746 research outputs found
RF transversal filter using an AOTF
An acoustooptic tunable filter (AOTF) is employed in an optical system to obtain an independently tunable and reconfigurable radio-frequency transversal filter. Manipulating only the control signals of the AOTF modifies the transfer function of the filter. This letter demonstrates the experimental implementation of a two-tap version of the proposed filter. Avenues for increasing the number of taps are discussed
Weyl holographic superconductor in the Lifshitz black hole background
We investigate analytically the properties of the Weyl holographic
superconductor in the Lifshitz black hole background. We find that the critical
temperature of the Weyl superconductor decreases with increasing Lifshitz
dynamical exponent, , indicating that condensation becomes difficult. In
addition, it is found that the critical temperature and condensation operator
could be affected by applying the Weyl coupling, . Moreover, we compute
the critical magnetic field and investigate its dependence on the parameters
and . Finally, we show numerically that the Weyl coupling parameter
and the Lifshitz dynamical exponent together control the size and
strength of the conductivity peak and the ratio of gap frequency over critical
temperature .Comment: 25 pages, 22 figure
Role of Mas receptor antagonist (A779) in renal hemodynamics in condition of blocked angiotensin II receptors in rats
The vasodilatory effect of angiotensin 1–7 (Ang 1-7) is exerted in the vascular bed via Mas receptor (MasR) gender dependently. However, the crosstalk between MasR and angiotensin II (Ang II) types 1 and 2 receptors (AT1R and AT2R) may change some actions of Ang 1-7 in renal circulation. In this study by blocking AT1R and AT2R, the role of MasR in kidney hemodynamics was described. In anaesthetized male and female Wistar rats, the effects of saline as vehicle and MasR blockade (A779) were tested on mean arterial pressure (MAP), renal perfusion pressure (RPP), renal blood flow (RBF), and renal vascular resistance (RVR) when both AT1R and AT2R were blocked by losartan and PD123319, respectively. In male rats, when AT1R and AT2R were blocked, there was a tendency for the increase in RBF/wet kidney tissue weight (RBF/KW) to be elevated by A779 as compared with the vehicle (P=0.08), and this was not the case in female rats. The impact of MasR on renal hemodynamics appears not to be sexual dimorphism either when Ang II receptors were blocked. It seems that co-blockade of all AT1R, AT2R, and MasR may alter RBF/ KW in male more than in female rats. These findings support a crosstalk between MasR and Ang II receptors in renal circulation
A novel RF photonics band-pass filter
A novel photonically implemented RF band-pass filter, using a comb-laser and a fiber dispersive medium is presented. Positive and negative taps are achieved by driving two Mach-Zehnder modulators with opposing quadrature biases
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