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Since the excavations at Franchthi Cave in the 1960s and 1970s, the possibility of finding a submerged Neolithic site in the Bay of Kiladha has been discussed. Initial research, based on marine geophysical survey and core sampling, brought contrasted results. Starting in 2012, new parts of the Bay were investigated, using different techniques and improved methods, such as geological-geophysical survey, further core sampling (including the finding of artefacts and anthropogenic indicators of a given date in the cores), shallow water ERT (with an adapted methodology), and underwater excavation. The combined evidence leads to a reconsideration of previous work, to the discovery of submerged structures directly off the cave, which might well be Neolithic walls, and points to the existence of two new submerged sites, one dating to the Neolithic, in the middle of the Bay, and the other to the Final Neolithic/Early Bronze Age I, at Lambayanna. The implications of these findings are discussed as well. [ABSTRACT FROM AUTHOR]

The Balkan Peninsula lies on a key geographical location between Africa and Eurasia. The southern part of the Balkan Peninsula, referred to as the Aegean region, was a passageway for faunal migrations throughout the Pleistocene. Recent advances in the Lower Palaeolithic archaeology of Greece and in the research of the submerged landscapes of the Aegean region prompt a reconsideration of the biogeographical role of this area in Middle Pleistocene hominin settlement and expansion. In this paper, we articulate and elaborate on a working hypothesis, namely that the Aegean region was not a barrier during the Middle Pleistocene but instead it offered attractive lands for occupation and viable pathways for dispersal. Several methodological challenges emerge associated with the dynamic nature of the Aegean context. We propose an interdisciplinary approach to address the challenges. Using available archaeological and palaeogeographical evidence within a GIS-based framework, we seek to explore the 'hominin factor' in relation to the changing Aegean landscapes and geographical affordances. Shifting away from the 'terrestrial Eurocentric' point of view in the discussion of the patterns of early colonisation of Europe and the dispersal routes followed by hominins, we propose a revised understanding of early European settlement and its eastern gateways. [ABSTRACT FROM AUTHOR]

The current trend for Magnetic Resonance Imaging points towards higher magnetic fields. Even though sensitivity and resolution are increased in stronger fields, T1 contrast is often reduced, and this represents a challenge for contrast agent design. Field-dependent measurements of relaxivity are thus important to characterize contrast agents. At present, the field-dependent curves of relaxivity are usually carried out in the field range of 0 T to 2 T, using fast field cycling relaxometers. Here, we employ a high-speed sample shuttling device to switch the magnetic fields experienced by the nuclei between virtually zero field, and the center of any commercial spectrometer. We apply this approach on rare-earth (mixed Gadolinium-Europium) vanadate nanoparticles, and obtain the dispersion curves from very low magnetic field up to 11.7 T. In contrast to the relaxivity profiles of Gd chelates, commonly used for clinical applications, which display a plateau and then a decrease for increasing magnetic fields, these nanoparticles provide maximum contrast enhancement for magnetic fields around 1-1.5 T. These field-dependent curves are fitted using the so-called Magnetic Particle (MP) model and the extracted parameters discussed as a function of particle size and composition. We finally comment on the new possibilities offered by this approach. [ABSTRACT FROM AUTHOR]

Franchthi Cave, bordering Kiladha Bay, in Greece, is a key archaeological site, due to its long occupation time, from ~ 40,000 to ~ 5000 year BP. To date, no clear evidence of Neolithic human dwellings in the cave was found, supporting the assumption that Neolithic people may have built a village where there is now Kiladha Bay. During the Neolithic period/Early Holocene, wide areas of the bay were indeed emerged above sea level. Bathymetric and seismic data identified a terrace incised by a valley in ~ 1 to 2 m sediment depth. Eight sediment cores, up to 6.3-m-long, were retrieved and analysed using petrophysical, sedimentological, geochemical, and chronostratigraphic methods. The longest core extends into the exposure surface, consisting of a layer of carbonate rubble in a finer matrix, representing weathering processes. Dated organic remains place this unit at ~ 8500 cal year BP. It is overlain by stiff silty mud representing an estuarine environment. This mud is capped by reduced sediments with roots marking an exposure surface. A shell-layer, dated to ~ 6300 cal year BP, overlies this terrestrial sequence, reflecting the marine transgression. This layer occurs at 10.8 mbsl, 7.7 m deeper than the global sea level at that time, suggesting tectonic subsidence in the area. It is overlain by finer-grained marine carbonate-rich sediments. The top of the core shows traces of eutrophication, pebbles and marine shells, all likely a result of modern anthropogenic processes. These results are interpreted in the context of human occupation: the exposed surface contains pottery sherds, one dating to the Early to Middle Neolithic period, indicating that Neolithic people were present in this dynamic landscape interacting with a migrating coastline. Even if the artefacts are isolated, future investigations of the submerged landscape off Franchthi Cave might lead to the discovery of a Neolithic village, which eventually became buried under marine sediments. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented is response to articles regarding human dispersal in late Pleistocene epoch in the 2012 issue.

To conduct an economic evaluation estimating the cost per live birth after controlled ovarian stimulation (COS) using Follitropin Alpha (Gonal-F), in the Greek National Health System setting. A secondary objective was to predict the live birth rateof the In Vitro Fertilization (IVF) procedure. A single arm, multi-center, prospective, non-interventional study was conducted on which economic, efficacy and safety data were collected by six of the largest IVF centers. The participants were 350 female patients. Three statistical methods were employed for the analysis of the study outcomes, namely (a) Generalized Linear Modeling for the estimation of the costs of IVF treatment, (b) multivariable logistic regression and (c) an Artificial Neural Network (ANN) model for live birth prediction. The mean total cost of IVF therapy per patient was estimated at €3728 (95% CI: €3679–€3780), while the total cost per live birth was €14,872 (95% CI: €12,441–€17,951). The live birth rate after 3 complete IVF cycles was estimated at 22.9%, while the percentage of those suffering from OHSS was limited at 0.57%. In logistic regression, the Ovarian Sensitivity Index (OSI) was a factor found to be positively associated with live birth (OR 7.39, 95% CI: 1.84–29.71). For the ANN, important predictors included number of gestational sacs and the duration of infertility. The present study constitutes the largest single-arm study based on real data in Greece to date. The cost of IVF treatment and the cost per live birth are not insignificant in this NHS setting. The live birth rate, cost per oocyte, and the cost per live birth are in line with literature. OSI was a main contributing factor to the accurate prediction of the live birth rate, while age and BMI were found to be negatively correlated. [ABSTRACT FROM AUTHOR]

The southern Red Sea is a key region for investigating the effect of climate forces on a semi-closed basin. Detailed micropaleontological (planktic foraminifera) and isotopic (δ18Ο, δ13C) analyses along with reconstructions of sea surface temperature and salinity on a sediment core from the Farasan banks revealed the imprints of sea level changes and the South Asian Monsoon on the area. Comparison with surrounding records provided insights on the Red Sea-Gulf of Aden (GoA)-Northwestern Arabian Sea (NWArS) water exchange pattern over the last 30 ka. During glacial sea-level lowstand, flow of water from the GoA prevented hypersalinity in the southern Red Sea. Deglacial sea level rise improved water mass exchange between the NWArS, GoA and the entire Red Sea, resulting in relatively similar surface water conditions during the early Holocene when sea-level rise slowed. Thus, sea level change is the major driver of Red Sea δ18O variability. Southwest Monsoon (SWM), which was dominant during the late glacial and Early-Middle Holocene, enhanced surface productivity in the southern Red Sea. Northeast Monsoon (NEM) dominated around Heinrich stadial 1, as indicated by a nearly aplanktonic zone that was probably caused by restricted GoA inflow and low productivity. [ABSTRACT FROM AUTHOR]

The MagellanPlus workshop "BlackGate" addressed fundamental questions concerning the dynamic evolution of the Mediterranean–Black Sea (MBS) gateway and its palaeoenvironmental consequences. This gateway drives the Miocene–Quaternary circulation patterns in the Black Sea and governs its present status as the world's largest example of marine anoxia. The exchange history of the MBS gateway is poorly constrained because continuous Pliocene–Quaternary deposits are not exposed on land adjacent to the Black Sea or northern Aegean. Gateway exchange is controlled by climatic (glacio-eustatic-driven sea-level fluctuations) and tectonic processes in the catchment as well as tectonic propagation of the North Anatolian Fault Zone (NAFZ) in the gateway area itself. Changes in connectivity trigger dramatic palaeoenvironmental and biotic turnovers in both the Black Sea and Mediterranean domains. Drilling a Messinian to Holocene transect across the MBS gateway will recover high-amplitude records of continent-scale hydrological changes during glacial–interglacial cycles and allow us to reconstruct marine and freshwater fluxes, biological turnover events, deep biospheric processes, subsurface gradients in primary sedimentary properties, patterns and processes controlling anoxia, chemical perturbations and carbon cycling, growth and propagation of the NAFZ, the timing of land bridges for Africa and/or Asia–Europe mammal migration, and the presence or absence of water exchange during the Messinian salinity crisis. During thorough discussions at the workshop, three key sites were selected for potential drilling using a mission-specific platform (MSP): one on the Turkish margin of the Black Sea (Arkhangelsky Ridge, 400 m b.s.f., metres below the seafloor), one on the southern margin of the Sea of Marmara (North İmrali Basin, 750 m b.s.f.), and one in the Aegean (North Aegean Trough, 650 m b.s.f.). All sites target Quaternary oxic–anoxic marl–sapropel cycles. Plans include recovery of Pliocene lacustrine sediments and mixed marine–brackish Miocene sediments from the Black Sea and the Aegean. MSP drilling is required because the JOIDES Resolution cannot pass under the Bosporus bridges. The wider goals are in line with the aims and scope of the International Ocean Discovery Program (IODP) "2050 Science Framework: Exploring Earth by Scientific Ocean Drilling" and relate specifically to the strategic objectives "Earth's climate system", "Tipping points in Earth's history", and "Natural hazards impacting society". [ABSTRACT FROM AUTHOR]

Abstract: The Gulf of Corinth is the second most active continental rift in the world and thus a much-studied natural laboratory for analyzing details of rift history. A new detailed offshore seismic survey combined with previously acquired data in its least studied part, the Lechaion Gulf, shed light on the tectono-sedimentary evolution of the eastern end of the Corinth rift. This study shows that: (i) the Lechaion Gulf is the submerged northern part of the onshore Corinth–Nemea basin, (ii) they are both bounded to the south by the north dipping Klenia and Kenchreai faults, which are considered at present inactive, (iii) both the Corinth–Nemea basin and the Lechaion Gulf were formed at around between 3.6 and 4Ma BP (middle to late Pliocene), at the same time with the Megara basin, and (iv) the Lechaion Gulf was submerged and took its present shape at around between 0.7 and 1.7Ma BP, at the same time with the Gulf of Corinth and the Alkyonides Gulf. Furthermore, sequence stratigraphy interpretation of seismic profiles from the Lechaion Gulf revealed: (i) a total post-alpine sediment thickness of almost 3km below the Lechaion Gulf, (ii) at least 400m of sediments accumulated during the last 245ka, corresponding to a mean sedimentation rate of 1m/ka for the last 245ka and 2.3m/ka for the Holocene, and (iii) differential vertical movement, in the order of 4.5km, between the bedrock under the Lechaion Gulf and the adjacent mountains yields an accumulative average slip rate of 0.9m/ka or less, over the last 4Ma. Therefore, for estimating more accurately the slip rates, the uplift rates, the extensional rates and the earthquake recurrence interval over the eastern end of the Corinth rift, the presently mentioned tectono-sedimentary evolution of the Lechaion Gulf must be taken into consideration. [Copyright &y& Elsevier]

Abstract: Mapping (or plotting) the magnetic field has a critical importance for the achievement of the homogeneous magnetic field necessary to standard MR experiments. A powerful tool for this purpose is the Spherical Harmonic Expansion (SHE), which provides a simple way to describe the spatial variations of a field in free space. Well-controlled non-zero spatial variations of the field are critical to MRI. The resolution of the image is directly related to the strength of the gradient used to encode space. As a result, it is desirable to have strong variations of the field. In that case, the SHE cannot be used as is, because the field modulus variations are affected by the variations of all components of the field. In this paper, we propose a method based on the SHE to characterize such variations, theoretically and experimentally, in the limit of an axisymmetric magnetic field. Practical applications of this method are proposed through the examples of single-sided magnet design and characterization, along with Stray-Field Imaging (STRAFI). [Copyright &y& Elsevier]

The analysis of satellite-based Synthetic Aperture Radar Sentinel-1 data reveals the presence of an oil seepage system composed of 33 recurrent oil seeps sites in the Aegean Sea. The temporal analysis of this system shows that most oil seeps are detected during the summer period, probably due to better detection conditions during this period. The estimations of expulsion frequency computed using the summer period show that the frequency is highly variable from one seep to another with occurrence rates that reach 40% for the most active sites. Oil seeps gather among two main provinces. First, in the Limnos and Saros pull-apart basins where oil seeps are aligned along the North Anatolian Fault (NAF), which suggest that oil seep locations are mostly driven by the fault network. In the Limnos basin, detected oil seeps also coincide with the location of a gravity-driven sedimentary destabilisation complex that developed under the influence of the Limnos pull-apart basin subsidence and the transtensive strain of the NAF. Finally, oil seeps detected in the proximity of the Skyros-Edremit region seems to follow a different control considering that oil seeps appear disconnected from the main fault in the area (Skyros-Edremit). • Satellite imagery was used to monitor of oil seeps systems in the Aegean Sea • A total of 3300 slicks are expelled from 32 recurrent oil seeps sites. • Oil seeps occurs concomitantly with sediment destabilisation and tectonic processes. • The North Anatolian Faults is the main triggering seepage factor. • Oil seepages are intermittent and better detected during the summer periods. [ABSTRACT FROM AUTHOR]

Sediment transport processes from the slopes to the deep basins were studied in the southern Cretan margin (Eastern Mediterranean) by means of swath bathymetry, seismic reflection (airgun) profiling, and gravity coring. Mud/silt turbidites, developed in structureless or laminated patterns, appear to dominate the continental slope and the 2700–3600-m deep depressions of Samaria, Messara, and Gortys. These deposits are the result of successive mass transport events and turbidity currents. Over-steepening caused by strike–slip shearing associated with extensional tectonic activity in the shallow crustal levels, shaking due to significant seismic activity, and the presence of weak sediment layers are responsible for frequent triggering of slope failures and the subsequent formation of turbidity currents on the Gavdos slope. On the Cretan slope, sediments channeled as turbidity currents through canyons proved to be the major delivery mechanism, together with debris flows. Subordinate contributions of hemipelagic sediments occur only in the Messara basin. Moreover, steep non-incised slope areas and slope-confined canyons of the Gavdos slope were found to provide comparable sediment contribution with the fluvially connected canyons of the Cretan slope. [ABSTRACT FROM AUTHOR]

Since the Pliocene, rift basins have developed in the North Evia region at the south-western extension of the North Anatolian Fault. North Evia, therefore, is a key area for investigating Plio-Quaternary deformation within the diffuse Anatolian-Aegean–Eurasian plate boundary. In this study, we present a detailed map of offshore faults in the North Evia region based on three seismic reflection surveys: an airgun (2004) and two very high-resolution Sparker (2017 and 2021) single-channel surveys. Careful and systematic interpretation of these datasets revealed i) the identification of a new basin (Skiathos Basin) located at the western extension of the North Anatolian Fault and ii) two main fault sets striking oblique to the active N–S-directed extension. The seismicity analysis of the study area reveals pure strike-slip displacements along faults previously identified as normal. The NW–SE-striking faults bordering the North Evia Gulf rift are characterised by left-lateral displacements, and the NE–SW faults present dextral focal mechanisms, following the kinematic character of the North Anatolian Fault. We show that dextral strike-slip deformation recently occurred (in the late Quaternary) in the south-western extension of the North Anatolian Fault, suggesting the significant role of this fault system in the complex structural development of the North Evia region. • New seismic profiles in the western extension of North Anatolian Fault. • Mapping offshore fault networks in the North Evia region, Central Greece. • Evidence for a new basin between Sporades Islands and North Evia: Skiathos Basin. • Active strike-slip displacements along NW-SE and NE-SW striking faults. [ABSTRACT FROM AUTHOR]