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According to the recent studies on the psychophysiology of touch, a haptic effector designed in a neuromorphic way was projected, designing an electronic card as to be able to deliver variable signals over time and in intensity. The two-dimensional arrays of micro-actuators were made either with planar geometry or with three-dimensional, semi-spherical or “dome” geometry. Subsequently, on both the behavioral and the electrophysiological level the haptic sensation received by the effector was evaluated on 6 subjects and compared to real stimulations of different grains (Paper). During the various stimulations the subject was in a state of Resting State (RS). Each stimulation had a frequency range ranging from 2 to 500 Hz on 2 and 5 s. Analysis of behavioral responses and the alpha rhythm in RS showed significant differences for low frequencies vs Paper. RS highlighted differences in ROIs on the various frequency distributions, especially low frequencies in Frontal ROI. This pilot study indicates that the best frequencies for a haptic simulation are between a range from 20 Hz to 166 Hz.

The efficient internalization of TGF-beta inhibitor-loaded polyelectrolyte capsules and particles is studied in two HCC cell lines. Two polyelectrolyte pairs (biocompatible but not degradable and biodegradable crosslinked with gluteraldehyde) are employed for coating. The capsules are characterized by SEM. LY is successfully loaded inside the core and embedded between polymer layers. MS is used to quantify the loading efficiency by comparing post-loading and core-loading methods, since both coated templates and hollow shells are used as carriers. CLSM confirms dissolution of the pre-formed multilayer upon enzymatic degradation as the method of release, and migration assays demonstrate a higher inhibition efficiency of TGF-beta in tailored biodegradable capsules compared to free LY administration.

We investigated the optical phonon excitations of laterally aligned nanorod arrays by resonant Raman scattering. We observed a strong suppression of the surface-optical phonon modes in the closely packed aligned arrays and a small asymmetry in the longitudinal-optical phonon peak with respect to the rod alignment orientation. These observations can be explained by the spatial distribution of the potential of the different phonon modes derived from the first principles calculations.

As modern electronics rapidly approach the ultimate level of integration (typically thought to be at the nanoscale level), the fascinating world of biomolecules provides new opportunities and directions for further miniaturization. In this work we review our results in the field of biomolecular electronics, starting from the fabrication of nanojunctions up to the implementation, of hybrid devices.

The efficient internalization of TGF-beta inhibitor-loaded polyelectrolyte capsules and particles is studied in two HCC cell lines. Two polyelectrolyte pairs (biocompatible but not degradable and biodegradable crosslinked with gluteraldehyde) are employed for coating. The capsules are characterized by SEM. LY is successfully loaded inside the core and embedded between polymer layers. MS is used to quantify the loading efficiency by comparing post-loading and core-loading methods, since both coated templates and hollow shells are used as carriers. CLSM confirms dissolution of the pre-formed multilayer upon enzymatic degradation as the method of release, and migration assays demonstrate a higher inhibition efficiency of TGF-beta in tailored biodegradable capsules compared to free LY administration.

The internalisation efficiency and cytotoxicity of polymeric microparticles and capsules were studied for three different adherent cell lines: HeLa (human cervice cancer), MCF-7 (human breast cancer) and B104 (murine neuroblastoma). Microparticles of colloidal CaCO3 cores coated with either layerby- layer self-assembled oppositely charged biosynthetic (PSS\PAH) or biodegradable (DXS\PRM) polyelectrolytes and hollow capsules thereof, obtained upon removal of the CaCO3 cores by EDTA, were fabricated. Fluorescent-labeled polymer layers coated onto CaCO3 cores were employed for evaluating cell uptake efficiency. Confocal laser scanning microscopy was used to confirm dissolution of preformed biodegradable multilayers. Cellular viability for all type of colloidal entities was preserved, indicating safety and tolerability of the potential drug carriers.

The self-assembly of polypeptides into stable, conductive, and intrinsically fluorescent biomolecular nanowires is reported. We have studied the morphology and electrical conduction of fibrils made of an elastin-related polypeptide, poly(ValGlyGlyLeuGly). These amyloid-like nanofibrils, with a diameter ranging from 20 to 250 nm, result from self-assembly in aqueous solution at neutral pH. Their morphological properties and conductivity have been investigated by atomic force microscopy, scanning tunneling microscopy, and two-terminal transport experiments at the micro- and nanoscales. We demonstrate that the nanofibrils can sustain significant electrical conduction in the solid state at ambient conditions and have remarkable stability. We also show intrinsic blue-green fluorescence of the nanofibrils by confocal microscopy analyses. These results indicate that direct (label-free) excitation can be used to investigate the aggregation state or the polymorphism of amyloid-like fibrils (and possibly of other proteinaceous material) and open up interesting perspectives for the use of peptide-based nanowire structures, with tunable physical and chemical properties, for a wide range of nanobiotechnological and bioelectronic applications.

We demonstrate a method for the simultaneous fabrication (without the need of expensive e-beam systems) of large arrays of nanodevices working at room temperature. The electrode gap is defined by a selective wet-etching of a AlGaAs/GaAs quantum well structure and controlled with nanometer precision. A selective oxidation of the Al rich barrier reduces the bulk leakage current by six orders of magnitude and extends the applicability of the produced devices to room temperature functionality. As a demonstration, we employ here these nancjunctions to investigate transport in molecular tunnel-junctions based on individual Azurins, a blue copper protein, under ambient conditions. This approach opens the way to the fabrication of complex circuits consisting of different nanodevices. (c) 2007 Elsevier B.V. All rights reserved.

We carried out an electron-beam lithography study of the sub-µm performances of Langmuir-Blodgett films of Polycyanoacrylates fabricated by the Langmuir-Schaefer technique. We tested the sensitivity of films made by 48 monolayers, finding a dose of less than 1 µC/cm2, and employed them as masks for wet etching of Cr metal layers, with resolutions up to 100 nm. These results suggest that the modified Langmuir-Schaefer technique, and the Polycyanoacrylate-based resists, are very promising for nanotechnology applications.

An economical nanoarray method to electrically detect hybridization events is demonstrated. As a proof of concept, we fabricated a sensor for DNA sequencing, in which targets are oligonucleotides conjugated to gold nanoparticles. As a consequence of target–probe binding events, a conductive bridge forms between two electrodes, resulting in a quantized change in conductivity. This enables a robust detection of a few (down to single) hybridization events and can be potentially applied also to other binding events (like specific interactions between proteins, antibodies, ligands and receptors). Moreover, target amplification techniques (such as PCR) are no longer necessary.

A preliminary study to define suitable optical terminals for intersatellite links is presented, and the main configuration tradeoffs are discussed. A modular design approach was pursued, and some innovative technology solutions were traded in order to satisfy the basic requirement of a limited terminal mass. A high-capacity (500 Mbps) return link channel is feasible and fast, and accurate acquisition and tracking operation are achieved.

GEO and LEO terminals for optical Interorbit Links (IOL), based on diode—pumped Nd:Host laser technology, are under definition. Assuming a future european scenario with a few LEO users candidate for laser communications, our design choice is oriented towards a compact and lightweight LEO terminal and a GEO one capable of relaying in single—access mode also other channels, implemented at different wavelengths. System and design issues relevant to the overall terminal and the Communication, PAT (Pointing, Acquisition and Tracking) and Optics subsystems are presented. The ternIinal configurations are shown with respect to their possible layout and to their impact on the host spacecraft in terms of mass and power consumption.

A laser communication system concept for intersatellite link applications, based on diode-pumped Nd laser technology and coherent detection, is analyzed. As a result of modulation format comparison, parametric link budget and trade-off analysis, a DPSK heterodyne receiver-based communication system is proposed. The coherent-detection full duplex 1.064-1.047-micron Nd-laser link offers the advantages of high link capacity and quality, reduced telescope aperture and relaxed pointing accuracy requirements.© (1990) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.