0000000001032789
AUTHOR
A. Tomasino
Terahertz four-wire waveguides for broadband signal processing and multiplexing
In this work, we introduce a versatile metal-wire waveguide geometry, namely a four-wire waveguide, which is capable of sustaining two independent and orthogonally polarized fundamental modes, thus acting as a broadband polarization-division multiplexer. By integrating multiscale-structured grooves into the wires of such a waveguide, we demonstrate the independent manipulation of polarization-division terahertz signals.
Design and Fabrication of Terahertz Metallic Gratings on a Two-Wire Waveguide
In this study, we present the design, fabrication and experimental characterization of waveguide-integrated gratings operating at THz frequencies
Design and realization of a portable continuous wave fNIRS
A design and implementation of a portable functional Near InfraRed Spectroscopy embedded system prototype is described. In this theoretical and experimental work, we present an embedded system hosting 64 LED sources and 128 Silicon PhotoMultiplier detectors (SiPM). The elementary part of the structure is a flexible probe “leaf” consisting of 16 SiPMs, 4 couples of LEDs, each operating at two wavelengths, and a temperature sensor. The hardware system is based on an ARM main microcontroller that allows to perform both the switching time of LEDs and the acquisition of the SiPM outputs. The performed preliminary experimental tests achieved very promising results, thus demonstrating the effectiv…
Terahertz time-domain spectroscopy based on photoconductive antennas
In this work, we present our first experimental results obtained by means of a THz-TDS setup based on photoconductive antennas (PCAs). The main elements of the setup are: i) a mode-locked Ti:Sapphire femtosecond laser (Mai-Tai SP - Spectra Physics), providing optical pulses at 800±20 nm with a duration < 50 fs and repetition rate of 84 MHz; ii) two photoconductive antennas, made in LT-GaAs (Low-Grown Temperature Gallium Arsenide), operating as THz emitter and detector; iii) an optical delay line.
Spontaneous Endoreduplication, Tetraploidy and Chromosome Breakage in Lymphocyte Cultures from Healthy Subjects
SUMMARY42,703 metaphases of peripheral lymphocytes from 20 healthy subjects (10 women and 10 men) were examined in order to establish the frequency of endoreduplicated cells and of tetraploid cells without diplochromosomes. Frequencies were found to be 0.016% and 0.112%, respectively. The two sexes did not differ as to the frequency of tetraploid cells, with and without diplochromosomes (about 0.13% in either sex). In a total of 2,135 well spread metaphases examined, 26 cells (i.e. 1.2%) with chromosomal breaks were found. Again, no significant differences between the two sexes were found as to such chromosome abnormalities.
Terahertz polarization-division multiplexing within a four-wire waveguide
We demonstrate a new metal-wire waveguide topology, namely a four-wire waveguide, which simultaneously acts as a broadband terahertz polarization-division multiplexer and as a novel platform to realize the independent manipulation of polarization-division multiplexed terahertz signals.