study reveals that these processes can occur at different times in variable geological environments.

23 pages; International audience; During the Miocene, Mediterranean shallow-water carbonates were rich in scleractinian corals, which thrive in various depositional settings. A Tortonian–Messinian bioherm belt developing in a heterozoan-dominated ramp was investigated along a 1.2 km continuous transect located in the Cabo de Gata region. The interval studied displays four depositional environments from mid-to-inner ramp, dominated by swell waves and storm energy, deposited as a single, large-scale depositional sequence during a 3rd to 4th order transgressive–regressive cycle. The bioherms grew in three phases, and were essentially composed of inplace primary frameworks. Three coral genera were the main framebuilders (Porites, Tarbellastrea and rare Siderastrea), associated with melobesioid and mastophoroid red algae and bryozoans as secondary framebuilders. The corals display five morphotypes, from a fast-growing branched type to slow-growing domal to plate morphologies, with an uncommon form of mesh Porites as the dominant morphotype. Changes in coral morphotype and composition of micro-encrusters communities reveal changes in hydrodynamics, detrital influx and perhaps nutrient levels. Bioherms architecture was driven by sea level, palaeotopography and erosion. The coral framework was affected during its development by erosion surfaces metres to tens of metres deep and hundreds of metres wide. Unexpectedly, these surfaces are better developed on the inner edges of the bioherms. This could indicate the circulation of strong bottom currents between the volcanic palaeohighs and the synoptic relief created by the buildups. Finally, a major sub-aerial erosional episode associated with increasing detrital influxes, ended bioherm development, thus allowing the colonization of the dead coral substratum by red algae.

The distributed gradient protocol is a common building block to perform several tasks in a wireless sensor network. The gradient calculates the minimum hop-distances between each sensor and a specified set of anchor sensors. This calculation is performed using a distributed greedy forwarding of messages in the network. Several virtual localization protocols use gradients to compute the virtual coordinates of the sensors. The quality of these coordinate systems depends on the relation between the value of the gradient and the real geographic distances between sensors. In this paper a formal proof of such relation is provided in the case of dense sensor networks with homogeneous sensor communication range r. The minimum-hop distances between a sensor and an achor is bounded to be in a range defined by two geographic distances. The size of this range decreases with increasing density of the network and it is equal to the maximum resolution (the communication range r) when the density is high enough.

Within a more general study on marine sediments in the Gulf of Palermo (Sicily, Italy), the 210Pbex dating method (using a model with constant sedimentation rate) has been applied to one sediment core. The main goal of the research was to study the Pb pollution chronology. Dating of the core has allowed evaluating the time evolution of the gulf lead concentrations. Specific activities of 137Cs have also been measured in the sediment core sections as an independent confirmation of the chronology derived by the 210Pbex method. The time scale has then been used to correlate lead concentrations in core sections to estimated lead emissions in air due to gasoline combustion. A good correlation between the two data series has been obtained.

We analyze the spatial distributions of two groups of benthic foraminifera (Adelosina spp. + Quinqueloculina spp. and Elphidium spp.), along Sicilian coast, and their correlation with six different heavy metals, responsible for the pollution. Samples were collected inside the Gulf of Palermo, which has a high level of pollution due to heavy metals, and along the coast of Lampedusa island (Sicily Channel, Southern Mediterranean), which is characterized by unpolluted sea waters. Because of the environmental pollution we find: (i) an anticorrelated spatial behaviour between the two groups of benthic foraminifera analyzed; (ii) an anticorrelated (correlated) spatial behaviour between the first (second) group of benthic foraminifera with metal concentrations; (iii) an almost uncorrelated spatial behaviour between low concentrations of metals and the first group of foraminifera in clean sea water sites. We introduce a two-species model based on the generalized Lotka-Volterra equations in the presence of a multiplicative noise, which models the interaction between species and environmental pollution due to the presence in top-soft sediments of heavy metals. The interaction coefficients between the two species are kept constant with values in the coexistence regime. Using proper values for the initial conditions and the model parameters, we find for the two species a theoretical spatial distribution behaviour in a good agreement with the data obtained from the 63 sites analyzed in our study., 28 pages, 8 figures, 5 tables