dB Range Research Articles

Broadband and High-Capacity Silicon Photonics Single-Sideband Modulator

We propose a novel photonic-integrated single-sideband (SSB) modulator realized in silicon on insulator technology operating either in suppressed-carrier or full-carrier mode with continuously tunable carrier-to-sideband ratio (CSBR). Large rejection levels of the spurious sidebands and residual carrier in excess of 40&#x00A0;and 30&#x00A0;dB, respectively, with a CSBR tunability over a <inline-formula><tex-math notation="LaTeX">$\sim$</tex-math></inline-formula>&#x00A0;50&#x00A0;dB range, are demonstrated. By employing a single silicon photonics (SiP) phase modulator and a compact and high-performance filtering element, the proposed architecture exhibits a compact layout and tolerates high driving voltage levels, leading to large OSNR values of the modulated sideband in excess of 50&#x00A0;dB. The device supports broadband RF data signals and its operation is tested with an up to 5&#x00A0;Gbps ASK-modulated carrier at 16.5&#x00A0;GHz, limited by available RF equipment. Furthermore, the technique allows to implement a frequency-multiplication mechanism for the input RF carrier, and up to threefold effective bandwidth enhancement of the SiP modulator is obtained by generating an optical SSB signal with a modulated spectral component spaced by 49.5&#x00A0;GHz from the optical carrier. Such features are promising for implementing cost-effective optical distribution of millimeter-wave wireless data signals supporting the evolution of next-generation radio access networks.

Salvage intratympanic steroid therapy for sudden sensorineural hearing loss: our real-life experience in 32 patients

To examine the role of salvage intratympanic steroid injections in patients presenting with idiopathic sudden sensorineural hearing loss following a poor response to initial oral steroid treatment. A retrospective analysis of patient records over the course of four years was conducted, and pure tone thresholds were reviewed before treatment, after oral steroid therapy and six weeks after intratympanic steroid injection therapy. After oral steroid therapy alone, there was a mean average threshold change of 6.2 dB HL (range, -13.8-33.8 dB). This change was statistically significant for severely affected patients (those with an average presenting threshold of over 71 dB). The mean average threshold improvement following intratympanic steroid injection therapy was 2.9 dB (range, -22.5-61.3 dB); this was not statistically significant. Some patients experienced moderate improvement following intratympanic steroid injection therapy; however, no specific subgroup was identified to benefit more from intratympanic steroid injection therapy.

Investigation of thermo-acoustic and mechanical performance of gypsum-plaster and polyester fibers based materials for building envelope

Buildings are one of the main consumers of energy in the world and it is pushing the scientific community to find alternative solutions to improve the thermal insulation of building envelope. The selection of appropriate building materials is an important challenge for improving thermal comfort and energy performance of buildings. In this scenario, the interest of gypsum-plaster based composites is increasing. In this investigation, new plaster-based composites with polyester fibers were produced and tested at lab scale, in order to obtain cheap solutions with improved thermo-acoustic performance. The results show that it is possible to improve the thermal, mechanical, and acoustic performance of construction biomaterials by using plaster as a binder and polyester fibers as reinforcement: thermal conductivity was equal to 0.20 W/m.K, the compressive strength to about 4 MPa, and the transmission loss in the 40–45 dB range. When compared to the plaster without fibers, thermal conductivity was reduced by about 29%, mechanical resistance was increased by about 76%, and absorption coefficient was reduced by about 48%.

Highly Configurable 100 Channel Recording and Stimulating Integrated Circuit for Biomedical Experiments

This paper presents the design results of a 100-channel integrated circuit dedicated to various biomedical experiments requiring both electrical stimulation and recording ability. The main design motivation was to develop an architecture that would comprise not only the recording and stimulation, but would also block allowing to meet different experimental requirements. Therefore, both the controllability and programmability were prime concerns, as well as the main chip parameters uniformity. The recording stage allows one to set their parameters independently from channel to channel, i.e., the frequency bandwidth can be controlled in the (0.3 Hz–1 kHz)–(20 Hz–3 kHz) (slow signal path) or (0.3 Hz–1 kHz)–4.7 kHz (fast signal path) range, while the voltage gain can be set individually either to 43.5 dB or 52 dB. Importantly, thanks to in-pixel circuitry, main system parameters may be controlled individually allowing to mitigate the circuitry components spread, i.e., lower corner frequency can be tuned in the 54 dB range with approximately 5% precision, and the upper corner frequency spread is only 4.2%, while the voltage gain spread is only 0.62%. The current stimulator may also be controlled in the broad range (69 dB) with its current setting precision being no worse than 2.6%. The recording channels’ input-referred noise is equal to 8.5 µVRMS in the 10 Hz–4.7 kHz bandwidth. The single-pixel occupies 0.16 mm2 and consumes 12 µW (recording part) and 22 µW (stimulation blocks).

Hybrids of glass fibers coated with carbon nanotubes and nickel for high‐performance electromagnetic wave absorption composites

AbstractTo expand the application of insulating glass fiber (GF) in the field of microwave absorption, one type of GF hybrids with carbon nanotubes (CNTs) and nickel (Ni) was successfully synthesized by chemical vapor deposition and electroless plating methods. By changing the reaction conditions, the morphology of GF hybrids including CNT's length, CNT's growth density, and Ni′s thickness could be adjusted. The as‐produced hybrids were used as multifunctional reinforcement to fabricate epoxy composites. The dielectric properties of composites were particularly measured from 1 to 18 GHz. It was found that the variation of GF hybrids structure significantly changed the dielectric properties of the composites in the tested frequency range. Furthermore, the analytical simulation work based on the experimental results was conducted for optimizing the structural parameters of multilayered composites. The results showed that the best reflection loss of −60 dB with a −10 dB range of 5.6 GHz could be obtained in an absorber with a triple‐layered structure composed by GF‐CNTs/epoxy with different CNT contents and GF‐CNTs@Ni/epoxy. Thus, the proposed hybrid method might be quite efficient for developing composites that can achieve high‐performance electromagnetic absorbing.

Cochlear Implantation Outcomes in Observed Vestibular Schwannoma: A Preliminary Report.

Over the last decade there has been a trend toward observation for small nongrowing vestibular schwannoma (VS). Even without tumor growth, patients commonly experience ipsilateral hearing decline, and hearing rehabilitation remains challenging. This study analyzes hearing and speech performance outcomes after cochlear implantation (CI) in observed VS. Retrospective review. Tertiary referral center. Chart review was used to include patients with observed VS who had undergone ipsilateral CI, pre- and postimplantation audiometry, and speech performance. Tumor size pre- and postimplantation was measured with volumetric analysis. Seven patients with ipsilateral VS and CI were identified. Preimplantation tumor volume was 0.11 to 1.02 cm3. Five subjects were implanted with a straight electrode and two with a perimodiolar electrode. The average preimplant pure tone average was 91.3 dB (range, 80-117 dB) and 61.2 dB (range, 12-118 dB) for the implanted and nonimplanted ears, respectively. In all subjects with at least 1 year of listening experience (n = 6), consonant-nucleus-consonant word scores improved at 6 months and 1 year in the CI-alone and bimodal listening conditions. AzBio scores in quiet also improved at 6 months and 1 year. Of subjects with serial pre- and postoperative magnetic resonance imaging, volumetric analysis demonstrated no tumor growth. Our results demonstrate that CI is a successful option for subjects with small nongrowing VS. All subjects had improved performance postimplantation. VS may continue to be observed with serial magnetic resonance imaging given increasing conditionality among CI manufacturers and ability to assess cerebellopontine angle extension despite implant artifact.

No Interface, No Problem: Gesture Recognition on Physical Objects Using Radar Sensing.

Physical objects are usually not designed with interaction capabilities to control digital content. Nevertheless, they provide an untapped source for interactions since every object could be used to control our digital lives. We call this the missing interface problem: Instead of embedding computational capacity into objects, we can simply detect users’ gestures on them. However, gesture detection on such unmodified objects has to date been limited in the spatial resolution and detection fidelity. To address this gap, we conducted research on micro-gesture detection on physical objects based on Google Soli’s radar sensor. We introduced two novel deep learning architectures to process range Doppler images, namely a three-dimensional convolutional neural network (Conv3D) and a spectrogram-based ConvNet. The results show that our architectures enable robust on-object gesture detection, achieving an accuracy of approximately 94% for a five-gesture set, surpassing previous state-of-the-art performance results by up to 39%. We also showed that the decibel (dB) Doppler range setting has a significant effect on system performance, as accuracy can vary up to 20% across the dB range. As a result, we provide guidelines on how to best calibrate the radar sensor.

The STArgardt Remofuscin Treatment Trial (STARTT): design and baseline characteristics of enrolled Stargardt patients

Background: This report describes the study design and baseline characteristics of patients with Stargardt disease (STGD1) enrolled in the STArgardt Remofuscin Treatment Trial (STARTT). Methods: In total, 87 patients with genetically confirmed STGD1 were randomized in a double-masked, placebo-controlled proof of concept trial to evaluate the safety and efficacy of 20 milligram oral remofuscin for 24 months. The primary outcome measure is change in mean quantitative autofluorescence value of an 8-segment ring centred on the fovea (qAF8). Secondary efficacy variables are best corrected visual acuity (BCVA), low-luminance visual acuity (LLVA), mesopic microperimetry (mMP), spectral domain optical coherence tomography (SD-OCT), reading speed on Radner reading charts, and patient-reported visual function as assessed by the National Eye Institute Visual Functioning Questionnaire 25 (NEI VFQ-25) and Functional Reading Independence (FRI) Index. Results: Mean age of participants was 35±11 years with 49 (56%) female. Median qAF8 value was 438 Units (range 210-729). Median BCVA and LLVA in decimal units were 0.50 (range 0.13-0.80) and 0.20 (range 0.06-0.63), respectively. The median of the mean retinal sensitivity with mMP was 20.4 dB (range 0.0-28.8). SD-OCT showed median central subfield retinal thickness of 142 µm (range 72-265) and median macular volume of 1.65 mm3 (range 1.13-2.19). Compared to persons without vision impairment, both reading performance and patient-reported visual function were significantly lower (p&lt;0.001, one sample t-test). Mean reading speed was 108±39 words/minute with logRAD-score of 0.45±0.28. Mean VFQ-25 composite score was 72±13. Mean FRI Index score 2.8±0.6. Conclusions: This trial design may serve as reference for future clinical trials as it explores the utility of qAF8 as primary outcome measure. The baseline data represent the largest, multi-national, STGD1 cohort to date that underwent standardized qAF imaging, reading speed assessment and vision-related quality of life measures which all contribute to the characterization of STGD1. EudraCT registration: 2018-001496-20 (09/05/2019)

Deep learning-driven opportunistic spectrum access (OSA) framework for cognitive 5G and beyond 5G (B5G) networks

The evolving 5G and beyond 5G (B5G) wireless technologies are envisioned to provide ubiquitous connectivity and great heterogeneity in communication infrastructure by connecting diverse devices and providing multifarious services. Recently, the Internet of Things (IoT) and unmanned aerial vehicles (UAVs) are realized as an essential component of the upcoming 5G/B5G networks, enabling enhanced communication capacity, high reliability, low latency, and massive connectivity. However, one limiting factor in the expansion of 5G/B5G technology is the finite radio spectrum, which necessitates managing the anticipated spectrum crunch for future wireless networks. One potential solution is to develop intelligent cognitive methods to dynamically optimize the use of spectrum in 5G/B5G networks to solve the imminent problem of spectrum congestion and improve radio efficiency. This paper addresses the opportunistic spectrum access (OSA) problem in the 5G/B5G cognitive radio (CR) network of IoTs and UAVs through the novel deep learning-based detector, dubbed as Deep-CRNet. The proposed detector employs residual connections with cascaded multi-kernel convolutions to identify the primary user (PU) spectrum usage by extracting the inherent multi-scale signal and noise features in the sensed transmission patterns. Thereby, Deep-CRNet intelligently learns and locates the spectrum holes so that secondary users (SUs) and PUs can dynamically share network spectrum resources. The efficacy of Deep-CRNet is validated through simulation results, where it achieved 99.74% accuracy with 99.65% precision and 99.83% recall in accurately classifying the PU status. In addition, the average correct detection probability of Deep-CRNet in the low signal-to-noise ratio (−20 dB to −15 dB) range is 38.21% higher than the second best-performing detector.

A Review and Meta-Analysis of Underwater Noise Radiated by Small (&lt;25 m Length) Vessels

Managing the impacts of vessel noise on marine fauna requires identifying vessel numbers, movement, behaviour, and acoustic signatures. However, coastal and inland waters are predominantly used by ‘small’ (&lt;25 m-long) vessels, for which there is a paucity of data on acoustic output. We reviewed published literature to construct a dataset (1719 datapoints) of broadband source levels (SLs) from 17 studies, for 11 ‘Vessel Types’. After consolidating recordings that had associated information on factors that may affect SL estimates, data from seven studies remained (1355 datapoints) for statistical modelling. We applied a Generalized Additive Mixed Model to assess factors (six continuous and five categorical predictor variables) contributing to reported SLs for four Vessel Types. Estimated SLs increased through ‘Electric’, ‘Skiff’, ‘Sailing’, ‘Monohull’, ‘RHIB’, ‘Catamaran’, ‘Fishing’, ‘Landing Craft’,’ Tug’, ‘Military’ to ‘Cargo’ Vessel Types, ranging between 130 and 195 dB re 1µPa m across all Vessel Types and &gt;29 dB range within individual Vessel Types. The most parsimonious model (22.7% deviance explained) included ‘Speed’ and ‘Closest Point of Approach’ (CPA) which displayed non-linear, though generally positive, relationships with SL. Similar to large vessels, regulation of speed can reduce SLs and vessel noise impacts (with consideration for additional exposure time from travelling at slower speeds). However, the relationship between speed and SLs in planing hull and semi-displacement vessels can be non-linear. The effect of CPA on estimated SL is likely a combination of propagation losses in the shallow study locations, often-neglected surface interactions, different methodologies, and that the louder Vessel Types were often recorded at greater CPAs. Significant effort is still required to fully understand SL variability, however, the International Standards Organisation’s highest reporting criteria for SLs requires water depths that often only occur offshore, beyond the safe operating range of small vessels. Additionally, accurate determination of monopole SLs in shallow water is complicated, requiring significant geophysical information along the signal path. We suggest the development of appropriate shallow-water criteria to complete these measurements using affected SLs and a comprehensive study including comparable deep- and shallow-water measures.

Design and analysis of a flat gain and linear low noise amplifier using modified current reused structure with feedforward structure

In this paper, a Low Noise Amplifier (LNA) with the current reused topology is proposed for wideband applications. To increase input impedance matching common source with inductive degeneration and RC shunt feedback structure is used. To extend the bandwidth, inductive series peaking technique is utilized. In the next stage, two parallel structure is hired to have a high voltage gain with low power consumption in addition to improve linearity. Also, by using the self-forward-body-bias (SFBB) technique, supply voltage is reduced and as a result power consumption is decreased further. The proposed LNA exhibits the high and flat gain of 14.7–15.4 ​dB, input return loss of less than −11 ​dB and noise figure range of 2.3–4.4 ​dB from 1 ​GHz up to 8 ​GHz. It consumes 5.4 ​mW from a 1.2 ​V power supply. The achieved IIP3 range for the proposed LNA is 0 ​dBm up to +2.7 ​dBm. The proposed LNA occupies 0.45 ​mm2 in 0.18-μm CMOS technology.

A high gain and compact transmitarray antenna for Ku-band satellite communications

ABSTRACT This work focuses on designing a low-profile frequency selective surface transmitarray antenna at 12 GHz using a four-layer Split Ring Resonator structure. The parametric analysis shows a high transmission coefficient magnitude of −2.38 dB and 349-degrees phase range. X-band horn antenna is used as a feed source to illuminate the Frequency Selective Surface (FSS) transmitarray layers. Each FSS layer is comprised of 121 elements. The measured results show a wide impedance bandwidth of 35%, a high gain value of 21.9 dBi and 11.6% 1-dB bandwidth. The proposed design can be used in high gain array antenna applications, particularly Ku band Satellite communication systems.

Transmastoid Superior Semicircular Canal Plugging: A Prospective Analysis of Surgical Outcomes.

To assess the outcomes of the transmastoid superior semicircular canal plugging in patients with superior semicircular canal dehiscence (SSCD). Prospective cohort study. Tertiary, university center. Patients with SSCD undergoing transmastoid superior semicircular canal plugging within a 30-month period. Transmastoid superior semicircular canal occlusion. We documented the surgical technique, pre- and postoperative (3-month review) dizziness handicap inventory scores, average hearing thresholds, low-frequency air-bone gap, six-canal video head-impulse-test responses, improvement of the auditory symptoms and complications. Out of 30 patients with SSCD, 11 patients (12 ears) were enrolled with an average age 41.17 years (range 32-65 years). Oscillopsia resolved in all patients; DHI score improved from 56.7 (range 22-84) preoperatively to 25.83 (10-46) postoperatively (p = 0.001), while out of the nine patients with troublesome auditory symptoms, five patients noticed an improvement. The average pre- and postoperative hearing thresholds were 15.2 dB (range 3-32.5 dB) and 14.17 dB (range 5-30 dB) (p = 0.73), respectively. The average pre- and postoperative low-frequency air bone gap was 12.3 dB (range 5-20 dB) and 9.4 dB (range 0-20 dB), respectively (p = 0.24) (Table 1). There were no major complications; two patients developed postoperative benign paroxysmal positional vertigo. Transmastoid plugging of the superior semicircular canal can safely and significantly improve the vestibular symptoms of the patients with SCDS, as well as the auditory symptoms in a substantial number of patients in a hearing-preservation way.

Intraoperative navigation during atresiaplasty for congenital aural atresia

ObjectiveThe purpose of this study was to evaluate the feasibility of intraoperative navigation (ION) using adhesive fiducials and high-resolution computed tomography (HRCT) of the temporal bone in pediatric patients undergoing atresiaplasty for congenital aural atresia (CAA). MethodsFrom June 2018 to August 2019, a retrospective review was performed on pediatric patients with unilateral or bilateral CAA who underwent atresiaplasty with or without concurrent bone anchored implant (BAI) placement. Single stage atresiaplasty was performed at a tertiary referral center with ION linked to image-guidance compatible HRCT non-contrast temporal bone images. Up to six adhesive fiducials were placed for navigation. Patient demographics were collected including Schuknecht classification type and Jahrsdoerfer score. Main outcome measures included the number of useable adhesive fiducials for navigation, navigation system registration accuracy, operative time, intraoperative complications, and postoperative outcomes including facial nerve function, surgical site infection rate, restenosis rate, and audiometric data. ResultsFive patients (3 male, 1 AU atresia, 2 AS atresia, all Schuknecht type C) with an average age of 9.2 years (range 6.8–11.8 years) underwent single sided atresiaplasty with ION. Two patients underwent concurrent BAI placement. Average Jahrsdoerfer score was 8.6 (range 7–10). Preoperative audiogram demonstrated a mean air-bone gap (ABG) of 45 dB (range 35–54 dB). The navigation system registration accuracy ranged from 0.08 to 1.80 mm (mean 1.00 mm). Mean operative time was 268 min (range 217–307 min). There were no intraoperative complications. At an average follow up of 7.2 months (range 2–15 months), postoperative facial nerve function was normal in all patients and no patients developed postoperative stenosis or surgical site infections. Four patients underwent postoperative audiogram at an average of 4 months after surgery (range 2–5 months) and all demonstrated an ABG of less than 30 dB (mean 20 dB, range 15–26 dB) with an average improvement in ABG of 23 dB (range 11–39 dB). The one patient who did not undergo postoperative pure tone audiometry underwent AzBio speech perception testing and demonstrated an improvement from 81% to 89%. ConclusionsThe use of ION in otologic surgery is uncommon. Inherent aberrant temporal bone anatomy in CAA makes this a unique population to study the value of this technology. The use of adhesive fiducials is feasible, with navigation registration accuracy and surgical outcomes comparable to those in the literature. More data is necessary regarding the impact of ION on long-term surgical and audiometric outcomes.

Tunable bandpass filter using double resistive feedback floating active inductor for 5 GHz wireless LAN Applications

It has been a challenging task for the designers to implement on-chip bandpass filter at high frequency with better performance. In this paper, a tunable RF bandpass filter using double resistive feedback floating active inductor (AI) based on gyrator-C topology has been proposed using 40 nm CMOS technology for 5 GHz WLAN applications. Small signal analytical modelling determines the design parameters affecting the performance of proposed floating AI, which ascertains that the double resistive feedback increases the quality factor as well as inductance value. The proposed AI attains a maximum quality factor of 964, high inductance ranging from 420 to 2080 nH and wide inductive bandwidth varying from 550 MHz to 7.85 GHz. Total current drawn by the AI is 2.66 mA at 1.2 V power supply and occupies an area of 17.1 × 9.1 µm2. In order to validate the performance of AI, a second-order tunable bandpass filter with frequency range 5.15–5.35 GHz has been implemented, with a small fractional 3-dB bandwidth, quality factor and 1-dB compression point of 15 MHz, 346 and − 2.8 dBm respectively. The Bandpass filter attains the figure of merit of 92.16 dB and dynamic range of 150 dB-Hz.

Variability and Power to Detect Progression of Different Visual Field Patterns

To compare the variability and ability to detect visual field (VF) progression of 24-2, central 12 locations of the 24-2 and 10-2 VF tests in eyes with abnormal VFs. Retrospective, multisite cohort. A total of 52 806 24-2 and 11 966 10-2 VF tests from 7307 eyes from the Glaucoma Research Network database were analyzed. Only eyes with ≥ 5 visits and ≥ 2 years of follow-up were included. Linear regression models were used to calculate the rates of mean deviation (MD) change (slopes), whereas their residuals were used to assess variability across the entire MD range. Computer simulations (n= 10 000) based on real MD residuals of our sample were performed to estimate power to detect significant progression (P < 5%) at various rates of MD change. Time required to detect progression. For all 3 patterns, the MD variability was highest within the-5 to-20 decibel (dB) range and consistently lower with the 10-2 compared with 24-2 or central 24-2. Overall, time to detect confirmed significant progression at 80% power was the lowest with 10-2 VF, with a decrease of 14.6% to 18.5% when compared with 24-2 and a decrease of 22.9% to 26.5% when compared with central 24-2. Time to detect central VF progression was reduced with 10-2 MD compared with 24-2 and C24-2 MD in glaucoma eyes in this large dataset, in part because 10-2 tests had lower variability. These findings contribute to current evidence of the potential value of 10-2 testing in the clinical management of patients with glaucoma and in clinical trial design.

A Novel Pseudo-Taylor-Exponential Approximation Technique for Input–Output Range Extension with Reduced Linearity Error and its Current-Mode CMOS Implementation

A novel mathematical approach has been proposed for input–output range extension of Pseudo-Taylor-Exponential-Approximation (PTEA) for achieving over seven-decade exponential function, while reducing the linearity error by 1 dB and attaining simple coefficients such as to realize this technique in designing the MOSFET based circuit. This new MPTEA technique, has been successfully utilized for its current-mode (I-I) CMOS implementation involving translinear principle of MOSFETs in weak inversion (WI) region. The CMOS synthesis procedure has been detailed and relevant second-order effects consists of noise, bulk-effect etc. have been explored. For post-layout simulations of the synthesized CMOS implementation, the SPECTRE simulation tool from Cadence, with 180 nM CMOS parameters, has been utilized to justify its practical workability. The proposition, in its CMOS layout, occupies an area of 0.0126mm2 only. It consumes only ≈4.92 μW static power by utilizing ± 0.65 V power supply and produces 146.5 dB range of linear-in-dB output with ± 1 dB linearity error.

Volumetric Quantification of Flash Flood Using Microwave Data on a Watershed Scale in Arid Environments, Saudi Arabia

Actual flood mapping and quantification in an area provide valuable information for the stakeholder to prevent future losses. This study presents the actual flash flood quantification in Al-Lith Watershed, Saudi Arabia. The study is divided into two steps: first is actual flood mapping using remote sensing data, and the second is the flood volume calculation. Two Sentinel-1 images are processed to map the actual flood, i.e., image from 25 May 2018 (dry condition), and 24 November 2018 (peak flood condition). SNAP software is used for the flood mapping step. During SNAP processing, selecting the backscatter data representing the actual flood in an arid region is challenging. The dB range value from 7.23–14.22 is believed to represent the flood. In GIS software, the flood map result is converted into polygon to define the flood boundary. The flood boundary that is overlaid with Digital Elevation Map (DEM) is filled with the same elevation value. The Focal Statistics neighborhood method with three iterations is used to generate the flood surface elevation inside the flood boundary. The raster contains depth information is derived by subtraction of the flood surface elevation with DEM. Several steps are carried out to minimize the overcalculation outside the flood boundary. The flood volume can be derived by the multiplication of flood depth points with each cell size area. The flash flood volume in Al-Lith Watershed on 24 November 2018 is 155,507,439 m3. Validity checks are performed by comparing it with other studies, and the result shows that the number is reliable.

Generation of four-wave mixing in molybdenum ditelluride (MoTe2)-deposited side-polished fibre

In this work, we report the effect of four-wave mixing (FWM) in MoTe2 deposited on a side-polished fibre (SPF). The MoTe2 layer has a nonlinear coefficient of 17.368 W−1 km−1 at 1550 nm, while the coated SPF has a conversion efficiency of – 38 dB and output tuning range of 5 nm. The generated idlers from the induced FWM effect were observed to be highly stable with minimal peak fluctuations and only minor changes in their measured conversion efficiency. The proposed MoTe2 based SPF is thus a suitable device for inducing the FWM effect in an optical fibre laser cavity and could also serve to induce other non-linear optical effects for use in optical communications networks.

Adaptation of the Standardized Hearing Outcomes Scattergram to Hearing Preservation in Cochlear Implantation.

Encourage adaptation of a standardized format for reporting hearing preservation outcomes in cochlear implantation (CI). Retrospective chart review. Tertiary referral center. One hundred seventy-eight postlingually deafened adults with bilateral SNHL and a preoperative low-frequency pure-tone average (LFPTA) 80 dB HL or better at 125, 250, and 500 Hz in the ear to be implanted. Subjects underwent unilateral CI from 2013 to 2019 at a large referral center. Pre- versus postoperative LPFTA was used to generate a scattergram. Pre- versus postoperative activation LPFTA, percentage of patients fit with electric and acoustic stimulation, scattergram plot. Average postoperative LFPTA was 68.6 dB HL (range 18-68) compared with 48.7 dB (range 5-80), preoperatively. At activation, the average LFPTA shift at CI activation was 20.5 dB HL (range 0-60) and 83.5% (n = 137) patients had hearing preserved, of whom 41.6% were fit with electric and acoustic stimulation throughout the study period. The scattergram successfully illustrates the distribution and number of patients with their respective audiometric outcomes. The scattergram developed for reporting hearing outcomes in clinical trials is highly adaptable to reporting hearing preservation results in cochlear implant surgery. It represents a transparent and accessible option for reporting outcomes that can be used as a consistent format to allow for interstudy comparison and future meta-analysis.