Sound Amplification Research Articles

The influence of cochlear implantation on aggression behaviors in children

ObjectiveIt has been suggested that children with higher degree of hearing loss may show more severe externalizing (e.g., aggression) and internalizing (e.g., depression and anxiety) behavioral problems compared to that of their normally hearing peers. The purpose of this study was to investigate the influence of sound amplification through cochlear implants (CIs) on aggressive behaviors in Persian children. MethodsDuring a prospective study design, 72 children (40 girls, 32 boys) who underwent unilateral implantation and 72 (40 girls, 32 boys) age-matched normally hearing children (control group) participated. All CI children had age of <4 years at the time of implantation. The Aggression Scale for Preschoolers (ASFP) was utilized to measure various types of aggression including verbal aggression, physical aggression, relational aggression, and impulsive anger. The speech performance of children was also evaluated using Speech Intelligibility Rating (SIR). The ASFP and SIR measurements were conducted at the pre-implantation phase and at 6, 12, and 18 months post-implantation period. ResultsA repeated measures analysis of variance showed significant reduction in ASFP scores from “pre-operation” to “post-operative” conditions in CI group. However, aggression level in CI recipients were significantly higher than children in control group. In the analyses of ASFP subscales, we found a reduction and a consequent improvement in verbal aggression, physical aggression and impulsive anger. However, no significant difference was found in relational aggression across various time intervals. Furthermore, children who received CI before 2 years old exhibited better aggression level than children who received their devices at later ages. The significantly negative correlation (r = −0.76, p < 0.001) was found between the SIR and ASFP scores, so that lower speech intelligibity ability scores were associated with more aggressive behavior problems. ConclusionThis study suggests that young children with noticeable degree of hearing loss may experience higher level of aggression compared to normally hearing peers. However, when they undergo early implantation and attend at regular post-operative rehabilitation programs, their aggression status will improve seriously.

Insertion loss of asymmetrical balconies on a building façade

The acoustical insertion loss of asymmetrical balconies on high-rise buildings was studied experimentally using a 1:3 scaled down model in the present study. Four balcony forms featured by the presence of a full-height side-wall were included. A linear loudspeaker array was adopted as the sound source. The effects of source orientation and balcony elevation angle on the insertion loss and its spectral variation were examined. The position of the full-height side-wall relative to the sound source significantly affects the balcony insertion loss. It is observed that the maximum traffic noise amplification and attenuation are both ∼6 dBA. Results also suggest that the balustrade has no effect on the insertion loss spectral variation pattern, though the insertion loss magnitude could be much reduced without it in the presence of a short side-wall. This short side-wall determines the insertion loss spectral variation pattern. Significant sound amplification is found at frequencies of the odd order transverse modes, the longitudinal modes, and their coupled modes regardless of balcony form and elevation angle. It is also found that the major acoustic mode interactions are basically independent of source orientation for balconies without the short side-wall.

Consumer Opinion of Personal Sound Amplification Products: A Preliminary Sentiment Analysis.

Purpose The purpose of this study was to preliminarily investigate the sentiments associated with consumer opinions of personal sound amplification products (PSAPs). Method Online reviews of 21 popular PSAPs were collected from the Amazon.com website. The reviews for each product were exported to compile individual product-specific text files. A sentiment mining analysis was completed to aggregate the number of positive and negative comments for each product. In addition, the effect of value for money, available features, perceived benefit, and overall perception of PSAPs was evaluated. A correlational analysis was completed to examine the relationship between different PSAP features and the number of positive and negative comments. Results Mixed-model analysis of variance showed a significantly higher number of positive comments for high- and mid-cost products in terms of overall perception and perceived benefit compared to low-cost products. For feature attribute, high-cost products had significantly higher positive comments compared to mid- and low-cost products. There was a strong correlation between price and positive comments and a moderate correlation between price and negative comments. Also, there was a significant moderate correlation between presence of compression and feedback suppression PSAP features and positive comments. Conclusions Positive sentiments expressed toward PSAPs were found to favor high- and mid-level products. However, there was a considerably high number of negative sentiments reported across all the PSAPs investigated. The noticeable thing is that the negative comments do not change significantly across price ranges. However, the positive comments significantly increase with an increase in product price range. This indicates a possible increase in benefit with high-cost products. However, this claim requires further empirical evidence through controlled studies.

Electronic Amplifier for Modern Acousto-Optical Spectrometers

The paper presents an analysis of electronic amplifiers for modern acousto-optical spectrometers, based on two-crystal sequential diffraction of incident radiation by acoustic waves propagating in each acousto-optical (AO) cell. Such a diffraction scheme has a higher spectral resolution, retaining all the other advantages of traditional AO spectrometers. A description of the functional block diagram of a two-crystal AO spectrometer is given, and the necessary requirements for electronic units are indicated. The results of joint use of the signal power amplification device and a previously developed wideband frequency synthesizer for exciting sound waves in AO cells are presented; output amplitudes of amplified signals are obtained.

Analog Computer Development in Germany With a Focus on Telefunken [Scanning Our Past

Until the 1930s, analog computers were mostly mechanical and sometimes electromechanical devices that were clumsy, required significant maintainance, and were difficult to reprogram. Reprogramming required the operators to dismantle and rebuild an intricate maze of axles and gears interconnecting the various computing elements. With the advent of electronics, the idea of a purely electronic analog computer was ripe in the late 1930s and early 1940s. The first such machine was devised and built by George A. Philbrick in 1938 and became known as Polyphemus, due to its particular shape-a rack containing a lot of electronic amplifiers and associated equipment with a single oscilloscope mounted on top, which looked a bit like the one-eyed giant.

Directing Cymbeline: Leon activated attributes of God for the 38th Bali Arts Festival 2016

Applying the theory of Bali Creative Art, this paper looks at the theatre directing elements, concept, and method applied by Leon Rubin when he directed Shakespeare’s Cymbeline. Invited by the Head of the Bali Province Cultural Directorate to showcase a cross-cultural theatrical production, Leon selected and integrated twenty-five artists (actors/actresses, costume and lighting designers) from Bali, Indonesia; Malaysia, Mexico, Brazil, China, and England in a new work for the 38th Bali Arts Festival in 2016. Most of the actors were able to stay in Bali for three weeks to rehearse; the piece was also shown in limited seating venues in the villages of Ubud and Abian Semal for three nights in a row from 25 to 27 June 2016. Despite the great challenge for the non-Indonesian actors and director, all were finally able to collaborate under Leon’s direction and perform the Indonesian language translation of the original Shakespearian text. Although the local artists informed Leon that the Cymbeline play would be competing with sounds from loud speakers in several nearby performance venues and the stage crew offered the actors microphones—Leon did not allow sound amplification of the actors, musicians, narrator, or the singer. Surprising yet amusing local audiences with several uncommon features, the Cymbeline show was considered to be the best collaborative production among the nearly 350 performances presented during the month-long festival.

INTERDISCIPLINARY INTEGRATION IN A MEDICAL UNIVERSITY: PROPEDEUTICS OF INTERNAL DISEASES AND MEDICAL AND BIOLOGICAL PHYSICS.

This paper highlights the issues on interdisciplinary integration of the disciplines as the propedeutics of internal diseases and medical and biological physics studied by students of medical and dental faculties. It has been shown that the integration of these disciplines is the most pronounced when studying acoustic wave methods of investigation in the clinical practice; hydro- and hemodynamics and their role in diagnosing the cardiovascular diseases, and, in particular the rheological properties of blood, the hydraulic resistance of blood vessels. Considerable attention is paid to explaining the physical basics of electrocardiography. Acoustic wave investigation techniques in the clinical practice, percussion and auscultation first and foremost are very important test-timed techniques, especially when diagnosing the broncho-pulmonary system. While studying the propedeutics of internal diseases, students acquire concepts for applying the percussion and analysing the characteristic sounds heard: the principle of resonance, the percussion sphere. The medical students’ ability to understand the mechanisms of changes that occur in certain pathologies creates the basis for a deeper analysis of the dynamics of these processes. Students analyze the characteristics of sounds and noises of varying intensity, which are created by tissues of different density, by airless organs in response to the amplification of percussion sounds. When studying the auscultation technique, the students acquire knowledge and skills to differentiate sounds, tones and noises produced by the functioning of internal organs. The section of medical and biological physics devoted to hydro- and hemodynamics is important for stronger understanding the blood circulation through the cardiovascular system in the human body and for diagnosing and treating diseases of this system. Students will learn about the causes of turbulent flow, functional and organic noise in the heart area and their connection with the phases of cardiac activity. The article has also demonstrated the integration of the physical fundamentals of electrocardiography into practical medicine.

Frequency-tripling OEO based on frequency multiplication in saturated electronic amplifier

A Frequency-Tripling optoelectronic oscillator (FT-OEO) based on frequency multiplication in a saturated in-loop electronic amplifier has been proposed and demonstrated. The significant 3rd harmonic signal generated at the saturated amplifier is coupled out and filtered as the desired output. A prototype of the FT-OEO is constructed, where the fundamental oscillating signal (fosc) locates at 2 GHz. The generated 6 GHz frequency-tripling signal (3fosc) is of 0 dB m and the phase noise is −108dBc/Hz @ 1 kHz and −130dBc/Hz @ 10 kHz. Under external injection, the side modes are suppressed to below −110dBc/Hz. This FT-OEO provides a compact and cost-efficient scheme for frequency multiplication of OEO so as to alleviate the bandwidth limit of electro-optic components.

Modeling cochlear micromechanics: hypotheses and models

Abstract The cochlea plays an important role in the mammalian auditory system. Sound-induced cell motion in the cochlea is transformed into electrical signals that are then sent to primary auditory neurons. The most significant feature of the cochlea is the active and nonlinear amplification of faint sounds. This active process cannot be explained via a simple hydromechanical representation of the cochlea, that is, a macromechanic explanation. Although the mechanisms of this amplification are not well understood, cochlear micromechanical behavior is thought to play a significant role. The measurement of in vivo cochlea micromechanical responses is challenging and restricted by technical limitations. Modeling the micromechanics of the cochlea, however, can facilitate the interpretation of experimental observations. In this paper, we reviewed studies in which researchers modeled the cochlear micromechanics, and we discussed various modeling hypotheses, outcomes, and expectations.

Clinical Performance Evaluation of a Personal Sound Amplification Product vs a Basic Hearing Aid and a Premium Hearing Aid

Hearing loss is a highly prevalent condition with multiple negative associated outcomes, yet few persons with hearing loss have hearing aids (HAs). Personal sound amplification products (PSAPs) could be an alternative low-cost solution to HAs, but data are lacking on the performance of PSAPs. To evaluate the clinical efficacy of a PSAP by comparing its performance with that of a basic HA and a premium HA in participants with mild, moderate, and moderately severe hearing impairment. A prospective, single-institution cohort study was performed with a total of 56 participants, including 19 with mild hearing loss, 20 with moderate hearing loss, and 17 with moderately severe hearing loss. All participants underwent 4 clinical hearing tests with each of the PSAP, basic HA, and premium HA, and all completed an evaluative questionnaire. All hearing devices (PSAP, basic HA, and premium HA) were applied by a clinician to prevent bias and order effects; participants were blinded to the device in use, and sequence of devices was randomized. The study used the Korean version of the hearing in noise test, the speech intelligibility in noise test, listening effort measurement using a dual-task paradigm, pupillometry, and a self-rating questionnaire regarding sound quality and preference. These tests were administered under the following 4 hearing conditions: unaided hearing, use of PSAP, use of basic HA, and use of premium HA. The study included 56 participants with a mean age of 56 years (interquartile range, 48-59 years); 29 (52%) were women. In the mild and moderate hearing loss groups, there was no meaningful difference between PSAP, basic HA, and premium HA for speech perception (Cohen d = 0.06-1.05), sound quality (Cohen d = 0.06-0.71), listening effort (Cohen d = 0.10-0.92), and user preference (PSAP, 41%; basic HA, 28%; premium HA, 31%). However, for the patients with moderately severe hearing loss, the premium HA had better performance across most tests (Cohen d = 0.60-1.59), and 70% of participants preferred to use the premium HA. The results indicate that basic and premium HAs were not superior to the PSAP in patients with mild to moderate hearing impairment, which suggests that PSAPs might be used as an alternative to HAs in these patient populations. However, if hearing loss is more severe, then HAs, especially premium HAs, should be considered as an option to manage hearing loss.

The 2-inches VSiPMT industrial prototypes

Photon detection is a key factor to study many physical processes in several areas of fundamental physics research. Focusing the attention on photodetectors for particle astrophysics, we understand that we are very close to new discoveries and new results. In order to push the progress in the study of very high-energy or extremely rare phenomena (e.g. dark matter, proton decay, neutrinos from astrophysical sources) the current and future experiments require additional improvements in linearity, gain, quantum efficiency and single photon counting capability. To meet the requirements of these classes of experiments, we propose a new design for a modern hybrid photodetector: the VSiPMT (Vacuum Silicon PhotoMultiplier Tube).The idea is to replace the classical dynode chain of a PMT with a SiPM, which therefore acts as a single stage Geiger electron detector and amplifier, without statistical fluctuations. The aim is to match the large sensitive area of a photocathode with the performances of the SiPM technology. The previous VSiPMT prototypes already showed many attractive features such as low power consumption, very large dynamic range, excellent photon counting capability and low voltage driven gain.We now present the results of the full characterization of the latest and largest version achieved up to now, a 2-inches VSiPMT manufactured by Hamamatsu.

Applying the COM-B Model to Assess the Usability of Smartphone-Connected Listening Devices in Adults with Hearing Loss.

Unlike conventional hearing aids, smartphone-connected listening devices may require limited or no input from a trained audiologist in terms of device programming and adjustment. However, there is a lack of peer-reviewed evidence assessing the real-world perspectives of people living with hearing loss toward such technological innovations. This study assessed the everyday experiences of adults living with hearing loss toward a range of smartphone-connected listening devices using the Capability, Opportunity, Motivation, Behaviour (COM-B) model as a theoretical framework. A qualitative study where participants trialed one of the following smartphone-connected listening devices for two weeks in their everyday lives: made-for-smartphone hearing aid, personal sound amplification product, and smartphone "hearing aid" app with wired earphones or wireless hearable. Individual semistructured interviews were conducted. Twenty adults (13 male and 7 female; mean age = 62.25 years, SD = 11.59) with mild-to-moderate hearing loss (mean better ear pure-tone average = 30.49 dB HL, SD = 17.51) were recruited using a convenience sampling strategy. All participants owned conventional hearing aids. The data were analyzed using an established deductive thematic analysis procedure within the context of the COM-B model. The model stipulates that for individuals to engage in a particular behavior (B), they must have sufficient capability (C), opportunity (O), and motivation (M). Capability: One of the key advantages facilitating use and adherence of smartphone-connected listening devices was the ability for participants to make fine-tune adjustments in any listening situation. Opportunity: Participants commented that these devices could address issues surrounding stigma as smartphones are ubiquitous in everyday life. Motivation: Participants consistently reported that the ability to make adjustments via a smartphone provided them with a greater sense of autonomy and empowerment. As a result, they felt more in control of their hearing loss. This study lays the foundation for further high-quality research to explore whether smartphone-connected technologies have the potential to yield optimum benefits for people living with hearing loss.

Modular and scalable control and data acquisition system for power hardware in the loop (PHIL) amplifiers

This study presents a newly developed modular system for control of power electronic amplifiers in high-power, high-frequency power hardware in the loop experiments. The proposed design comprises computational nodes connected via multi-gigabit fibre-optic links. Nodes are modular and reconfigurable, allowing interfacing with a range of sensors and actuators, typically voltage and current sensors, and switching converters. The system has been designed for scalability to permit arbitrarily high power ratings and fidelity to be achieved through paralleling and interleaving of multiple power converter modules, targeting an ultimate sample and control rate of 1 MHz. Experimental validation is presented using a two-node configuration to facilitate a power electronic experiment operating at 120 Vrms and 10 Arms, with a fundamental frequency of 50 Hz and frequency content up to the 11th harmonic.

The outcome of stapedotomy in adult patients with clinical otosclerosis in Erbil

Background and objective: Otosclerosis is a primary disease of the temporal bone that leads to stapes fixation. Hearing loss and tinnitus are the main symptoms. Treatment includes surgery, medical treatment, and sound amplification therapy alone or in combination. This study aimed to evaluate the functional outcomes of patients with clinical diagnosis of otosclerosis undergoing primary stapes surgery in Erbil city. Methods: A retrospective descriptive study. A total of 32 patients with clinical otosclerosis underwent unilateral stapedotomy in the specialized center between September 2011 and September 2013. These included 20 females and 12 males, aged 21 to 48 years, their mean age (±SD) was 31.9 (±10.91) years. Results: The average preoperative and postoperative air conduction threshold was 51.13 and 23.91 dB, respectively. The mean preoperative and postoperative bone conduction threshold was 21.53 and 16.21dB, respectively. The average preoperative and postoperative air-bone gap was 29.03 and 8.51 dB, respectively. All 32 ears (100%) had a residual air-bone gap <10 dB. Conclusion: Stapes surgery showed significant functional hearing outcomes in this study. The very significant reduction in the air-bone gap is a good indicator of the success of the surgery.

AGILE development and silicon detector

In the years 1980s and 1990s, a very fast and important progress on position and energy loss measurements of elementary particles was obtained by the use of Si strip detector in high energy (HE) experiments. The number of strips has been increasing at any improvement of the tracker device. The high number of strip density also pushed the power reduction of the readout electronic amplifiers. The Si tracker became at certain moment a challenging substitute of the classical spark chambers (Fichtel et al. NASA-TM-X-70761, 1995; Thompson arXiv:e:0811.0738, 2008), in use for tracking particles in space experiments. In particular in HE $$\gamma $$-strophysics, the photon direction was derived by measuring that of the positron electron pair produced in high Z material interlaid in the planes of the spark chamber. See for instance the EGRET figure in the text. AGILE and GLAST (renamed Fermi after launch) are the most successful examples of the Si revolution.

Van der Waals 2D layered-material bipolar transistor

Ultrathin and light heterojunction bipolar transistors based on two-dimensional (2D) layered materials with flexible semiconducting properties have been considered for several electronic applications. In this paper, a van der Waals p-BP/n-MoS2/p-BP BJT is demonstrated. It is fabricated using mechanical exfoliation, where a dry transfer technique is used to stack a vertical double heterojunction. The device structure includes nanoflakes of black phosphorus (BP) and MoS2. The current–voltage characteristics of the common–emitter and common–base configurations are examined. These p-BP/n-MoS2/p-BP bipolar transistors exhibit current–voltage characteristics similar to those of conventional p-n-p bipolar transistors. Devices with thin MoS2 layers show good saturation current–voltage characteristics, and a maximum common–emitter current gain (β = IC/IB) of approximately 10.1 is obtained at room temperature (300 K). Furthermore, the thickness dependence of the base region (n-MoS2) is investigated for the common–emitter output electrical characteristics (VCE − IC) of a double heterojunction bipolar transistor in which the emitter is grounded. The collector current decreases as the thickness of n-MoS2 is increased. This study can pave the way for the application of 2D materials as controllable amplifiers in flexible electronics.

A study on relationship between pulsatile tinnitus and temporal bone pneumatization grade

Pulsatile tinnitus (PT) is a common symptom in otology. In some cases, the venous flow in the sigmoid sinus (SS) is the source of PT. It is suggested that the venous sound is propagated into the tympanic cavity through the air pathway of temporal bone air cells (TBAC). The hyperpneumatization of TBAC was hypothesized as a direct pathology of PT through amplifying the venous sound, but there is no quantitative analysis. This study aims to quantify the relationship between the venous sound amplification and the pneumatization grade of TBAC. The acoustic numerical simulation and statistical analysis were performed based on the radiology data of 21 pulsatile tinnitus patients. The TBAC of these patients were classified into hypopneumatization, normal pneumatization and hyperpneumatization grades according to three standards. The in vitro acoustic experiment was done as the validation of simulation. It is indicated that the SS standard is effective for the clinical evaluation of venous sound amplification. The TBAC amplifies the venous sound due to the acoustic resonance at the first mode frequency, regardless of the pneumatization grades. The normal pneumatic TBAC exhibits the highest sound amplification effect on the venous sound amongst the three grades, contributing mostly to PT, but would not induce PT without any other causes.

Polymeric foams for flexible and highly sensitive low-pressure capacitive sensors

Flexible low-pressure sensors ( <10 kPa) are required in areas as diverse as blood-pressure monitoring, human–computer interactions, robotics, and object detection. For applications, it is essential that these sensors combine flexibility, high sensitivity, robustness, and low production costs. Previous works involve surface micro-patterning, electronic amplification (OFET), and hydrogels. However, these solutions are limited as they involve complex processes, large bias voltages, large energy consumption, or are sensitive to evaporation. Here, we report a major advance to solve the challenge of scalable, efficient and robust e-skin. We present an unconventional capacitive sensor based on composite foam materials filled with conductive carbon black particles. Owing to the elastic buckling of the foam pores, the sensitivity exceeds 35 kPa−1 for pressure <0.2 kPa. These performances are one order of magnitude higher than the ones previously reported. These materials are low-cost, easy to prepare, and display high capacitance values, which are easy to measure using low-cost electronics. These materials pave the road for the implementation of e-skin in commercialized applications.

Theory of applying shear strains from boundary walls: Linear response in glasses.

We construct a linear response theory of applying shear deformations from boundary walls in the film geometry in Kubo's theoretical scheme. Our method is applicable to any solids and fluids. For glasses, we assume quasi-equilibrium around a fixed inherent state. Then, we obtain linear-response expressions for any variables including the stress and the particle displacements, even though the glass interior is elastically inhomogeneous. In particular, the shear modulus can be expressed in terms of the correlations between the interior stress and the forces from the walls. It can also be expressed in terms of the inter-particle correlations, as has been shown in the previous literature. Our stress relaxation function includes the effect of the boundary walls and can be used for inhomogeneous flow response. We show the presence of long-ranged, long-lived correlations among the fluctuations of the forces from the walls and the displacements of all the particles in the cell. We confirm these theoretical results numerically in a two-dimensional model glass. As an application, we describe emission and propagation of transverse sounds after boundary wall motions using these time-correlation functions. We also find resonant sound amplification when the frequency of an oscillatory shear approaches that of the first transverse sound mode.

OHC-TRECK: A Novel System Using a Mouse Model for Investigation of the Molecular Mechanisms Associated with Outer Hair Cell Death in the Inner Ear

Outer hair cells (OHCs) are responsible for the amplification of sound, and the death of these cells leads to hearing loss. Although the mechanisms for sound amplification and OHC death have been well investigated, the effects on the cochlea after OHC death are poorly understood. To study the consequences of OHC death, we established an OHC knockout system using a novel mouse model, Prestin-hDTR, which uses the prestin promoter to express the human diphtheria toxin (DT) receptor gene (hDTR). Administration of DT to adult Prestin-hDTR mice results in the depletion of almost all OHCs without significant damage to other cochlear and vestibular cells, suggesting that this system is an effective tool for the analysis of how other cells in the cochlea and vestibula are affected after OHC death. To evaluate the changes in the cochlea after OHC death, we performed differential gene expression analysis between the untreated and DT-treated groups of wild-type and Prestin-hDTR mice. This analysis revealed that genes associated with inflammatory/immune responses were significantly upregulated. Moreover, we found that several genes linked to hearing loss were strongly downregulated by OHC death. Together, these results suggest that this OHC knockout system is a useful tool to identify biomarkers associated with OHC death.