TIME-DOMAIN ULTRA-WIDE BAND MICROWAVE MEASUREMENT TECHNIQUES FOR MINIATURIZED DIELECTRIC SPECTROSCOPY AND CHIPLESS RFID SYSTEMS

Dielectric spectroscopy is a versatile experimental technique for identifying materials based on their electrical properties. Dielectric spectroscopy measures complex relative permittivity of materials as a function of frequency. Time-domain dielectric spectroscopy is a fast, simultaneous, and highly accurate technique for unique detection and characterization of materials over broad frequency ranges. In time-domain technique, the complete characterization of material is rapidly obtained by using a short-duration excitation pulse that simultaneously contains all the desired frequencies. In this dissertation, three miniaturized time-domain dielectric spectroscopy systems are presented for material sensing in ultra-wide band frequency range. The first system is a contactless spectroscopy system based on using a pair of Vivaldi antennas located in the near-field region for sensing liquid materials. The response of this sensing unit is measured in a combined timefrequency- domain system as well as a pure time-domain system. The second system is a miniaturized contact-based spectroscopy system that uses planar wide band sensors with a few L amount of test material for sensing in a wide dynamic range. The contact-based sensor is initially designed for phase measurement and in an extended version for phase and magnitude measurement of material responses. The third system is based on dual-comb spectroscopy technique. In dual-comb spectroscopy, the microwave properties of test material is mapped to the baseband frequency that significantly reduces the receiver complexity. The implementation and experimental results of the above-mentioned time-domain spectroscopy systems are reported. In addition, a high capacity chipless RFID tag for identification is presented in this dissertation. Chipless RFID tags are passive and printable structures with unique electromagnetic signatures that are considered as substitutes for traditional barcodes and as alternatives to chipped RFID tags. Moreover, three chipless RFID readers in time-domain including IR-UWB, chirped pulsed Fourier transform microwave, and dual-comb technique are demonstrated for identifying the chipless RFID tag

Co-administration of the low dose of orexin and nitrergic antagonists induces an antidepressant-like effect in mice

It is now well-established that orexins (OXs) and their receptors are involved in the pathophysiology of depression. Considering the evidence indicating the importance of nitric oxide (NO) system in the mood modulation, this study investigated the effect of intraperitoneal (i.p.) administration of orexin 1 (OX1) receptor antagonist -SB334867- alone or in combination with NO agents on depression using the forced swimming test (FST), tail suspension test (TST) and the number of crossings in open-field test (OFT) in mice. Our results indicated that administration of SB334867 at the dose of 0.5 mg/kg decreased the immobility time in the FST without effect on locomotor activity, suggesting an antidepressant-like effect of SB334867. Moreover, L-Arginine (a NO precursor; 750 mg/kg) or L-NAME (a non-selective nitric oxide synthase (NOS) inhibitor, 10 mg/kg) administration by itself decreased the immobility time in the FST. Interestingly, co-administration of a sub-threshold dose of L-NAME, but not L-Arginine, in combination with an ineffective dose of SB334867 produced an antidepressant-like effect in the FST and TST. It should be noted, none of the drugs elicited significant effects on the locomotor activity in the OFT. Altogether, the present data propose that a combination of the sub-effective dose of OX and NO antagonists can be evaluated as an option for the clinical treatment of depression in humans. © 2018 Elsevier Masson SA