This study compared pure-tone threshold data, acoustic reflex threshold data, and loudness growth data for a group of 25 hyperacusic male subjects vs. a group of 13 nonhyperacusic male subjects. Pure-tone thresholds and acoustic reflex thresholds were obtained in 5-dB steps, using revised HughsonWestlake procedures. Loudness growth functions were obtained with a fractionation (method of adjustm...

This paper proposes vector modulator for changing the phase of a signal in passive beamforming system. Vector modulator is used to perform a phase shift function with added benefit of amplitude control. It is used to improve the directivity of RF waves in Wireless systems. Vector modulator is implemented for a center frequency of 902.5 MHz. The simulation is performed for individual blocks of t...

This work presents a monolithic DC~4GHz 6-bit digital attenuator with low insertion phase shift and attenuation error. Based on GaAs E/D pHEMT process, a serial-to-parallel converter is introduced to decrease the control pads of the chip. In the 16dB attenuation bit, a switched-path-type topology is employed in order to extend the bandwidth and achieve low insertion phase shift. The attenuator ...

It is not uncommon to use profiles to act as energy absorption parts in vehicle safety systems. This work analyses an impact attenuator based on a simple design and discusses the use of a thermoplastic material. We present the design of the impact attenuator and a mechanical test for the prototype. We develop a simulation model using the finite element method and explicit dynamics, and we evalu...

The pyrBI operon of Escherichia coli K-12 encodes the subunits of the pyrimidine biosynthetic enzyme aspartate transcarbamylase (carbamoylphosphate:L-aspartate carbamoyltransferase, EC 2.1.3.2). Expression of this operon apparently is negatively regulated by the intracellular levels of UTP. To elucidate the regulatory mechanism in which UTP functions, the nucleotide sequence of the promoter-reg...

A 5-fluorotryptophan-resistant mutant, termed 1041, was isolated from Brevibacterium lactofermentum AJ12036. The anthranilate synthase of 1041 was insensitive to feedback inhibition by tryptophan, and the specific activities of the anthranilate synthase and anthranilate phosphoribosyltransferase of 1041 were 29- and 23-fold higher than those in parental strain AJ12036, respectively. A single-ba...

The possibility of increasing the apertures of the LCLS gas attenuator/gas detector system is considered. It is shown that increase of the apertures from 3 to 6 mm, together with 4fold reduction of the operation pressure does not adversely affect the vacuum conditions upstream or downstream. No change of the pump speed and the lengths of the differential pumping cells is required. One minor mod...