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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]

Abstract: We present a review of our work on data acquired by GEOSTAR-class (GEophysical and Oceanographic STation for Abyssal Research) observatories deployed at three EMSO (European Multidisciplinary Seafloor and water-column Observatory; http://www.emso-eu.org) sites in southern European waters where strong geo-hazards are present: the Western Iberian Margin, the Western Ionian Sea, the Marmara Sea, and the Marsili basin in the Tyrrhenian Sea. A procedure for multiparameter data quality control is described. Then we explain why the seafloor is an interesting observation point for geophysical parameters and how it differs from land sites. We consider four interesting geophysical phenomena found at the EMSO sites that are related to geo-hazard. In the first case, we show how unknown seismicity and landslides in the Western Ionian Sea were identified and roughly localised through a single-sensor analysis based on the seismometer. In the second case, we concentrate on the problem of near-coast tsunami generation and describe a Tsunami Early Warning Detection (TEWD) system, tested in the Western Iberian Margin and currently operating in real time at the Western Ionian site. In the third case, we consider two large volcanoes in the central Mediterranean area, Mt. Etna and the Marsili seamount. Signals from the seismometer and gravimeter recorded at the seafloor at 2100m b.s.l. show various phases of Mt. Etna's 2002–2003 eruption. For the less-known Marsili we illustrate how several indicators coming from different sensors point to hydrothermal activity. A vector magnetometer at the two volcanic sites helps identify the magnetic lithospheric depth. In the fourth and final case, we present a multiparameter analysis which was focused on finding possible correlations between methane seepage and seismic energy release in the Gulf of Izmit (Marmara Sea). [Copyright &y& Elsevier]

After the 1999 Izmit earthquake (Mw7.4), along the North-Anatolian Fault (NAF), an increase in gas emissions from the seafloor of the Sea of Marmara was observed. Using a multidisciplinary approach, that includes a combined analysis of high-resolution marine geophysical and gas-geochemical data, we determined the character of gas/fluid emissions and their spatial relationship with tectonic structures in the Darıca Basin (Gulf of Izmit), close to the western termination of the 1999 earthquake surface rupture. Data collected during several oceanographic expeditions allowed us to investigate the fine structure of active fault branches, as well as the geochemical signature of the cold seeps. We observed that gas emissions at the seafloor of the Darıca Basin are mostly constituted by biogenic CH4, and are aligned along strike-slip and transtensional fault segments. Although maximum CH4 concentrations were measured in correspondence of transtensional strands, we suggest that the biogenic CH4 emissions found along strike-slip segments, showing a relatively low gas background noise and a potential to increase during seismic events, are more suitable to study relationships between gas expulsion and the earthquake cycle. [ABSTRACT FROM AUTHOR]

The question of whether material stiffness enhances cell adhesion and clustering is still open to debate. Results from the literature are seemingly contradictory, with some reports illustrating that adhesion increases with surface stiffness and others suggesting that the performance of a system of cells is curbed by high values of elasticity. To address the role of elasticity as a regulator in neuronal cell adhesion and clustering, we investigated the topological characteristics of networks of neurons on polydimethylsiloxane (PDMS) surfaces - with values of elasticity (E) varying in the 0.55-2.65 MPa range. Results illustrate that, as elasticity increases, the number of neurons adhering on the surface decreases. Notably, the small-world coefficient - a topological measure of networks - also decreases. Numerical simulations and functional multi-calcium imaging experiments further indicated that the activity of neuronal cells on soft surfaces improves for decreasing E. Experimental findings are supported by a mathematical model, that explains adhesion and clustering of cells on soft materials as a function of few parameters - including the Young's modulus and roughness of the material. Overall, results indicate that - in the considered elasticity interval - increasing the compliance of a material improves adhesion, improves clustering, and enhances communication of neurons., (© 2024. The Author(s).)

Background and Objectives: Among individuals with normal glucose tolerance (NGT), subjects with high levels of plasma glucose (≥155 mg/dL) at sixty minutes during an oral glucose tolerance test (1h-OGTT) are at an increased risk of developing type 2 diabetes. We investigated the association between the triglycerides and glucose (TyG) index, a novel marker of insulin resistance, with 1h-OGTT glucose plasma concentrations., Material and Methods: 1474 non-diabetic Caucasian subjects underwent a 75 g OGTT and were divided into two groups according to the cutoff 1h-OGTT plasma glucose < 155 mg/dL (NGT-1h-low) and ≥ 155 mg/dL (NGT-1h-high). The TyG index was calculated as ln [fasting triglycerides (milligrams per deciliter) × fasting blood glucose (milligrams per deciliter)/2]. Multivariable linear and logistic regression analyses were used to establish the contribution of the TyG index to the variability of 1h-OGTT glucose, and how the former affected the risk of being NGT-1h-high., Results: 1004 individuals were NGT-1h-low and 470 were NGT-1h-high. The TyG index was higher for NGT-1h-high ( p = 0.001) individuals, and it was an independent factor influencing 1h-OGTT glycemia (β = 0.191, p < 0.001) after correcting for age, sex, and BMI. The TyG index was the strongest marker associated with the risk of being NGT-1h-high (OR = 1.703, CI 95% 1.34-2.17, p < 0.001) when compared with FPG (OR = 1.054, CI 95% 1.04-1.07, p < 0.001) and the HOMA-IR (OR = 1.156, CI 95% 1.08-1.23, p < 0.001)., Conclusions: Our study demonstrated that the TyG index, an efficient and cost-effective marker of insulin resistance, is associated with the variability of early post-challenge glucose levels and is an independent marker of being NGT-1h-high.

Here we review probing biological processes initiated by the deposition of droplets on surfaces by micro- and nanobeam X-ray scattering techniques using synchrotron radiation and X-ray free-electron laser sources. We review probing droplet evaporation on superhydrophobic surfaces and reactions with substrates, basics of droplets deposition and flow simulations, droplet deposition techniques and practical experience at a synchrotron beamline. Selected applications with biological relevance will be reviewed and perspectives for the latest generation of high-brilliance X-ray sources discussed., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Marinaro, Graceffa and Riekel.)

The method of realizing nanostructures using porous alumina templates has attracted interest due to the precise geometry and cheap cost of nanofabrication. In this work, nanoporous alumina membranes were utilized to realize a forest of nanowires, providing a bottom-up nanofabrication method suitable for surface-enhanced Raman spectroscopy (SERS). Gold and iron were electroplated through the straight channels of the membrane. The resulting nanowires are, indeed, made of an active element for plasmonic resonance and SERS as the hexagonal distribution of the nanowires and the extreme high density of the nanowires allows to excite the plasmon and detect the Raman signal. The method to reduce the distance between pores and, consequently, the distance of the nanowires after electrodeposition is optimized here. Indeed, it has been predicted that the light intensity enhancement factor is up to 10 12 when the gap is small than 10 nm. Measurements of Raman signal of thiol groups drying on the gold nanowires show that the performance of the device is improved. As the thiol group can be linked to proteins, the device has the potential of a biosensor for the detection of a few biomolecules. To assess the performance of the device and demonstrate its ability to analyze biological solutions, we used it as SERS substrates to examine solutions of IgG in low abundance ranges. The results of the test indicate that the sensor can convincingly detect biomolecules in physiologically relevant ranges.

Aqueous solution droplets are supported quasi contact-free by superhydrophobic surfaces. The convective flow in evaporating droplets allows the manipulation and control of biological molecules in solution. In previous works, super-hydrophobic drops on nano-patterned substrates have been used to analyze otherwise undetectable species in extremely low concentration ranges. Here, we used particle image velocimetry (PIV) for studying the flow field in water droplets containing polystyrene particles on a pillared silicon super-hydrophobic chip. The particles describe vortex-like motions around the droplet center as long as the evaporating droplet maintains a spherical shape. Simulations by a Finite Element Method (FEM) suggest that the recirculating flow is due to the temperature gradient along the droplet rim, generating a shear stress. Notably, the characteristics of the internal flow can be modulated by varying the intensity of the temperature gradient along the drop. We then used the flow-field determined by experiments and an approximate form of the Langevin equation to examine how particles are transported in the drop as a function of particle size. We found that larger particles with an average size of μ36&nbsp;μm are preferentially transported toward the center of the substrate, differently from smaller particles with a 10-fold lower size that are distributed more uniformly in the drop. Results suggest that solutions of spherical particles on a super-hydrophobic chip can be used to separate soft matter and biological molecules based on their size, similarly to the working principle of a time-of-flight (ToF) mass analyzer, except that the separation takes place in a micro-sphere, with less space, less time, and less solution required for the separation compared to conventional ToF systems.

The adhesion, proliferation, and migration of cells over nanomaterials is regulated by a cascade of biochemical signals that originate at the interface of a cell with a substrate and propagate through the cytoplasm to the nucleus. The topography of the substrate plays a major role in this process. Cell adhesion molecules (CAMs) have a characteristic size of some nanometers and a range of action of some tens of nanometers. Controlling details of a surface at the nanoscale-the same dimensional over which CAMs operate-offers ways to govern the behavior of cells and create organoids or tissues with heretofore unattainable precision. Here, using electrochemical procedures, we generated mesoporous silicon surfaces with different values of pore size (PS≈11 nm and PS≈21 nm), roughness (Ra≈7 nm and Ra≈13 nm), and fractal dimension (Df≈2.48 and Df≈2.15). Using electroless deposition, we deposited over these substrates thin layers of gold nanoparticles. Resulting devices feature (i) nanoscale details for the stimulation and control of cell assembly, (ii) arrays of pores for drug loading/release, (iii) layers of nanostructured gold for the enhancement of the electromagnetic signal in Raman spectroscopy (SERS). We then used these devices as cell culturing substrates. Upon loading with the anti-tumor drug PtCl (O,O'-acac)(DMSO) we examined the rate of adhesion and growth of breast cancer MCF-7 cells under the coincidental effects of surface geometry and drug release. Using confocal imaging and SERS spectroscopy we determined the relative importance of nano-topography and delivery of therapeutics on cell growth-and how an unbalance between these competing agents can accelerate the development of tumor cells.

The COronaVIrus Disease-19 (COVID-19) has been associated with thromboembolic complications, but evidence on its impact on hemorrhagic risk are still scarce. We describe a case of COVID-19 with hemorrhagic complication in the post-acute phase of the disease. The patient was a 93-year-old woman admitted to a post-acute care unit for COVID-19 patients in northern Italy. The patient's medical history included moderate cognitive impairment, atrial fibrillation under oral anticoagulation (warfarin 2.5 mg and 3.75 mg on alternate days, showing stable PT-INR values since October 2018), and arterial hypertension. The patient was affected by COVID-19, treated with supportive therapy. In the post-acute phase of the disease, the patient presented with melena and showed a marked elevation of PT-INR of 25.1. She was treated with venous infusion of three-factor prothrombin complex concentrate and vitamin K until PT-INR reduction. After 5 days, blood analyses revealed normal hemoglobin, PT-INR 2.15, and a slight alteration of liver function. This case supports a strong impact of the infection on the coagulative pattern not only pro-thrombotically but also by increasing hemorrhagic risk. Special attention should therefore be paid to COVID-19 patients under anticoagulation with vitamin K antagonist and a shift to heparin treatment until illness resolution may be a safe option in these individuals., Competing Interests: Conflict of InterestThe authors declare that they have no conflict of interest., (© Springer Nature Switzerland AG 2020.)

In this paper, we propose the use of a standing nanowires array, constituted by plasmonic active gold wires grown on iron disks, and partially immersed in a supporting alumina matrix, for surface-enhanced Raman spectroscopy applications. The galvanic process was used to fabricate nanowires in pores of anodized alumina template, making this device cost-effective. This fabrication method allows for the selection of size, diameter, and spatial arrangement of nanowires. The proposed device, thanks to a detailed design analysis, demonstrates a broadband plasmonic enhancement effect useful for many standard excitation wavelengths in the visible and NIR. The trigonal pores arrangement gives an efficiency weakly dependent on polarization. The devices, tested with 633 and 830 nm laser lines, show a significant Raman enhancement factor, up to around 6 × 10⁴, with respect to the flat gold surface, used as a reference for the measurements of the investigated molecules.

Understanding micro-seismicity is a critical question for earthquake hazard assessment. Since the devastating earthquakes of Izmit and Duzce in 1999, the seismicity along the submerged section of North Anatolian Fault within the Sea of Marmara (comprising the "Istanbul seismic gap") has been extensively studied in order to infer its mechanical behaviour (creeping vs locked). So far, the seismicity has been interpreted only in terms of being tectonic-driven, although the Main Marmara Fault (MMF) is known to strike across multiple hydrocarbon gas sources. Here, we show that a large number of the aftershocks that followed the M 5.1 earthquake of July, 25 th 2011 in the western Sea of Marmara, occurred within a zone of gas overpressuring in the 1.5-5 km depth range, from where pressurized gas is expected to migrate along the MMF, up to the surface sediment layers. Hence, gas-related processes should also be considered for a complete interpretation of the micro-seismicity (~M < 3) within the Istanbul offshore domain.

In recent years, an increasing number of surveys have definitively confirmed the seasonal presence of fin whales (Balaenoptera physalus) in highly productive regions of the Mediterranean Sea. Despite this, very little is yet known about the routes that the species seasonally follows within the Mediterranean basin and, particularly, in the Ionian area. The present study assesses for the first time fin whale acoustic presence offshore Eastern Sicily (Ionian Sea), throughout the processing of about 10 months of continuous acoustic monitoring. The recording of fin whale vocalizations was made possible by the cabled deep-sea multidisciplinary observatory, "NEMO-SN1", deployed 25 km off the Catania harbor at a depth of about 2,100 meters. NEMO-SN1 is an operational node of the European Multidisciplinary Seafloor and water-column Observatory (EMSO) Research Infrastructure. The observatory was equipped with a low-frequency hydrophone (bandwidth: 0.05 Hz-1 kHz, sampling rate: 2 kHz) which continuously acquired data from July 2012 to May 2013. About 7,200 hours of acoustic data were analyzed by means of spectrogram display. Calls with the typical structure and patterns associated to the Mediterranean fin whale population were identified and monitored in the area for the first time. Furthermore, a background noise analysis within the fin whale communication frequency band (17.9-22.5 Hz) was conducted to investigate possible detection-masking effects. The study confirms the hypothesis that fin whales are present in the Ionian Sea throughout all seasons, with peaks in call detection rate during spring and summer months. The analysis also demonstrates that calls were more frequently detected in low background noise conditions. Further analysis will be performed to understand whether observed levels of noise limit the acoustic detection of the fin whales vocalizations, or whether the animals vocalize less in the presence of high background noise.

The evaporation of single droplets of colloidal tobacco mosaic virus (TMV) nanoparticles on a superhydrophobic surface with a hexagonal pillar-pattern results in the formation of coffee-ring type residues. We imaged surface features by optical, scanning electron, and atomic force microscopies. Bulk features were probed by raster-scan X-ray nanodiffraction. At ∼100 pg/μL nanoparticle concentration, the rim of the residue connects to neighboring pillars via fibrous extensions containing flow-aligned crystalline domains. At ∼1 pg/μL nanoparticle concentration, nanofilaments of ≥80 nm diameter and ∼20 μm length are formed, extending normal to the residue-rim across a range of pillars. X-ray scattering is dominated by the nanofilament form-factor but some evidence for crystallinity has been obtained. The observation of sheets composed of stacks of self-assembled nanoparticles deposited on pillars suggests that the nanofilaments are drawn from a structured droplet interface.

The human brain is a tightly interweaving network of neural cells where the complexity of the network is given by the large number of its constituents and its architecture. The topological structure of neurons in the brain translates into its increased computational capabilities, low energy consumption, and nondeterministic functions, which differentiate human behavior from artificial computational schemes. In this manuscript, we fabricated porous silicon chips with a small pore size ranging from 8 to 75 nm and large fractal dimensions up to Df ∼ 2.8. In culturing neuroblastoma N2A cells on the described substrates, we found that those cells adhere more firmly to and proliferate on the porous surfaces compared to the conventional nominally flat silicon substrates, which were used as controls. More importantly, we observed that N2A cells on the porous substrates create highly clustered, small world topology patterns. We conjecture that neurons with a similar architecture may elaborate information more efficiently than in random or regular grids. Moreover, we hypothesize that systems of neurons on nano-scale geometry evolve in time to form networks in which the propagation of information is maximized.

We developed a new generation of superhydrophobic chips optimized for probing ultrasmall sample quantities by X-ray scattering and fluorescence techniques. The chips are based on thin Si3N4 membranes with a tailored pattern of SU-8 photoresist pillars. Indeed, aqueous solution droplets can be evaporated and concentrated at predefined positions using a non-periodic pillar pattern. We demonstrated quantitatively the deposition and aggregation of gold glyconanoparticles from the evaporation of a nanomolar droplet in a small spot by raster X-ray nanofluorescence. Further, raster nanocrystallography of biological objects such as rod-like tobacco mosaic virus nanoparticles reveals crystalline macro-domain formation composed of highly oriented nanorods.

Droplets on artificially structured superhydrophobic surfaces represent quasi contact-free sample environments which can be probed by X-ray microbeams and nanobeams in the absence of obstructing walls. This review will discuss basic surface wettability concepts and introduce the technology of structuring surfaces. Quasi contact-free droplets are compared with contact-free droplets; processes related to deposition and evaporation on solid surfaces are discussed. Droplet coalescence based on the electrowetting effect allows the probing of short-time mixing and reaction processes. The review will show for several materials of biological interest that structural processes related to conformational changes, nucleation and assembly during droplet evaporation can be spatially and temporally resolved by raster-scan diffraction techniques. Orientational ordering of anisotropic materials deposited during solidification at pinning sites facilitates the interpretation of structural data.

Porous silicon (PSi) is a promising material in several biomedical applications because of its biocompatibility and biodegradability. Despite the plethora of studies focusing on the interaction of cells with micrometer and submicro geometrical features, limited information is available on the response of cells to substrates with a quasi-regular distribution of nanoscopic pores. Here, the behavior of four different cell types is analyzed on two mesoporous (MeP) silicon substrates, with an average pore size of ∼5 (MeP1) and ∼20 nm (MeP2), respectively. On both MeP substrates, cells are observed to spread and adhere in a larger number as compared to flat silicon wafers. At all considered time points, the surface density of the adhering cells nd is larger on the PSi substrate with the smaller average pore size (MeP1). At 60 h, nd is from ∼1.5 to 5 times larger on MeP1 than on MeP2 substrates, depending on the cell type. The higher rates of proliferation are observed for the two neuronal cell types, the mouse neuroblastoma cells (N2A) and the immortalized human cortical neuronal cells (HCN1A). It is speculated that the higher adhesion on MeP1 could be attributed to a preferential matching of the substrate topography with the recently observed multiscale molecular architecture of focal adhesions. These results have implications in the rational development of PSi substrates for supporting cell adhesion and controlling drug release in implants and scaffolds for tissue engineering applications.