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Introduction: Although the Baha 5SP has been commercially available for six years, very few studies have been performed on the device's efficacy. The current study aims to evaluate the characteristics and audiological results in patients with severe‐to‐profound mixed hearing loss fitted with this superpower sound processor. Methods: This retrospective evaluation was conducted at a tertiary referral centre where a series of 82 adult patients with severe‐to‐profound mixed hearing loss were implanted with a percutaneous bone‐anchored hearing system and fitted with a superpower sound processor between 2016 and 2019. Patients with incomplete or unreliable audiological data (n = 24) were excluded, resulting in 58 data sets for analysis. The main outcome measures were unaided and aided pure‐tone thresholds and aided free‐field speech perception in quiet. Results: The median unaided air conduction (AC) threshold averaged across 0.5, 1 and 2 kHz (PTA0.5–2kHz) of all patients was 75 dB hearing loss (HL); the median unaided AC averaged across 1, 2 and 4 kHz (PTA1–4kHz) was 84 dB HL. For bone conduction and direct bone conduction, the median PTA0.5–2kHz was 52 and 47 dB HL, respectively. With the superpower device, the median free‐field speech reception threshold was 54 dB sound pressure level (SPL), and the median speech perception score at 65 dB SPL was 80%. Conclusions: At least 75% of the patients reached a maximum phoneme score of 70%. For patients with lower scores, the superpower device still provides a substantial hearing benefit. This makes the superpower device particularly suitable for patients with severe‐to‐profound mixed hearing loss with a contraindication for conventional hearing aids and/or cochlear implants. [ABSTRACT FROM AUTHOR]

This brief focuses on the robustness of the ring amplifier (RA), an alternative to the operational transconductance amplifier (OTA) in the deep nanoscale CMOS process. The effective gain (EG) of the RA shows diverse characteristics from the DC gain and can be treated as a non-linear gain error (NLGE). The EG shows a notable variation when taking process, supply voltage, and temperature (PVT) into consideration. An improved statistical calibration based on the back-end stage data is proposed to compensate the NLGE. A prototype SAR-assisted pipeline ADC with a quick-start RA is implemented in a 28-nm CMOS process, achieving 60.3 dB SNDR and 76.5 dB SFDR with a 6 MHz input at 625 MS/s. The SNDR and SFDR are 58.6 dB and 70.7 dB with a Nyquist input frequency and consumes 13.2 mW, achieving Walden and Schreier figure-of-merit (FoM) values of 30.4 fJ/conv.-step and 162.2 dB. For a −6 dBFS 50 MHz input, the measured SNDR and SFDR are above 55.5 dB and 68.9 dB with supply voltage and temperature fluctuation. [ABSTRACT FROM AUTHOR]

Abstract A quadruple GEM detector has been assembled in a standalone configuration and operated using Ar and CO 2 gas mixtures in proportions of 70:30 and 90:10. Detailed performance study of the detector has been made by using 106Ru-Rh β -source and X-ray spectrum of 55Fe source. Results of these measurements are presented in terms of gain, efficiency, energy and time resolutions and also compared with our earlier triple GEM results. The energy resolution has been found to be somewhat worse compared with that of the triple-GEM detector. Effect of drift field on electron transparency and time resolution has been studied in detail. [ABSTRACT FROM AUTHOR]

A quadruple GEM detector has been assembled and operated using Ar/CO 2 90:10 and 70:30 gas mixtures. Detailed study of the effective gain and energy resolution of the detector are performed using the X-ray spectrum of 55Fe source. The gain and energy resolution of the detector are measured and compared for two different electric field configurations, the standard field setting and the ion backflow (IBF) field setting. It is observed that for the standard field configuration the quadruple GEM detector can operate at lower operating voltages and has better energy resolution compared to IBF field setting. [ABSTRACT FROM AUTHOR]

X-ray absorption spectroscopy at sub-keV energies dictates the use of detectors that can attain a good signal-to-noise ratio. We report a recent study undertaken at Science and Technology Facilities Council, Daresbury Laboratory to evaluate the performance of a Gas Electron Multiplier (GEM) for this purpose. The main impetus of this study was to investigate the relevant parameters such as the effective gain and energy resolution in the X-ray energy range of 270-930 eV. This study demonstrated that a single stage GEM can sustain effective gains up to 60 000 in a helium-isobutane counter gas mixture at atmospheric pressure. Consequently, high signal-to-noise ratios were achieved (electronic noise ~500 electrons r.m.s) thereby permitting adequate X-ray energy resolution. [ABSTRACT FROM AUTHOR]

Abstract: A Gas Electron Multiplier with Micro-Induction Gap Amplifying Structure (GEM-MIGAS) is formed when the induction gap of the GEM is set between 50 and 100μm using kapton pillars spaced at regular intervals. This configuration combines the properties of a GEM and Micromegas, allowing operation in tandem to generate high charge gains. We measured the essential operational parameters of this system using argon–isobutane (IB) and helium–IB gas mixtures. The present short induction gap GEM was able to achieve effective gains exceeding 2×104 using argon–IB and 105 using helium–IB mixtures. In view of the high gains achieved, particularly when using helium-based gas mixtures, these studies confirmed the possibility of using the present system for high-performance sub-keV X-ray detection. [Copyright &y& Elsevier]

Abstract: Experimental work was carried out to evaluate the performance of a Gas Electron Multiplier (GEM) operated with a micromesh readout plane that enabled the induction gap to be set at 50μm. We measured the essential operational parameters of this system using Ar(75%)-isobutane (25%) as the counter gas mixture. The measurements included the effective gain, effective gain stability, and the X-ray energy resolution using a 5.89keV X-ray source. These studies demonstrated several advantages of the current system when compared with the standard operation, such as lower operational voltages, higher effective gains and improved effective gain stability. [Copyright &y& Elsevier]

Abstract: Utilizing both steady state gain and bandwidth information of the process open loop transfer function elements, this paper presents a new dynamic loop pairing criterion for decentralized control of multivariable processes. Through defining an effective gain matrix, the loop pairing procedures of popular relative gain array method is directly extended to the new method which can reflect dynamic loop interactions under finite bandwidth control. Compared with existing methods, this method is simple, effective, and easy to be understood and applied by control engineers. Several examples, for which the RGA based loop pairing criterion gives an inaccurate interaction assessment, are employed to demonstrate the effectiveness of the proposed method. [Copyright &y& Elsevier]

Abstract: The Micro-Hole and Strip Plate (MHSP) is a hybrid electron multiplier which combines the working principles of a Gas Electron Multiplier (GEM) and a Micro-Strip Gas Counter (MSGC). The compact double stage electron multiplication processes found in the MHSP enables the realisation of higher gas gain than the lone GEM operation. Thermal neutron detection using gas detectors involves the use of gas with another suitable stopping gas, operated at elevated pressure to confine the products of the neutron- reaction. It is, however, well known that the gain of GEMs drops too sharply with increasing chamber pressure. We have pursued experimental work using the MHSP to infer the upper limits of thermal neutron position resolution. The stopping gas used during the present studies was Tetrafluoromethane chosen due to its low X-ray and -ray efficiency, requiring only 2.6bar to yield a position resolution of 1mm. In the present studies, systematic measurements were taken to establish the gain versus pressure characteristics of the MHSP, in the 1 to 2.65bar range. These studies demonstrated that it was possible to sustain gains above and 300 with pressures of 1 and 2.65bar, respectively. The advantage of having two multiplication stages in the MHSP separated by only few tens of microns, results in a less pronounced gain reduction with pressure, presenting higher gains than single or multiple GEMs. The energy resolution at 1bar was 29% FWHM for the 5.9keV Mn line from a source, which is a typical value for micro-patterned gas detectors operating in . [Copyright &y& Elsevier]