background: noise-induced hearing loss (nihl) is a common, irreversible occupational disease. statins have recently been proposed to prevent nihl. objective: to assess the effect of atorvastatin for the prevention of nihl in rats. methods: in this experimental study, forty 2–3-month-old wistar male rats were divided into 5 groups of 8 animals. 3 groups of rats received atorvastatin at doses of ...

We implemented a laser system to be used in an optical transduction chain for the gravitational-wave bar detector AURIGA (Antenna Ultracriogenica Risonante per l'Indagine Gravitazionale Astronomica; Ultracryogenic Resonant Antenna for Astronomical Gravitational Investigation). This system is based on a Nd:YAG laser and includes quantum-limited power stabilization in the acoustic range, deep pha...

Orthogonal Frequency Division Multiplexing (OFDM) is a method of encoding digital data on multiple carrier frequencies. OFDM has developed into a popular scheme for wide-band digital communication. Despite its advantages, it has a major drawback of its high Peak-to-Average Power Ratio (PAPR) value which degrades its efficiency and increases its cost. In this paper, two proposed systems are disc...

A simple non-linear network for amplitude stabilization in harmonic quadrature oscillator (QO) is analyzed. The oscillation startup conditions for QO topology with two operational amplifiers are used for amplitude adjustment by element values. A closed form expression for the amplitude setting resistance is derived. Total harmonic distortion (THD) is expressed as closed form function of the est...

The MACHO variables of LMC Field 77 that lie in the vicinity of the Cepheid instability strip are reexamined. Among the 144 variables that we identify as Cepheids we find 14 that have Fourier amplitudes < 0.05 mag in the MACHO red band, of which 7 have an amplitude < 0.006mag : we dub the latter group of stars ultra-low amplitude (ULA) Cepheids. The variability of these objects is verified by a...

A previous analysis of the mechanical behavior of current ballistocardiographic systems allowed the prediction of certain relationships between records from the Starr high-frequency bed and those representing undistorted forces applied to the body by the cardiovascular "generator." The latter were obtained by recording the acceleration of an "aperiodic mercury bed" platform. A relationship betw...

This paper presents a low-frequency amplitude modulator and demodulator based on Field Programmable Analogue Array (FPAA) devices. For creating the FPAA circuits, amplitude modulation and synchronous demodulation methods known from designing analogue RF transmission systems have been adapted. The proposed system allows redesigning the analogue conditioning stage thanks to the use of a FPAA devi...

Amplitude modulation systems are used in many areas of engineering, especially communication based disciplines. Typical systems have low-level signals which encode the desired information to be transmitted. These low-level signals are usually not of adequate power to transmit the desired information across a target medium, thus requiring modulation and power amplification. In general, two goals...