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An improved weather-forecast-based link-budget design technique for space-to-Earth links is described. The aim is the stochastic optimization of both transmission symbol rate and received signal-to-noise ratio. The proposed radiometeorological operations prediction (RadioMetOP) model takes into account the forecast uncertainty by a space–time ensemble method exploiting the temporal evolution of the predicted radiometeorological variables over the weather-forecast spatial grid. The unique possibility of testing and validating the RadioMetOP model is presented, thanks to the $Ka$ -band downlink measurements available from the support of the European Space Agency’s antenna tracking network to deep-space Hayabusa-2 (HB2) mission, operated by the Japan Aerospace Exploration Agency. First, the RadioMetOP model accuracy is tested by comparing the signal-to-noise ratio, measured during the transmission periods, with the simulated one, properly scaled to the symbol rate operated by HB2, finding correlation values of 0.9 that confirm the effectiveness of the proposed approach. Second, the $a$ posteriori analysis of the optimization process is accomplished, showing that depending on the considered criteria for the link-budget optimization, the use of the RadioMetOP model would have allowed a transmitted data volume more than doubled and an average signal-to-noise ratio gain between 2.1 and 3.8 dB.

Monoatomic nanosheets can form 2-dimensional channels with tunable chemical properties, for ion storage and filtering applications. Here, we demonstrate transport of K+, Na+, and Li+ cations and F- and Cl- anions on the centimeter scale in graphene oxide membranes (GOMs), triggered by an electric bias. Besides ion transport, the GOM channels foster also the aggregation of the selected ions in salt crystals, whose composition is not the same as that of the pristine salt present in solution, highlighting the difference between the chemical environment in the 2D channels and in bulk solutions.

Label free biosensors based on electrolyte gated organic transistors (EGOTs) are ultra-sensitive and versatile sensing devices. The dose curve represents the change of the sensor signal as a function of the concentration of the target analyte, and, under the hypothesis of dynamic equilibrium between the surface-bound probe and its target partner, can be fitted to adsorption isotherms. In this work, we show that the data obtained from both the OECT and EGOFET Interleukin-6 (IL-6) biosensors are best fitted by the Frumkin isotherm compared to the widely adopted Langmuir and Hill isotherms. Comparable values of the equilibrium association constant Ka and the Frumkin interaction parameter g′ are obtained with both OECT and EGOFET sharing the same functionalization of the gate electrode. Our study unambiguously shows that the biosensor response is, to a large extent, due to the specific binding at the gate/electrolyte interface, and that is viable to investigate the thermodynamics of biorecognition. Moreover, the electrostatic repulsions between adsorbed probe–target pairs are shown to decrease the effective equilibrium association constant as coverage increases, thus causing a loss of sensitivity for concentrations above the threshold limit 1/|g′|.

Charge injection in Organic Field Effect Transistors is investigated by monitoring in real-time the electrical conduction, while in situ growing pentacene films. The source and drain electrodes are made of gold functionalized with alkanethiol Self-Assembled Monolayers (SAMs), whose number of carbon atoms ranges from 5 to 10. Measuring the current flowing into the channel allows us to establish a correlation between the charge injection and the pentacene film growth. In particular, the thickness dependence of both the charge mobility and the charge carrier accumulation can be explained in terms of the molecular order at the interface between the pentacene films and the SAMs. Specifically, the threshold voltage, contact resistance and temperature-dependent constant exhibit parabolic trends for increasing alkanethiol chain length. Conversely, both the band mobility and the charge mobility are characterized by oscillations that follow an odd–even trend with a linear decay for increasing number of the carbon atoms. These results corroborate the theoretical interpretation, previously proposed by Stoliar et al., that the odd–even effect is ascribable to the order degree and orientation of the pentacene molecules interacting with the SAMs, while the parabolic trend depends on the chain length of the alkanethiol SAMs.

A general single-step approach is introduced for the green fabrication of hybrid biosensors from water dispersion. The resulting device integrates the semiconducting properties of a carbon nanotube (CNT) and the functionality of a protein. In the initial aqueous phase, the protein (viz., lysozyme [LZ]) disperses the (6,5)CNT. Drop-casting of the dispersion on a test pattern (a silicon wafer with interdigitated Au source and drain electrodes) yields a fully operating, robust, electrolyte-gated transistor (EGT) in one step. The EGT response to biorecognition is then assessed using the LZ inhibitorN-acetyl glucosamine trisaccharide. Analysis of the output signal allows one to extract a protein-substrate binding constant in line with values reported for the free (without CNT) system. The methodology is robust, easy to optimize, redirectable toward different targets and sets the grounds for a new class of CNT-protein biosensors that overcome many limitations of the technology of fabrication of CNT biosensors

Poly(3,4-ethylentedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) is one of the most studied materials for organic bioelectronics, supercapacitors and organic photovoltaics. Its low impedance is ascribed to the so-called volumetric capacitance, a property that phenomenologically correlates the capacitive coupling/charge storage in devices to the PEDOT:PSS volume/thickness. Here we investigate the correlation between the capacitance and the electroactive surface area (ESA) for large-volume spin-cast PEDOT:PSS electrodes. We measure the capacitance with cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS), and characterize the surface morphology by atomic force microscopy and X-ray photoelectron spectroscopy. Capacitance of PEDOT:PSS films scales with volume up to ~5 × 106 ?m3 but is saturated at larger volumes. This scaling behavior is paralleled by the scaling of the ESA, hence the ratio between the effective capacitance and ESA remains constant across the whole data set, thus showing that the specific areal capacitance is indeed the relevant material property of PEDOT:PSS. EIS data fit supports the experimental evidence obtained by CV, further revealing that the diffusion time constant is also saturated at high volumes. This supports the scenario where the effective capacitance relates to the ion accessible ESA, and shows that the saturation of the capacitance arises from a change of ion penetration from a diffusive (at small volumes) to a non-diffusive regime at large volumes.

The author has derived the closed-form dynamic equations for a planar musculoskeletal chain composed of a generic number n of rigid links connected by ideal revolute joints. Single-joint and multi-joint muscles have been modeled as linear force actuators that can span from one joint to all the joints of the chain. The generic shape and size of each individual link of the chain accounts for different alignments among the center of mass of the link, the centers of rotation of the joints that articulate the link with its neighbors, and the points of application of the muscle forces and the possible contact external resistances acting on the link. The joint torque and the reaction force acting on each joint have been determined in closed-form by analytical quantification of the unique contribution of each individual kinematic and kinetic variable: (1) force of each single-joint or multi-joint muscle spanning or non-spanning the joint, (2) weight and contact external resistances acting on each individual link of the chain, (3) position, angular velocity, and angular acceleration of each individual link of the chain. The analytical results derived in this study can be applied to multilink musculoskeletal chains with deep/superficial and segmental/global muscles.

The conditions of high hydraulic risk are mainly due to the interference between the river network and bridges, their relative access ramps and road embankments located in the floodplain. Actually, bridges are not always structurally adequate to withstand severe flood waves. In flood restoration works, there is an objective difficulty in implementing the structural safety of bridges because of historical, artistic and economic issues. Thus, the risk mitigation strategy often accounts for the assessment of the vulnerability degree of each bridge/road embankment according to an evaluation scale. Here we present a methodology regarding the classification of the vulnerability degree and its application to 84 works located in the alluvial area of the Tiber River, in the area of the Province of Perugia. For the purposes of a synthetic classification of works vulnerability, the individual assessed parameters are compared by means of subsequent contingency tables in order to compute the resulting vulnerability degree.

The photochemical core of every photosynthetic apparatus is the reaction center, a transmembrane enzyme that converts photons into charge-separated states across the biological membrane with an almost unitary quantum yield. We present a light-driven organic transistor architecture, which converts light into electrical current by exploiting the efficiency of this biological machinery. Proper surface tailoring enables the integration of the bacterial reaction center as photoactive element in organic transistors, allowing the transduction of its photogenerated voltage into photomodulation of the output current up to two orders of magnitude. The device architecture, termed Light-driven Electrolyte-Gated Organic Transistor (LEGOT), is the prototype of a new generation of low-power hybrid bio-optoelectronic organic devices.

The “pulsed electron deposition” (PED) technique, in which a solid target material is ablated by a fast, high-energy electron beam, was initially developed two decades ago for the deposition of thin films of metal oxides for photovoltaics, spintronics, memories, and superconductivity, and dielectric polymer layers. Recently, PED has been proposed for use in the biomedical field for the fabrication of hard and soft coatings. The first biomedical application was the deposition of low wear zirconium oxide coatings on the bearing components in total joint replacement. Since then, several works have reported the manufacturing and characterization of coatings of hydroxyapatite, calcium phosphate substituted (CaP), biogenic CaP, bioglass, and antibacterial coatings on both hard (metallic or ceramic) and soft (plastic or elastomeric) substrates. Due to the growing interest in PED, the current maturity of the technology and the low cost compared to other commonly used physical vapor deposition techniques, the purpose of this work was to review the principles of operation, the main applications, and the future perspectives of PED technology in medicine.

This work describes the operative experimentation of a weather-forecast based satellite link-budget approach at Ka-band (named RMOP) during 6 months of collaboration with JAXA and ESA within Hayabusa-2 deep-space mission. Operative link-budget design was performed 24 hours before each scheduled transmission window providing JAXA and ESA with optimized symbol-rates (to adopt during the transmission) and the corresponding expected signal-to-noise ratio values allowing a real-time monitoring of the predicted atmospheric channel status. The comparison between simulations and measurements proves the accuracy of the RMOP tool with correlation values higher than 0.9, bias lower than 0.8 dB and error standard deviation lower than 0.7 dB. The optimization analysis confirms the strong potential of the RMOP approach providing gain values higher than 5 dB in terms of signal-to-noise ratio and higher than 100% in terms of transmitted data-volume. These results pave the way to an operative scheduling of a weather-forecast based link-budget approach for future satellite missions.

The need for effective and reliable damage detection and localization systems is growing in several engineering fields, in particular in water impact problems characterized by impulsive loading conditions, high amplitude vibrations and large local deformations. In this paper, we further develop the approach presented in previous works to detect damage of water-impacting structures. Specifically, we provide a set of experimental tests on a flexible plastic cylinder impacting the water after a 50 cm free fall. The cylindrical specimen is artificially damaged in a known position. Strain measurements are performed through a set of nine fiber Bragg gratings distributed along the circumference of a cylinder section. We show that strain sensors can be used as reference sensors, for structure displacements reconstruction, and control sensors, for damage detection purposes, and the computation of the difference between measured and expected deformation may allow damage detection. Moreover, we investigate how exchanging control and reference sensors in the same sensor arrangement affect damage detection and localization.

Ground-based microwave radiometer (MWR) observations of downwelling brightness temperature (span classCombining double low line"inline-formula") are commonly used to estimate atmospheric attenuation at relative transparent channelsfor radio propagation and telecommunication purposes. The atmospheric attenuation is derived from span classCombining double low line"inline-formula"span by inverting the radiative transfer equation with a priori knowledge of the mean radiating temperature (

An overview of cytokine biosensing is provided, with a focus on the opportunities provided by organic electronic platforms for monitoring these inflammation biomarkers which manifest at ultralow concentration levels in physiopathological conditions. Specifically, two of the fields state-of-the-art technologies-organic electrochemical transistors (OECTs) and electrolyte gated organic field effect transistors (EGOFETs)-and their use in sensing cytokines and other proteins associated with inflammation are a particular focus. The overview will include an introduction to current clinical and "gold standard" quantification techniques and their limitations in terms of cost, time, and required infrastructure. A critical review of recent progress with OECT- and EGOFET-based protein biosensors is presented, alongside a discussion onthe future of these technologies in the years and decades ahead. This is especially timely as the world grapples with limited healthcare diagnostics during the Coronavirus disease (COVID-19)pandemic where one of the worst-case scenarios for patients is the "cytokine storm." Clearly, low-cost point-of-care technologies provided by OECTs and EGOFETs can ease the global burden on healthcare systems and support professionals by providing unprecedented wealth of data that can help to monitor disease progression in real time. Funding Agencies|European Unions Horizon 2020 research and innovation program under the Marie Skodowska-Curie Grant [813863]; Swedish Foundation for Strategic ResearchSwedish Foundation for Strategic Research; Knut and Alice Wallenberg FoundationKnut & Alice Wallenberg Foundation

Sun-tracking microwave (ST-MW) radiometry is a ground-based technique where the Sun is used as a beacon source to infer the atmospheric path attenuation in all-weather conditions. ST-MW radiometry shows an appealing potential for overcoming the difficulties to perform satellite-to-Earth radiopropagation experiments in the unexplored millimeter-wave and submillimeter-wave frequency region, especially where experimental data from beacon receivers are not available. The theoretical framework, the ad hoc procedures and data processing will be presented, together with the estimate of the overall error budget. The applications and challenges during field deployments, such as the recent WRad campaign in Italy based on ST-MW data analysis, funded by ESA and carried out together with AFRL (NY, USA), will be discussed.

This study is focused on the particular advantages of organic-based devices to measure cells that do not generate action potentials, also known as non-electrogenic cells. While there is a vast literature about the application of organic conductors to measure neurons, cardiomyocytes and brain tissues, electrical measurements of non-electrogenic cells are rare. This is because non-electrogenic cells generate weak signals with frequencies below 1 Hz. Designing low noise devices in a millihertz frequency range is extremely challenging due to the intrinsic thermal and 1/f type noise generated by the sensing electrode. Here, we demonstrate that the coating of cellulose nanofibers with conducting PEDOT:PSS ink allows the fabrication of a nanostructured surface that establishes a low electrical double-layer resistance with liquid solutions. The low interfacial resistance combined with the large effective sensing area of PEDOT:PSS electrodes minimizes the thermal noise and lowers the amplitude detection limit of the sensor. The electrode noise decreases with frequency from 548 nV r.m.s at 0.1 Hz to a minimum of 6 nV r.m.s for frequencies higher than 100 Hz. This low noise makes it possible to measure low frequency bioelectrical communication signals, typical of non-electrogenic cells, that have until now been difficult to explore using metallic-based microelectrode arrays. The performance of the PEDOT:PSS-based electrodes is demonstrated by recording signals generated by populations of glioma cells with a signal-to-noise ratio as high as 140. Portuguese Foundation for Science and Technology (FCT/MCTES)Portuguese Foundation for Science and Technology FEDER under the PT 2020 Partnership Agreement "Implantable organic devices for advanced therapies", INNOVATE [PTDC/EEIAUT/5442/2014] Instituto de Telecomunicacoes, IT [UIDB/EEA/50008/2020] Centro de Ciencias do Mar, CCMar [UIDB/Multi/04326/2020] CICECO -Aveiro Institute of Materials [UIDB/50011/2020, UIDP/50011/2020] FCT, under the "Norma Transit.oria" project CT0020 [DL57/2016/CP1361] FCTPortuguese Foundation for Science and TechnologyEuropean Commission [SFRH/BD/148688/2019] info:eu-repo/semantics/publishedVersion

International audience; Abstract Within the GEN-COVID Multicenter Study, biospecimens from more than 1000 SARS-CoV-2 positive individuals have thus far been collected in the GEN-COVID Biobank (GCB). Sample types include whole blood, plasma, serum, leukocytes, and DNA. The GCB links samples to detailed clinical data available in the GEN-COVID Patient Registry (GCPR). It includes hospitalized patients (74.25%), broken down into intubated, treated by CPAP-biPAP, treated with O 2 supplementation, and without respiratory support (9.5%, 18.4%, 31.55% and 14.8, respectively); and non-hospitalized subjects (25.75%), either pauci- or asymptomatic. More than 150 clinical patient-level data fields have been collected and binarized for further statistics according to the organs/systems primarily affected by COVID-19: heart, liver, pancreas, kidney, chemosensors, innate or adaptive immunity, and clotting system. Hierarchical clustering analysis identified five main clinical categories: (1) severe multisystemic failure with either thromboembolic or pancreatic variant; (2) cytokine storm type, either severe with liver involvement or moderate; (3) moderate heart type, either with or without liver damage; (4) moderate multisystemic involvement, either with or without liver damage; (5) mild, either with or without hyposmia. GCB and GCPR are further linked to the GCGDR, which includes data from whole-exome sequencing and high-density SNP genotyping. The data are available for sharing through the Network for Italian Genomes, found within the COVID-19 dedicated section. The study objective is to systematize this comprehensive data collection and begin identifying multi-organ involvement in COVID-19, defining genetic parameters for infection susceptibility within the population, and mapping genetically COVID-19 severity and clinical complexity among patients.

Plum Pox Virus (PPV) is the pathogen responsible for Sharka, a highly infectious disease affecting stone fruit trees and causing severe economic damages, which can be only contained through early-detection and frequent monitoring. We propose a bioelectronic PPV biosensor, based on a electrolyte-gated organic field-effect transistor (EGOFET), for the specific detection of PPV in plant extracts with a sub ng/ml detection limit. The sensing unit of the biosensor is based on anti-PPV antibodies, uniformly oriented on the gold gate electrode by using a sub-monolayer of Protein G. The sensitivity and dynamic range of the EGOFET-based biosensor are comparable to those of commercially available platforms for detection of plant pathogens. This novel electronic immunosensor is compatible with low-cost fabrication procedures and can be easily reconfigured into a fully portable device to be operated in greenhouse and in the field orchards.

none 3 no Electric field; Density functional theory; organic field effect transistors; dimerization process Density functional theory (DFT) calculations were used to assess the effect of electric fields of varying magnitudes and directions on the molecular structure of pentacene and other acenes. The aim is to understand the response of acenes in organic field effect transistors, specifically the structure of the first monolayer(s) deposited on the gate dielectric, where the transversal electric field and the charge carrier density are largest and charge transport occurs. Pentacene cycloaddition can be enhanced by the application of electric fields oriented along the direction of the forming bonds. Dimerization is likely to occur in low-density, disordered domains, such as grain boundaries or terrace edges. Together with other factors, dimerization could affect device performance leading to an irreversible decrease of mobility due to the creation of new trap states. Matta, Micaela; Biscarini, Fabio; Zerbetto, Francesco Matta, Micaela; Biscarini, Fabio; Zerbetto, Francesco

The controlled release of cell differentiating agents is crucial in many aspects of regenerative medicine. Here we propose the use of hybrid calcite single crystals as micro-carriers for the controlled and localized release of retinoic acid, which is entrapped within the crystalline lattice. The release of retinoic acid occurs only in the proximity of stem cells, upon dissolution of the calcite hybrid crystals that are dispersed in the fibrin scaffold. These hybrid crystals provide a sustained dosage of the entrapped agent. The environment provided by this composite scaffold enables differentiation towards neuronal cells that form a three-dimensional neuronal network.

Peptide aggregation into oligomers and fibrillar architectures is a hallmark of severe neurodegenerative pathologies, diabetes mellitus or systemic amyloidoses. The polymorphism of amyloid forms and their distribution are both effectors that potentially modulate the disease, thus it is important to understand the molecular basis of protein amyloid disorders through the interaction of the different amyloid forms with neural cells and tissues. Here we explore the effect of amyloid fibrils on the human neuroblastoma (SH-SY5Y) cell line in vitro. We control the kinetic of fibrillization of insulin at low pH and higher temperature. We use a multiscale characterization via fluorescence microscopy and multimodal scanning probe microscopy to correlate the number of cells and their morphology, with the finer details of the insulin deposits. Our results show that insulin aggregates deposited on neuroblastoma cell cultures lead to a progressive modification and decreased number of cells that correlates with the degree of fibrillization. SPM unravels that the aggregates strongly interact with the cell membrane, forming a stiff encase that possibly leads to an increased cell membrane stiffness and deficit in the metabolic exchanges between the cells and their environment. The presence of fibrils does not affect the number of cells at 24h whereas drop down to 60% is observed after 48h of incubation.

The aggregation of α-synuclein is a critical event in the pathogenesis of neurological diseases, such as Parkinson or Alzheimer. Here, we present a label-free sensor based on an Electrolyte-Gated Organic Field-Effect Transistor (EGOFET) integrated with microfluidics that allows for the detection of amounts of α-synuclein in the range from 0.25 pM to 25 nM. The lower limit of detection (LOD) measures the potential of our integrated device as a tool for prognostics and diagnostics. In our device, the gate electrode is the effective sensing element as it is functionalised with anti-(α-synuclein) antibodies using a dual strategy: i) an amino-terminated self-assembled monolayer activated by glutaraldehyde, and ii) the His-tagged recombinant protein G. In both approaches, comparable sensitivity values were achieved, featuring very low LOD values at the sub-pM level. The microfluidics engineering is central to achieve a controlled functionalisation of the gate electrode and avoid contamination or physisorption on the organic semiconductor. The demonstrated sensing architecture, being a disposable stand-alone chip, can be operated as a point-of-care test, but also it might represent a promising label-free tool to explore in-vitro protein aggregation that takes place during the progression of neurodegenerative illnesses., This work was funded by the EXPLORA project MAT2015-72760-EXP (Spanish Ministry) and ERC StG 2012–306826 e-GAMES (European Research Council FP7). The authors also thank the Spanish Ministry of Economy and Competitiveness, through the projects FANCY CTQ2016-80030-R, GENESIS PID2019-111682RB-I00 and “Severo Ochoa” Programme for Centers of Excellence in R&D (SEV-2015-0496), the Generalitat de Catalunya (2017-SGR-918) and the Networking Research Center on Bioengineering, Biomaterials, and Nanomedicine (CIBER-BBN). S. R. is enrolled in the PhD program of the Universitat Autònoma of Barcelona (UAB). The research leading to these results has also received funding from the People Programme (Marie Curie Actions) of the Seventh Framework Programme of the European Union (FP7/2007–2013) under Research Executive Agency Grant Agreement No. 600388 (TECNIOSpring programme), and from the Agency for Business Competitiveness of the Government of Catalonia, ACCIÓ. The Surface Plasmon Resonance (SPR) measurements were performed through the ICTS NANBIOSIS platform, more specifically in the Biodeposition and Biodetection Unit of the CIBER in Bioengineering, Biomaterials & Nanomedicine (CIBER-BBN) at the Catalan Institute of Nanoscience and Nanotechnology (ICN2). The microfluidic device design and fabrication were performed with funding from the European Union's Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement 764281 (AiPBAND), and Marie Skłodowska-Curie grant agreement 813863 (BORGES).

The design phase of an ESA project (MEKaP-MEO Ka-band Propagation) is described. The study, involving Politecnico di Milano, Sapienza Universita di Roma, Instituto de Telecomunicacoes-Aveiro Pole and Thales Alenia SpaceItalia, aims at characterizing the main properties of the atmospheric radio channel of a MEO Ka-band SatCom system. The propagation campaign, lasting at least two years and including four ground receivers, will rely on the MEO O3b Ka-band satellite constellation, which has key characteristics for propagation measurements, such as continuous observation time (at least one satellite is always visible) and global coverage up to mid-latitudes. The experimental data collected during the campaign will be used to test and improve the available propagation models for non-geostationary systems and to extend the experimental database of radio regulatory bodies such as the ITU-R.

The mean radiative temperature ( $T_{mr}$ ) is a key function controlling the sky noise temperature in microwave receiving systems. A generalized parametric prediction (GPP) model of $T_{mr}$ for microwave slant paths in all-weather conditions is formulated and presented. The proposed GPP model is aimed at being multifrequency and surface-temperature scaled, valid for elevation angles from 5° to 90° and for frequencies ranging from 5 to 95 GHz within the three transmission windows delimited by the water vapor and the oxygen absorption peaks. The core of the GPP model is a parametrization driven by a physically based radiative transfer approach taking into account extinction, emission, and multiple scattering. The expression of $T_{mr}$ is normalized to the surface temperature of the considered site. The GPP model is verified with measurements available from the multiinstrument Italian Satellite (ITALSAT) campaign in Spino d’Adda, Milan, Italy, in 1994–1997, obtaining a fractional mean error ranging from 0.045 to 0.068. A comparison of the GPP model with the current ITU-R model shows a reduction in the root mean square error up to about 20 and 30 K, depending on the considered frequency.

Phase-mode electrostatic force microscopy (EFM-Phase) is a viable technique to image surface electrostatic potential of silicon oxide stripes fabricated by oxidation scanning probe lithography, exhibiting an inhomogeneous distribution of localized charges trapped within the stripes during the electrochemical reaction. We show here that these nanopatterns are useful benchmark samples for assessing the spatial/voltage resolution of EFM-phase. To quantitatively extract the relevant observables, we developed and applied an analytical model of the electrostatic interactions in which the tip and the surface are modelled in a prolate spheroidal coordinates system, fitting accurately experimental data. A lateral resolution of ∼60 nm, which is comparable to the lateral resolution of EFM experiments reported in the literature, and a charge resolution of ∼20 electrons are achieved. This electrostatic analysis evidences the presence of a bimodal population of trapped charges in the nanopatterned stripes.

It is well known that amphiphilic cationic beta-cyclodextrins (am beta CDs) form nanovesicles able to release their cargo in aqueous solution upon applying different stimuli. In addition they can be selectively positioned onto substrates by unconventional soft lithography. This makes them a powerful tool for designing environments where different cues can be externally supplied to the cells helping to achieve good control of their fate. Lithographically controlled wetting (LCW) of am beta CD nanovesicles loaded with fluorescein isothiocyanate (FITC), am beta CD/FITC, has been used here to fabricate geometrically functionalized surfaces, thus achieving multiscale control of the cell environment. The am beta CD functionalization was strongly influenced by the surface energy of the underlying substrates that, according to their hydrophobicity, orient the am beta CD in a different way, thus "offering" different portions to the cells. The structure of the pattern was characterized both over large scales exploiting the FITC fluorescence and at the nanoscale by atomic force microscopy. Cell guidance and aCD/FITC cell internalization were demonstrated in human neuroblastoma SHSY5Y cells.

The water dispersion of the conductive polymer poly(3,4-ethylenedioxythiophene):poly(styrenesulfonic acid) (PEDOT:PSS) is one of the most used material precursors in organic electronics also thanks to its industrial production. There is a growing interest for conductive polymers that could be alternative surrogates or replace PEDOT:PSS in some applications. A recent study by our group compared electrodeposited PEDOT:Nafion vs PEDOT:PSS in the use for neural recordings. Here, we introduce an easy and reproducible synthetic protocol to prepare a water dispersion of PEDOT:Nafion. The conductivity of the pristine material is on the order of 2 S cm-1 and was improved up to ≈6 S cm-1 upon treatment with ethylene glycol. Faster ion transfer was assessed by electrochemical impedance spectroscopy (EIS), and, interestingly, an improved adhesion was observed for coatings of the new PEDOT:Nafion dispersion on glass substrates, even without the addition of the silane cross-linker needed for PEDOT:PSS. As proof of concept, we demonstrate the use of this novel water dispersion of PEDOT:Nafion in three different organic electronic device architectures, namely, an organic electrochemical transistor (OECT), a memristor, and an artificial synapse.

In situ atomic force microscopy (AFM) allowed us to investigate the evolution at the early stages of the growth of organic thin films. An ultrahigh-vacuum atomic force microscope, integrated with a Knudsen effusion cell for the sublimation of ?-sexithiophene (6T), continuously scans the same region during the deposition of sublimed molecules on native silicon oxide as a function of the substrate temperature. Noncontact AFM images acquired sequentially provide snapshots of the time evolution of the film morphology that is monitored up to the deposition of five monolayers. At all substrate temperatures, a Stranski-Krastanov growth mode of organic films is observed: the first two monolayers grow layer-by-layer (two-dimensional?2D), then films evolve into islands (three-dimensional?3D). Despite the apparent similarity, we find an anomalous dynamic scaling characterized by the abrupt change of the growth exponent ? vs substrate temperature. This novel transition, induced by the substrate temperature, is ascribed to the morphological transition from ziggurat islands to large terraces. The analysis of the evolution of the root-mean-square (RMS) roughness based on the distributed growth model underlines the role of down-hill mass transport for the growth of the first two monolayers, transport that is progressively hindered for the next monolayers.

Most of the photochemical activity of bacterial photosynthetic apparatuses occurs in the reaction center, a transmembrane protein complex which converts photons into chargeseparated states across the membrane with a quantum yield close to unity, fuelling the metabolism of the organism. Integrating the reaction center from the bacterium Rhodobacter sphaeroides onto electroactive surfaces, it is possible to technologically exploit the efficiency of this natural machinery to generate a photovoltage upon Near Infra-Red illumination, which can be used in electronic architectures working in the electrolytic environment such as electrolyte-gated organic transistors and bio-photonic power cells. Here, photovoltage generation in reaction center-based bio-hybrid architectures is investigated by means of chronopotentiometry, isolating the contribution of the functionalisation layers and defining novel surface functionalization strategies for photovoltage tuning.

Microelectrode arrays are used for recording and stimulation in neurosciences both in vitro and in vivo. The electrodeposition of conductive polymers, such as poly(3,4-ethylene dioxythiophene) (PEDOT), is widely adopted to improve both the in vivo recording and the charge injection limit of metallic microelectrodes. The workhorse of conductive polymers in the neurosciences is PEDOT:PSS, where PSS represents polystyrene-sulfonate. In this paper, the counterion is the fluorinated polymer Nafion, so the composite PEDOT:Nafion is deposited onto a flexible neural microelectrode array. PEDOT:Nafion coated electrodes exhibit comparable in vivo recording capability to the reference PEDOT:PSS, providing a large signal-to-noise ratio in a murine animal model. Importantly, PEDOT:Nafion exhibits a minimized polarization during electrical stimulation, thereby resulting in an improved charge injection limit equal to 4.4 mC cm-2 , almost 80% larger than the 2.5 mC cm-2 that is observed for PEDOT:PSS.

We report a dual gate/common channel organic transistor architecture designed for quantifying the concentration of one of the strands of miRNA-21 in solution. The device allows one to measure the differential response between two gate electrodes, viz. one sensing and one reference, both immersed in the electrolyte above the transistor channel. Hybridization with oligonucleotide in the picomolar regime induces a sizable reduction of the current flowing through the transistor channel. The device signal is reported at various gate voltages, showing maximum sensitivity in the sublinear regime, with a limit of detection as low as 35 pM. We describe the dose curves with an analytical function derived from a thermodynamic model of the reaction equilibria relevant in our experiment and device configuration, and we show that the apparent Hill dependence on analyte concentration, whose exponent lies between 0.5 and 1, emerges from the interplay of the different equilibria. The binding free energy characteristic of the hybridization on the device surface is found to be approximately 20% lower with respect to the reaction in solution, hinting to partially inhibiting effect of the surface and presence of competing reactions. Impedance spectroscopy and surface plasmon resonance (SPR) performed on the same oligonucleotide pair were correlated to the electronic current transduced by the EGOFET, and confirmed the selectivity of the biorecognition probe covalently bound on the gold surface.

The aim of this paper is to investigate the usability of high-frequency channels for deep-space (DS) transmissions exploiting radiometeorological forecast modeling. A previously developed model chain for DS link-budget optimization, based on numerical weather forecasts (WFs), is adopted. The latter, already tested at Ka-band, exploits the combination of a high-resolution mesoscale forecast model and a radiative transfer model to predict the atmospheric scenario and optimize received data volume (DV) during DS transmissions. To shift available Ka-band results to other frequencies, we apply frequency-scaling laws to extrapolate forecast path attenuation, link parameters, and maximum allowed bit-rate for data transmission. Exploiting the available WF-based methodology, we compute DV return for DS missions operating at $X$ -, $K$ -, Ka-, $Q$ -, and $W$ -bands in order to make a comparative study of the behavior of DS transmission-channels at these frequencies. Results show that, in terms of received DV, an innovative WF-based approach is more convenient than traditional methodologies and exhibits a trend similar to the benchmark (ideal case). Increasing link frequency, received DV increases up to $Q$ -band. From $Q$ - to $W$ -band, despite received DV does not increase significantly, lost data remain under reasonable values, thus making the $W$ -band suitable if coupled with a WF-based technique.

Our purpose was to study the tribological effects of surface texturing at the mesoscale, generally disregarded. We realized hemispherical dimples on 100Cr6 steel pins using a ns-pulsed Nd:YAG laser. Both radius and depth of the patterns fall in the very-low part of the micrometric scale, ranging respectively from 10 to 13 μm and from 4 to 6.5 μm. To map Stribeck curves, we used a pin-on-disk apparatus and a commercial motor oil as lubricant. The results confirm that the post-texturing lapping process is crucial to achieve a reduction in the coefficient of friction. These patterns show a tribological effect mainly in mixed lubrication regime, and partially in hydrodynamic regime. Even very small differences in radius and depth may induce very different response, evidencing the need of very fine tuning of the geometrical characteristics of the patterns. The lower friction was recorded for larger and deeper dimples. Friction reduction for increasing dimples density has been found as well. Endurance tests in boundary lubrication regime show a more stable coefficient of friction and a larger mean lifetime of patterned surfaces with respect to polished one. Furthermore, water-contact-angle tests show a weak hydrophobic effect for high aspect ratio patterns. However, no correlation was observed between wettability and tribological response.

Electrolyte‐gated organic field‐effect transistors (EGOFETs) exploit the transduction of interfacial phenomena, such as biorecognition or redox processes, into detectable changes of electrical response. Here, it is shown that, beyond sensing applications, EGOFETs may act effectively as memory devices, through the functionalization of the gate electrode with a self‐assembly monolayer comprising a switching molecule undergoing a large and persistent change of dipole moment, upon application of a small (0.6 V) programming potential. This first example of a switchable EGOFET device with memory retention is based on a tetrathiafulvalene derivative self‐assembled on gold and an aqueous buffer as electrolyte in a microfluidic assembly. Changes of the self‐assembled monolayer redox state lead to variations of the gate electrochemical potential and, as a consequence, the EGOFET's threshold voltage undergoes reversible shifts larger than 100 mV. The distinctive electrical readout upon different redox states opens the possibility of writing and erasing information, thus making the transistor behave as a single memory cell., This work was funded by ITN iSwitch 642196 (V.P. and M.S.M.), ERC StG 2012‐306826 e‐GAMES, the EuroNanoMed III project “AMI,” the Networking Research Center on Bioengineering, Biomaterials, and Nanomedicine (CIBER‐BBN), the Generalitat de Catalunya (2017‐SGR‐918) and the Spanish Ministry of Economy and Competitiveness, through the project FANCYCTQ2016‐80030‐R and “Severo Ochoa” Programme for Centers of Excellence in R&D (SEV‐2015‐0496). V.P. is enrolled in the Molecular and Regenerative Medicine Programme of the Università di Modena and Reggio Emilia. M.S.M. and Q.Z. are enrolled in the Materials Science PhD Program of Universitat Autònoma de Barcelona. S.C. acknowledges the People Programme (Marie Curie Actions) of the Seventh Framework Programme of the European Union (FP7/2007‐2013) under Research Executive Agency Grant Agreement No. 600388 (TECNIOSpring programme), and from the Agency for Business Competitiveness of the Government of Catalonia, ACCIÓ. Q.Z. acknowledges the China Scholarship Council, the National Natural Science Foundation (NSF) of China (11404266) and the Fundamental Research Funds for the Central Universities (Grant No. XDJK2011C041).

The objective of this paper is to characterize the atmospheric radiometeorological parameters (optical thickness and brightness temperature) at centimeter and millimeter waves. To this aim, we have exploited two radiative transfer models (RTMs): a three-dimensional model (3D-RTM), driven by numerical weather forecasts, and a stochastic one-dimensional (1-D) model (1D-RTM), fed by a synthetic clouds dataset. We have compared the radiative transfer simulations with measurements from two ground-based microwave radiometers: a profiler and a Sun-tracking radiometer. The peculiarity of the latter is the capacity of simultaneously measuring atmospheric optical thickness and brightness temperature in all-weather conditions and at variable elevation angles. The comparisons between simulations and measurements provide satisfactory results that assess the reliability of the 3D-RTM with some biases, in terms of brightness temperature, that should be investigated. 3D-RTM turns out to be able to successfully reproduce correlations between brightness temperature and optical thickness and correlations among the different frequency channels. This confirms the potential of the combined use of weather forecast models and physically-based RTMs. On the other hand, 1D-RTM reveals to be able to reproduce frequency-channel correlation trends, but additional climatological set-up are needed to make the model exploitable for the computation of statistics of atmospheric optical thickness. These comparisons also highlight some possible calibration errors in the Sun-tracking radiometer that must be fixed. Finally, we have exploited measurements from the Sun-tracking radiometer to develop a model to retrieve the probability of atmospheric optical thickness conditioned to a given elevation angle.

This paper aims at improving and assessing a previously developed technique to predict data volume transfer during deep-space satellite communication links at Ka - and ${X}$ -band (where the Earth’s atmosphere affects propagating signals). The proposed technique exploits a weather forecast (WF) model to predict the atmospheric state and a radiative transfer model to convert the atmospheric state into radiopropagation variables. The latter are used to design the link budget and to maximize transferred data-volume. This WF-based technique exploits the atmospheric attenuation as a random variable related to the statistic of the transmission error rate that drives the received data-volume and its uncertainty. The WF-based technique is evaluated for the test case of the BepiColombo mission to Mercury from ESA (European space agency) considering Cebreros and Malargue receiving ground-stations. Tuning and verification of the adopted models were accomplished exploiting ground-based meteorological measurements (weather stations, radiosoundings, and microwave radiometer) and simulating four years of data transmission. Results, in terms of yearly received data-volume and its uncertainty, highlight the advantages of short-term WF-based atmospheric statistics in opposition to the commonly used long-term climatological statistics. These advantages are evaluated at both Ka- and ${X}$ -band. The use of aggregated statistics derived from WF data is demonstrated as a reliable possibility of bypassing the lack of meteorological measurements.

Organic electrochemical transistors are fabricated on a poly(L-lactide-co-glycolide) substrate. Fast and sensitive performance of the transistors allows recording of the electrocardiogram. The result paves the way for new types of bioelectronic interfaces with reduced invasiveness due to bioresorption and soft mechanical properties. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

In this paper, we propose a measurement technique based on local strain measurements to perform real-time reconstruction of the overall structural deformation and the distributed stress field produced by the impact of a body on a water free surface. In particular, we seek establishing a measurement chain capable of acquiring and elaborating the signals at high frequency, so that it can be utilized to study rapidly varying strain fields, such as those occurring in impulsive events. Fiber Bragg gratings are utilized to sense the local structural deformation. Experiments are conducted on flexible plastic wedges with variable deadrise angles impacting on a quiescent fluid surface. The experimental tests are performed in free fall and we explore variations of the entry velocity by varying the drop height. The structural deformation is reconstructed from point-wise strain measurements utilizing a modal reconstruction methodology. The impact dynamics are analysed through accelerometers and linear position sensors. Results show that the impact behaviour of the flexible body is characterized by a main overall deformation where the structure is distorted in the direction of the loading, whereby marked vibrations, whose amplitude increase with the entry velocity, dominate the dynamic response. The influence of the mode shapes considered in the present analysis on the accuracy of the results is also observed. The proposed methodology allows for a fairly high acquisition frequency, which translates into a real-time structural reconstruction technique. Results show that the proposed methodology can be a valuable tool for the live monitoring of structures undergoing impact events.

A multilayer self-assembled monolayer (MuL-SAM) composed by i) cysteamine, ii) 4-formilphenyl boronic acid and iii) dopamine has been used to functionalize polycrystalline Au. Its electrochemical characterization shows how this surface engineering makes Au reactive toward dopamine. Kelvin probe measurements have shown how MuL-SAM tunes the surface potential of the bare Au. Such measurements are correlated with the electrical performances of organic field-effect transistors (OFETs), whose source/drain electrodes have been functionalized by MuL-SAM. Such devices, operated as charge-injection organic gauges (CIOGs), have shown sensitivity to the concentration of dopamine in the range of [1, 50] nM.

The amorphous aggregation of A?1-40 peptide is addressed by using micromolding in capillaries. Both the morphology and the size of the aggregates are modulated by changing the contact angle of the sub-micrometric channel walls. Upon decreasing the hydrophilicity of the channels, the aggregates change their morphology from small aligned drops to discontinuous lines, thereby keeping their amorphous structure. A?1-40 fibrils are observed at high contact angles.

The small ungauged basins of the highly urbanized area of the city of Rome are often the subject of critical flood conditions for the significant human-made transformations. In this work the EBA4SUB framework, implementing the hydrogeomorphic width function instantaneous unit hydrograph rainfall run-off model, and using digital elevation model, land use and synthetic precipitation as main input information, is applied for evaluating extreme hydrologic forcing conditions at the basic scale. The goal is to understand the rationale behind the observed increasing frequency of local urban inundations that are also observed in the uplands. Results present the impact of urbanization expressed by both the run-off coefficient, the artificial drainage, impacted by paved surfaces and a dramatic number of river–road intersections (i.e. culverts), and the upstream to downstream non-natural scaling behaviour of hydrologic parameters and in particular the peak discharge per unit drainage area.

We describe a potentiometric sensor based on Electrolyte-Gated Organic Field-Effect Transistor (EGOFET) for "in vitro'' detection of dopamine. The sensing element of this device resides at the Au gate-aqueous solution interface by means of a self-assembled monolayer (SAM) composed by cysteamine and 4-formylphenyl boronic acid. The covalent and selective adsorption of dopamine induces a surface dipole potential which shifts the electrode work function and modulates the double layer capacitance. As a result, our device is capable to detect dopamine up to pico-molar concentration showing higher sensitivity with respect to other approaches. For this reason the interface engineering of our EGOFET gate is a promising route for diagnostic applications. (c) 2012 Elsevier B.V. All rights reserved.

A multiscale investigation of N,N-bis(n-octyl)-x:y, dicyanoperylene-3,4:9,10- bis(dicarboximide), PDI8-CN2, shows the same molecular arrangement in the bulk and in thin films sublimated on SiO2/Si wafers. Non-conventional powder diffraction methods and theoretical calculations concur to provide a coherent picture of the crystalline structure. X-ray diffraction (XRD) and atomic force microscopy (AFM) analyses of films of different thickness depos- ited at different substrate temperatures indicate the existence of two temper- ature-dependent deposition regimes: a low-temperature (room temperature) regime and a high-temperature (80­120 °C) one, each characterized by dif- ferent growth mechanisms. These mechanisms eventually result in different morphological and structural features of the films, which appear to be highly correlated with the trend of the electrical parameters that are measured in PDI8-CN2-based field-effect transistors.

Guest editors Paolo Samorì and Fabio Biscarini introduce the Nanomaterials properties tuned by their environment themed issue of Chemical Society Reviews.

The quantification of urea is of the utmost importance not only in medical diagnosis, where it serves as a potential indicator of kidney and liver disfunction, but also in food safety and environme ...

A novel fully organic bioelectronic device is presented and validated as electronic transducer and current stimulator for brain implants. The device integrates polymeric electrodes made of poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) on paper thin foils, resulting in a high surface-to-volume ratio architecture that exhibits high sensitivity to interfacial ionic transport phenomena. The prototyping technique herein presented yields devices for the bidirectional communication with biological systems whose dimensionality can be controlled according to the desired application. Transduction of ultra-low local-field potentials and delivery of voltage pulse-trains alike those used in deep-brain stimulation are herein assessed, paving the way towards novel theranostic strategies for the treatment of Parkinson’s Disease and other severe neurodegenerative and/or traumatic pathologies of the central nervous system.

Conducting polymer electrodes based on poly (3, 4 ethylenedioxythiophene): polystyrene sulfonate were used to record electrophysiological signals from autonomous cardiac contractile cells present in embryoid bodies. Signal detection was carried out by measuring the displacement current across the polymer/electrolyte double-layer capacitance, and compared with voltage detection. While for relatively low capacitance electrodes, the voltage amplification provides higher signal quality, and for high capacitive electrodes, the displacement current method exhibits a higher signal-to-noise ratio. It is proposed that the displacement current method combined with high capacitive polymer-based electrodes is adequate to measure clusters of cells and whole organs. Our approach has a great potential in fundamental studies of drug discovery and safety pharmacology. Portuguese Foundation for Science and Technology through the Implantable Organic Devices for Advanced Therapies Project [PTDC/EEI-AUT/5442/2014] Instituto de Telecomunicacoes [UID/Multi/04326/2013] info:eu-repo/semantics/publishedVersion

none 14 si Biorecognition is a central event in biological processes in the living systems that is also widely exploited in technological and health applications. We demonstrate that the Electrolyte Gated Organic Field Effect Transistor (EGOFET) is an ultrasensitive and specific device that allows us to quantitatively assess the thermodynamics of biomolecular recognition between a human antibody and its antigen, namely, the inflammatory cytokine TNFα at the solid/liquid interface. The EGOFET biosensor exhibits a superexponential response at TNFα concentration below 1 nM with a minimum detection level of 100 pM. The sensitivity of the device depends on the analyte concentration, reaching a maximum in the range of clinically relevant TNFα concentrations when the EGOFET is operated in the subthreshold regime. At concentrations greater than 1 nM the response scales linearly with the concentration. The sensitivity and the dynamic range are both modulated by the gate voltage. These results are explained by establishing the correlation between the sensitivity and the density of states (DOS) of the organic semiconductor. Then, the superexponential response arises from the energy-dependence of the tail of the DOS of the HOMO level. From the gate voltage-dependent response, we extract the binding constant, as well as the changes of the surface charge and the effective capacitance accompanying biorecognition at the electrode surface. Finally, we demonstrate the detection of TNFα in human-plasma derived samples as an example for point-of-care application. Berto, Marcello; Casalini, Stefano; Di Lauro, Michele; Marasso, Simone L; Cocuzza, Matteo; Perrone, Denis; Pinti, Marcello; Cossarizza, Andrea; Pirri, Candido F; Simon, Daniel T; Berggren, Magnus; Zerbetto, Francesco; Bortolotti, Carlo A; Biscarini, Fabio Berto, Marcello; Casalini, Stefano; Di Lauro, Michele; Marasso, Simone L; Cocuzza, Matteo; Perrone, Denis; Pinti, Marcello; Cossarizza, Andrea; Pirri, Candido F; Simon, Daniel T; Berggren, Magnus; Zerbetto, Francesco; Bortolotti, Carlo A; Biscarini, Fabio

Electrolyte-gated organic field-effect transistors (EGOFETs), based on ultrathin pentacene films on quartz, were operated with electrolyte solutions whose pH was systematically changed. Transistor parameters exhibit nonmonotonic variation versus pH, which cannot be accounted for by capacitive coupling through the Debye–Helmholtz layer. The data were fitted with an analytical model of the accumulated charge in the EGOFET, where Langmuir adsorption was introduced to describe the pH-dependent charge buildup at the quartz surface. The model provides an excellent fit to the threshold voltage and transfer characteristics as a function of the pH, which demonstrates that quartz acts as a second gate controlled by pH and is mostly effective from neutral to alkaline pH. The effective capacitance of the device is always greater than the capacitance of the electrolyte, thus highlighting the role of the substrate as an important active element for amplification of the transistor response.

In this paper we present a computational model for the fluid structure interaction of a buoyant rigid body immersed in a free surface flow. The presence of a free surface and its interaction with buoyant bodies make the problem very challenging. In fact, with light (compared to the fluid) or very flexible structures, fluid forces generate large displacements or accelerations of the solid and this enhances the artificial added mass effect. Such a problem is relevant in particular in naval and ocean engineering and for wave energy harvesting, where a correct prediction of the hydrodynamic loading exerted by the fluid on buoyant structures is crucial. To this aim, we develop and validate a tightly coupled algorithm that is able to deal with large structural displacement and impulsive acceleration typical, for instance, of water entry problems. The free surface flow is modeled through the volume of fluid model, the finite volume method is utilized is to discretize the flow and solid motion is described by the Newton-Euler equations. Fluid structure interaction is modeled through a Dirichlet-Newmann partitioned approach and tight coupling is achieved by utilizing a fixed-point iterative procedure. As most experimental data available in literature are limited to the first instants after the water impact, for larger hydrodynamic forces, we specifically designed a set of dedicated experiments on the water impact of a buoyant cylinder, to validate the proposed methodology in a more general framework. Finally, to demonstrate that the proposed numerical model could be used for a wide range of engineering problems related to FSI in multiphase flows, we tested the proposed numerical model for the simulation of a floating body.