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A modification and addition to the prior art type of multiple driver push-pull loudspeaker system for subwoofer, bass, or lower midrange frequencies, which prior system is able to reduce the even-order push-pull out-of-phase driver-produced 2nd, 4th, etc. distortion harmonics by the order of 15 to 25 dB in the radiated sound waves. The present invention reduces the important remaining in-phase distortion harmonics using outputs of sensors mounted on the voice coils of each driver to generate electrical signals which are processed and used to substantially lower the remaining in-phase distortion with feedback through a single signal amplifier chain. The present invention contributes from 15 to 30 dB of in-phase distortion reduction of odd-order harmonics and, at relatively high sound power levels only, also reduces some in-phase, relatively lower level, even-order distortion. In addition, separate electrical outputs processed from sensor motion can provide pure even-order harmonics in real time, which outputs can be made available for other possible uses. Obviously, the relatively pure odd-order harmonics normally fed to a mixer in the signal amplifier chain could also be used as a separate output if desired.

A study is made of the characteristics of wavefront reversal in a resonantly amplifying medium. The region of the effective interaction between waves is of finite size and the phase relationships between the constant and alternating components of the resultant signal influence the signal increment.

This paper describes the optimization of a lateral magnetotransistor (LMT), combined with a signal amplifier. The base width, the position of the base contact and the substrate doping level are important design criteria. An integrated circuit comprising a dual-collector lateral magnetotransistor and a differential amplifier yields a sensitivity of 10 V/T.

Frequency and transient response equations for the current-transfer ratios of the double-base diode are calculated from theory and checked experimentally. To obtain these results, the device is operated as a small signal amplifier in the negative-resistance region and the frequency response characteristics thus obtained are used to predict the device behavior. The effects of carrier recombination and electric field upon the response characteristics are evaluated and experimental results are presented.

The production and use of a simple electronic amplification system (incorporating an automatic arming facility) for use in shock-speed timing in conjunction with a thin film shock-sensor in a shock tunnel located in an electrically noisy environment is described.

Summary Newly synthesized membrane proteins are queried by ubiquitin ligase complexes and triaged between degradative and nondegradative fates. The mechanisms that convert modest differences in substrate-ligase interactions into decisive outcomes of ubiquitination are not well understood. Here, we reconstitute membrane protein recognition and ubiquitination in liposomes using purified components from a viral-mediated degradation pathway. We find that substrate-ligase interactions in the membrane directly influence processivity of ubiquitin attachment to modulate polyubiquitination. Unexpectedly, differential processivity alone could not explain the differential fates in cultured cells of degraded and nondegraded clients. Both computational and experimental analyses identified continuous deubiquitination as a prerequisite for maximal substrate discrimination. Deubiquitinases reduce polyubiquitin dwell times preferentially on clients that dissociate more rapidly from the ligase. This explains how small differences in substrate-ligase interaction can be amplified into larger differences in net degradation. These results provide a conceptual framework for substrate discrimination during membrane protein quality control., Graphical Abstract, Highlights • Membrane protein ubiquitination has been reconstituted with purified factors in vitro • Differential ligase interactions alone cannot explain how clients are discriminated • Maximal client discrimination requires competing deubiquitination activity • Deubiquitinases control the dwell time of a degradation mark on potential clients, Optimal substrate discrimination by the protein degradation machinery requires deubiquitinases (DUBs) to counteract E3 ligases to exaggerate the differential polyubiquitination among potential clients. DUBs have greater access to well-folded substrates that show weaker interactions with the ligase, protecting them from degradation.

Current interest in efficient blue solid-state laser sources has led to research aimed at converting laser radiation in the 1.3μ region to the blue (4300–4600A). In this paper we describe laser operation on the \(^4{{\text{F}}_{3/2}}{ - ^4}{{\text{I}}_{13/2}}\) laser transition in Nd:YLF including the prominent π and σ polarized lines, 1.321μ and 1.313μ, and continuous tuning over the weaker band between 1.362 and 1.37 microns. Small signal amplifier gain measurements of the various transitions between these multiplets are presented in addition to a Q-switched oscillator, emitting 90mJ at 1.3665μ and an oscillator amplifier chain emitting 0.5J at 1.313 microns.

An investigation was made of the use of a two-pass telescopic neodymium-glass amplifier in combination with a Brillouin mirror in high-gain wavefront-reversal systems. Small-signal gain of 107 was achieved for a single pulse of SO nsec duration and no self-focusing filaments were observed in the output stage when the energy was up to 100 J.