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Mating behaviors are sensitive to novel or stressful thermal conditions, particularly for ectothermic organisms. An organism's sensitivity to temperature, which may manifest in altered mating outcomes, can be shaped in part by temperatures experienced during development. Here, we tested how developmental temperature shapes the expression of adult mating-related behaviors across different ambient conditions, with a focus on courtship behavior, mating rates, and mating signals and preferences. To do so, we reared treehoppers under two temperature regimes and then tested the expression of male and female mating behaviors across a range of ambient temperatures. We found that developmental temperature affects the thermal sensitivity of courtship behavior and mating signals for males. However, developmental temperature did not affect the thermal sensitivity of courtship or mate preferences in females. This sex-specific plasticity did not alter the likelihood of mating across ambient temperatures, but it did disrupt how closely mating signals and preferences matched each other at higher ambient temperatures. As a result, developmental temperature could alter sexual selection through signal–preference de-coupling. We further discuss how adult age may drive sex-specific results, and the potential for mismatches between developmental and mating thermal environments under future climate change predictions. [ABSTRACT FROM AUTHOR]

Seismic‐acoustic wavefield propagations on synthetic 2D models formed by different structural backgrounds are analysed in four test cases. These test cases were carried out employing staggered‐grid finite differences and absorbing boundaries of the convolutional perfectly matched layers type, which allowed analysing in a time of 7.0 s: (a) the seismic‐acoustic wavefield behaviour, (b) the kinetic seismic energy flux and potential seismic energy flux and (c) the energy differences (ΔKEF/ΔPEF) due to each type of proposed structure. In the first two test cases, a relationship was observed between average kinetic seismic energy flux/potential seismic energy flux values and the different structural densities ε of each synthetic model, which were formed by a similar type of structure (fractures). The average kinetic seismic energy flux values increased when ε decreased, whereas the average potential seismic energy flux values decreased when ε also decreased. The largest ΔKEF/ΔPEF values were observed for those models with more structures, reaching up to 0.2 × 108/0.21 × 108 J/m2 in the first test case and up to 1.95 × 108/1.91 × 108 J/m2 in the second test case. Meanwhile, for those models with less number of structures was 0.04 × 108/0 J/m2 in test case 1 and 0.26 × 108/0.61 × 108 J/m2 in test case 2. In the third test case, a relationship was observed between the average potential seismic energy flux values and the ε values, but not with the average kinetic seismic energy flux values, the synthetic models of which were formed by different types of structures (lobes and fractures under different shapes and sizes). The kinetic seismic energy fluxes were more affected by structures closer to each other than by those further apart. Meanwhile, the potential seismic energy fluxes were more affected by larger structures, maintaining a relationship with the seismic frequency and wavelength. The largest ΔKEF/ΔPEF values reached up to 3.42 × 108/3.24 × 108 J/m2 in model with the highest ε value, whereas up to 0.49 × 108/0.67 × 108 J/m2 in the model with the lowest ε value. In the fourth test case, similar types of structures (fractures) were analysed under different orientations in each model. The kinetic seismic energy fluxes/potential seismic energy fluxes were higher in the model formed by better‐oriented structures or parallel with respect to the propagation direction of the seismic‐acoustic wavefield. These energy differences between each test case show how not only the number of structures in a model and the ε values influenced the seismic‐acoustic wavefield and the kinetic seismic energy flux/potential seismic energy flux, but also the structural aspects, the intrinsic elastic properties (e.g. the density used in structures), location (separation between structures) and orientation of structures. [ABSTRACT FROM AUTHOR]

Mormoopids are a small group of insectivorous bats largely distributed from the southwestern United States throughout Central and South America. They occupy a wide variety of habitats, and in Brazil have usually been associated with habitats in the Amazon, Cerrado, or Caatinga biomes. Nevertheless, most of the information compiled so far to infer their distributional limits is based on roosting colonies occasionally found in caves or on inventories using bat mist netting, which is known to be an ineffective method for capturing aerial insectivorous bats. In this contribution, we present new occurrence records of mormoopid bats based on acoustic surveys in the Caatinga and Cerrado biomes and make an extensive literature review to provide an up-to-date distribution of these bats in Brazil. We additionally describe important parameters of the echolocation calls of mormoopids across the geographical scope of our study, contrasting our data with published information to provide a better overview of the intraspecific acoustic variation of these bat species. Our acoustic data reveal a larger area of occurrence of mormoopids in Brazil than previously known, confirming new records for two states. [ABSTRACT FROM AUTHOR]

Fiberboards from scrap denim were fabricated using two different resins, melamine urea formaldehyde (MUF) and polymeric methylene diphenyl diisocyanate (pMDI). Resin content and MUF-pMDI weight ratio were studied. Physical and mechanical tests determined the modulus of elasticity (MOE), modulus of rupture (MOR), internal bond (IB), thickness swell (TS), and water absorption (WA). The resin content had significant impact on all properties. The MOE and IB were affected by the MUF-pMDI ratio. With 17 wt% more pMDI resin portion in the core layer of the denim boards, the IB for the denim fiberboard with a resin content of 15% was enhanced by 306%, while by 205% for the resin content of 25%. The increase in pMDI portion in the core layer of the boards improved both TS and WA of the scrap denim fiberboard. Effective bulk modulus elastography (EBME) was used to measure the acoustic reflection for the estimation of the strength properties of the denim fiberboard. The modulus results from EBME were correlated to the MOR, MOE, and IB of the denim fiberboard. A high correlation was found between the modulus from EBME and IB (R2 > 0.98). EBME can be a great technique to evaluate the bulk modulus distribution of the composites. [ABSTRACT FROM AUTHOR]

Background: A rare type of risk associated with firefighting activities and affecting the central nervous system (CNS) is acoustic trauma. The main causes of acoustic trauma in professional firefighters include long-term exposure to noise from fire engine sirens, emergency call alarms in the fire stations (fire halls), and the operation of equipment used during rescue and firefighting operations. Material/Methods: The study was based on an analysis of data obtained from the HR Department of the National Headquarters of the State Fire Service (NHSFS). The analysis included cases of acoustic trauma suffered by firefighters while on duty, which were reported to the control room of their firefighting units as rescuer accidents, and followed up with medical interventions. Results: The average number of accidents among SFS firefighters per year during the study period was n=1.617.During the study period (2015-2022), there were seven incidents in which a total of 11 firefighters suffered acoustic trauma affecting the CNS and the organ of hearing. Conclusions: To prevent on-duty accidents, both practical and theoretical training sessions are provided, covering measures aimed at reducing accident rates to minimum levels. Other important activities include hearing prophylaxis; medical examinations; breaks during work, appropriate organisation of work and the working environment; compliance with the applicable regulations, internal procedures and safety instructions; the use of personal protective equipment, and the good technical condition of vehicles and equipment. [ABSTRACT FROM AUTHOR]

The complex and highly tortuous microstructure of aerogels has led to the superior insulating capabilities that aerogels are known for. This open cell microstructure has also created a unique acoustic fingerprint that can be manipulated to achieve maximum acoustic insulation/absorption. The goal of this work was to create a computational approach for predicting sound propagation behavior in monolithic aerogels using the wave solving tool k-wave. The model presented here explores attenuation and loss values as a function of density, angle of incidence of wave, and medium (aqueous and non-aqueous) for frequencies in the range of 0.5–1 MHz. High numerical accuracy without a significant computational demand was achieved. Results indicate that loss increases as a function of frequency and the medium that the incoming wave is travelling through dominates the attenuation, loss, and other characteristics more than angle of incidence, and pore structure. [ABSTRACT FROM AUTHOR]

Marine Geological Institute acquired high-resolution seismic and acoustic data during a survey in the Waipoga Trough-West Papua in 2018. The profiles show acoustically blanking, turbid, and cloudy occur along the trough floor over 3,000 km2. Many accoustic chimneys are breaking through the seabed of recent and subrecent sediment layers. It is suggested due to the local expulsion of methane gas. The pockmarks occur as transparent and turbid acoustic characteristics. They locally have relief down to 2-10 m below the seafloor with horizontal dimensions up to 25 -100 m in width. Methane formation due to the rapid deposition of organic-rich sediment down the uplifted area around the trough, associated with thrust fold tectonics is suggested as a triggering agent for the acoustic anomaly formation. [ABSTRACT FROM AUTHOR]

Air multiplier fans, which are produced as an alternative to the convectional propellers used today, have come into prominence with the advantages providing in both efficiency and usage. In this study, three different blade profiles based on NACA 0012, NACA 1408, and EPPLER 1214 were used in the fan body. The design based on the NACA 0012 of body profile provided the highest flow rate. This profile was optimized using CFD analysis according to seven different geometrical parameters determined as the angle of attack, width, length, gap, inner and outer diameters, and tail length. The profile that provides less noise against the highest flow rate was determined as the optimal design. With CFD analysis, the sound pressure level of the optimal design was calculated by the k-ω and LES method, and the results were compared with each other. [ABSTRACT FROM AUTHOR]

Foraging animals must contend with fluctuating environmental variables that affect foraging success, including conditions like wind noise, which could diminish the usefulness of particular sensory modes. Although the documented impact of anthropogenic noise on animal behavior has become clear, there is limited research on natural noise and its potential influence on mammalian behavior. We investigated foraging behavior in the myrmecophagous bat-eared fox (Otocyon megalotis), a species known to rely predominantly on hearing for prey detection. For a year, we monitored the foraging behavior of 18 bat-eared foxes from a habituated population in South Africa, amidst varying wind speeds (0–15.5 km/h). In contrast to expectations, foraging rates did not generally decline with increasing wind speed, except for foraging rate outside termite patches in fall. Furthermore, wind speed had little correlation with time spent in patches. In winter, however, we observed an increase in foraging rate with increasing wind speed both within and outside patches. At the observed wind speeds, these acoustically driven insectivores continue to forage effectively despite potentially distracting or masking noises. With anthropogenic noise producing sound across a broader frequency range, it is important to examine the responses of these canids to artificial sources of acoustic disturbance as well. [ABSTRACT FROM AUTHOR]

The acoustic analysis helps to discriminate emotions according to non-verbal information, while linguistics aims to capture verbal information from written sources. Acoustic and linguistic analyses can be addressed for different applications, where information related to emotions, mood, or affect are involved. The Arousal-Valence plane is commonly used to model emotional states in a multidimensional space. This study proposes a methodology focused on modeling the user’s state based on the Arousal-Valence plane in different scenarios. Acoustic and linguistic information are used as input to feed different deep learning architectures mainly based on convolutional and recurrent neural networks, which are trained to model the Arousal-Valence plane. The proposed approach is used for the evaluation of customer satisfaction in call-centers and for health-care applications in the assessment of depression in Parkinson’s disease and the discrimination of Alzheimer’s disease. F-scores of up to 0.89 are obtained for customer satisfaction, of up to 0.82 for depression in Parkinson’s patients, and of up to 0.80 for Alzheimer’s patients. The proposed approach confirms that there is information embedded in the Arousal-Valence plane that can be used for different purposes. [ABSTRACT FROM AUTHOR]

Codling moth (CM) is a major apple pest. Current manual method of detection is not very effective. The development of nondestructive monitoring and detection methods has the potential to reduce postharvest losses from CM infestation. Previous work from our group demonstrated the effectiveness of hyperspectral imaging (HSI) and acoustic methods as suitable techniques for nondestructive CM infestation detection and classification in apples. However, both have limitations that can be addressed by the strengths of the other. For example, acoustic methods are incapable of detecting external CM symptoms but can determine internal pest activities and morphological damage, whereas HSI is only capable of detecting the changes and damage to apple surfaces and up to a few mm inward; it cannot detect live CM activity in apples. This study investigated the possibility of sensor data fusion from HSI and acoustic signals to improve the detection of CM infestation in apples. The time and frequency domain acoustic features were combined with the spectral features obtained from the HSI, and various classification models were applied. The results showed that sensor data fusion using selected combined features (mid-level) from the sensor data and three apple varieties gave a high classification rate in terms of performance and reduced the model complexity with an accuracy up to 94% using the AdaBoost classifier, when only six acoustic and six HSI features were applied. This result affirms that the sensor fusion technique can improve CM infestation detection in pome fruits such as apples. [ABSTRACT FROM AUTHOR]

Herein, the Helmholtz resonance modes design is developed obtaining Fano‐like interferences. The proposed design employs two vertically aligned Helmholtz resonators exciting two different orders of mode, which induce desired constructive or destructive interferences. The critical part of this design is the realization of a mode‐selective feature. The mode‐selective feature is achieved by adjusting the geometrical parameters of the two Helmholtz resonators. Meanwhile, it can be constructed by applying different mediums under the symmetrical geometric topology. From the numerical simulation results, desired modes can be excited at desired resonant frequencies achieving constructive or destructive interferences. These Fano‐like phenomena are also confirmed by experimental results. [ABSTRACT FROM AUTHOR]

Detection, classification, and localization (DCL) techniques are being developed around the use of a phase-measuring sidescan sonar (PMSS) in very shallow waters. The instrument simultaneously collects co-located sidescan imagery and bathymetry in extreme shallow water environments (<1 m water depth). In addition to the bathymetry, an uncalibrated backscatter data set, referred to in this study as phase-measured, bathymetry-mode backscatter (BMB), is also collected. This BMB has been minimally addressed in the literature. This work aims to use the BMB to detect and differentiate between various objects on the seafloor, including unexploded ordnance (UXO), and placed marine debris, or 'clutter', such as lobster pots, boat propellers, and car tires. The differentiation from multiple seafloor types including mud, sand, and gravel and different types of objects occurred through various statistical analysis methods including binomial and multinomial logistic regression. These methods have been applied to create statistical regression models for several variables including phase-measured, bathymetry-mode backscatter amplitude, sounding distance from nadir, per-ping vessel roll, orientation offset between per-ping vessel heading and object orientation, and all combinations of these variables. These statistical tests produced maximum likelihood odds ratios of individual soundings being associated with the various seafloor and object types. Results from these analyses shows that DCL could be possible with phase-measured, bathymetry-mode backscatter from this PMSS system, though these results may not be representative for all bed types and phase-measuring systems. [ABSTRACT FROM AUTHOR]

The acoustic monitoring, omni-directional system (AMOS) in the Galileo Project is a passive, multi-band, field microphone suite designed to aid in the detection and characterization of aerial phenomena. Acoustic monitoring augments the Project's electromagnetic sensors suite by providing a relatively independent physical signal modality with which to validate the identification of known phenomena and to more fully characterize detected objects. The AMOS system spans infrasonic frequencies down to 0.05 Hz, all of audible, and ultrasonic frequencies up to 190 kHz. It uses three distinct systems with overlapping bandwidths: infrasonic (0.05 Hz – 20 Hz), audible (10 Hz – 20 kHz), and ultrasonic (16 kHz – 190 kHz). The sensors and their capture devices allow AMOS to monitor and characterize the tremendous range of sounds produced by natural and human-made aerial phenomena, and to encompass possible acoustic characteristics of novel sources. Sound signals from aerial objects can be captured and classified with a single microphone under the following conditions: the sound reaches the sensor; the sound level is above ambient noise; and the signal has not been excessively distorted by the transmission path. A preliminary examination of the signal and noise environment required for the detection and characterization of aerial objects, based on theoretical and empirical equations for sound attenuation in air, finds that moderately loud audible sources (100 dB) at 1 km are detectable, especially for frequencies below 1 kHz and in quiet, rural environments. Infrasonic sources are detectable at much longer distances and ultrasonic at much shorter distances. Preliminary aircraft recordings collected using the single, omni-directional audible microphone are presented, along with basic spectral analysis. Such data will be used in conjunction with flight transponder data to develop algorithms and corresponding software for quickly identifying known aircraft and characterizing the sound transmission path. Future work will include multi-sensor audible and infrasonic arrays for sound localization; analysis of larger and more diverse data sets; and exploration of machine learning and artificial intelligence integration for the detection and identification of many more types of known phenomena in all three frequency bands. [ABSTRACT FROM AUTHOR]

The dilution of undesired and vandalize noise to a sustainable level is the subject of continuing research in the fields of applied mathematics, physics, and engineering. Therefore, the present study investigates the mechanism of an acoustic wave scattering, which includes the force propagation due to the incidence through region R1$$ {R}_1 $$ of elastic boundary condition. Both planar and nonplanar surfaces are allowed in this waveguide configuration. In this structure, the scattered fields in the regions of the inner surfaces are acoustically rigid and satisfy the standard orthogonality relation, while the fields on the upper outer surfaces are flexural nature that can be tackled using modified orthogonality relation. Thus, we intend to simultaneously take into account the behavior of the scattered field in both planar and nonplanar zones. Solving nonorthogonal eigenfunctions required the development of a modified orthogonality relation. Modified orthogonal relation and the mode‐matching (MM) technique have combined to get the solution of proposed model. The last section graphically discusses the solution for various frequencies and heights to observe the scattering behavior in all regions of the duct. In accordance with different characteristics of the waveguide material, expressions for the distribution of powers in different parts of the channel are developed and schematically depicted. A variety of mathematical and physical justifications provide strong support to results. [ABSTRACT FROM AUTHOR]

Objective: The perfusion profile of vestibular schwannomas (VSs) and the factors that influence it have yet to be determined. Materials and Methods: Twenty patients with sporadic VS were analyzed by calculating parameters related to the extravascular extracellular space (EES)--the volume transfer constant between a vessel and the EES (Ktrans); the EES volume per unit of tissue volume (Ve); and the rate transfer constant between EES and blood plasma (Kep)--as well as the relative cerebral blood volume (rCBV), and by correlating those parameters with the size of the tumor and its structure (solid, cystic, or heterogeneous). Results: Although Ktrans, Ve, and Kep were measurable in all tumors, rCBV was measurable only in large tumors. We detected a positive correlation between Ktrans and rCBV (r = 0.62, p = 0.031), a negative correlation between Ve and Kep (r = --0.51, p = 0.021), and a positive correlation between Ktrans and Ve only in solid VSs (r = 0.64, p = 0.048). Comparing the means for small and large VSs, we found that the former showed lower Ktrans (0.13 vs. 0.029, p < 0.001), higher Kep (0.68 vs. 0.46, p = 0.037), and lower Ve (0.45 vs. 0.83, p < 0.001). The mean Ktrans was lower in the cystic portions of cystic VSs than in their solid portions (0.14 vs. 0.32, p < 0.001), as was the mean Ve (0.37 vs. 0.78, p < 0.001). There were positive correlations between the solid and cystic portions for Ktrans (r = 0.71, p = 0.048) and Kep (r = 0.74, p = 0.037). Conclusion: In VS, tumor size appears to be consistently associated with perfusion values. In cystic VS, the cystic portions seem to have lower Ktrans and Ve than do the solid portions. [ABSTRACT FROM AUTHOR]

The use of acoustic methods for failure detection is increasing in recent times. By using the acoustic method, some features related to the condition of the equipment under test can also be extracted. The main objective of this study was to compare the effect of using filters and augmentation on audio signals in the data training process on the accuracy and loss generated during training and testing. The model is developed using an artificial neural network. The MIMII dataset, which can be accessed openly, is being used for training and testing purposes. Based on the four scenarios designed, it can be seen that the movement of changes in accuracy values in tests involving the use of original data and augmented data is faster (close to 100% after the twentieth epoch) than the other methods. This is because the augmentation process in the form of a time shift does not change the signal in the frequency domain. Moreover, the test signal used is a periodic signal. [ABSTRACT FROM AUTHOR]

This study visualises the mode of the vibration of kulintangan using Electronic Speckle Pattern Interferometry (ESPI) to reveal the modes. It was found that the production of sound by the kulintangan was dominated by a particular mode which may be the (0,1), (1,1), (2,2), (3,2), and (4,2) of free edge circular gong. The spectrum distribution from the strike on the kulintangan showed it. The small gong A-H has an approximately harmonic spectrum with a fundamental frequency of 1240, 1055, 934, 792, 705, 624, 474, and 422 Hz. The gong does not display a similar occurrence of harmonics due to the ruggedness of the surface texture of the gong. This finding can be of great importance to facilitate a better understanding of the mechanisms involved in the sound production of musical instruments. Our research is visualising the sound sonically through PicoScope oscilloscopes and ESPI. [ABSTRACT FROM AUTHOR]

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A nonconventional material with remarkable thermal and acoustic insulation properties from aerogels category was experimentally made. Produced from a recycled commercial waste (polyethylene terephthalate-PET) and an industrial by-product (fly ash) as well as a biomaterial (psyllium husk) used for the first time as a binder by mixing with water, the aerogel was subjected to a freeze-drying process. The determination of the product characteristics highlighted extremely low densities (0.022-0.041 g· cm-3), very low thermal conductivities (0.035-0.037 W·m-1·K-1), very high porosities (97.8-98.5 %), mechanical properties superior to those of an unreinforced gel (compression strength of 9.5-16.4 kPa and Young's modulus of 4.15-18.93 kPa), and excellent noise absorption properties (noise reduction coefficient of 0.30-0.33). The manufacturing process of this inexpensive product allows for a clean environment. [ABSTRACT FROM AUTHOR]

Photoacoustic flow cytometry is a method to detect rare analytes in fluids. We developed photoacoustic flow cytometry to detect pathological cells in body fluids, such as circulating tumor cells or bacteria in blood. In order to induce specific optical absorption in bacteria, we use modified bacteriophage that precisely target bacterial species or subspecies for rapid identification. In order to reduce detection variability and to halt the lytic lifescycle that results in lysis of the bacteria, we attached dyed latex microspheres to the tail fibers of bacteriophage that retained the bacterial recognition binding sites. We tested these microsphere complexes using Salmonella enterica (Salmonella) and Escherichia coli (E. coli) bacteria and found robust and specific detection of targeted bacteria. In our work we used LT2, a strain of Salmonella, against K12, a strain of E. coli. Using Det7, a bacteriophage that binds to LT2 and not to K12, we detected an average of 109.3 ± 9.0 of LT2 versus 2.0 ± 1.7 of K12 using red microspheres and 86.7 ± 13.2 of LT2 versus 0.3 ± 0.6 of K12 using blue microspheres. These results confirmed our ability to selectively detect bacterial species using photoacoustic flow cytometry. [ABSTRACT FROM AUTHOR]

Objective: This study assessed the use of Aloe vera lotion as an alternative coupling medium for ultrasound imaging. Materials and Methods: A prospective analytical research design was adopted. A total of 50 subjects who consented were randomly recruited into the study from the University of Calabar Teaching Hospital (UCTH), Calabar and the Gijuwie Medical Diagnostics, Calabar. A total of 50 image pairs were obtained on scanning with Aloe vera lotion (Image A) and commercial ultrasound gel (Image B) for comparison. Image quality was assessed using anatomical details (AD) and visualization of hyperechoic structures (VHS) as criteria. Results: A substantial agreement was seen among raters (A: k = 0.658, B = 0.691; P <.05) with acceptable level of consistency (Cronbach's alpha scores of 0.701 and 0.825 for Aloe vera lotion and commercial gel, respectively) based on AD. Images recommended as acceptable by raters was 91.7% for Aloe vera lotion and 81.7% for commercial gel. Both methods demonstrated almost perfect agreement (kappa > 80; P <.05) with each other based on AD and VHS (Table 3). Conclusion: Aloe vera lotion, which is locally available and relatively affordable, has the potential to be used as acoustic coupling medium in diagnostic sonography. [ABSTRACT FROM AUTHOR]

The on-board components mounted on the structural panel of spacecraft are exposed to a severe random vibration environment, mainly induced by the acoustic excitation of the panel structure due to the large acoustic noise from the launch vehicle. To verify the components' resistance against the vibrational environment, random vibration tests of the components are generally performed at the excitation level based on vibroacoustic prediction. In order to consider the prediction uncertainty, there actually needs to add a margin, which often poses an excess of design and testing. JAXA has been involved with predicting wide frequency band vibro-acoustic behavior of the structural panel using SEA (Statistical Energy Analysis), in which we have to add margin to take into account spatial and frequency bandwidth uncertainties. These kinds of uncertainty margin may result in over conservative margin and causes costly over conservative design. To reduce the over conservative margin in SEA method, in this paper, a wavenumber expression of joint acceptance method calculated by fast Fourier transform approach on finite element model parameter of panel, i.e., mode frequency and mode shape is proposed. The proposed method is applied to two structural panels of actual spacecraft and compared with acoustic test results. It is shown by comparison with the test result of an actual panel that the proposed method achieved less conservative prediction in each individual component mounting location rather than enveloping every mounting location that SEA calculates.

BackgroundVery few studies have assessed the presence of a possible correlation between speech variables and limb bradykinesia in patients with Parkinson's disease (PD). The objective of this study was to find correlations between different speech variables and upper extremity bradykinesia under different medication conditions in advanced PD patients.MethodsRetrospective data were collected from a cohort of advanced PD patients before and after an acute levodopa challenge. Each patient was assessed with a perceptual-acoustic analysis of speech, which included several quantitative parameters [i.e., maximum phonation time (MPT) and intensity (dB)]; the Unified Parkinson's Disease Rating Scale (UPDRS) (total scores, subscores, and items); and a timed test (a tapping test for 20 s) to quantify upper extremity bradykinesia. Pearson's correlation coefficient was applied to find correlations between the different speech variables and the tapping rate.ResultsA total of 53 PD patients [men: 34; disease duration: 10.66 (SD 4.37) years; age at PD onset: 49.81 years (SD 6.12)] were included. Levodopa intake increased the MPT of sustained phonation (p < 0.01), but it reduced the speech rate (p = 0.05). In the defined-OFF condition, MPT of sustained phonation positively correlated with both bilateral mean (p = 0.044, r-value:0.299) and left (p = 0.033, r-value:0.314) tapping. In the defined-ON condition, the MPT correlated positively with bilateral mean tapping (p = 0.003), left tapping (p = 0.003), and right tapping (p = 0.008).ConclusionThis study confirms the presence of correlations between speech acoustic variables and upper extremity bradykinesia in advanced PD patients. These findings suggest common pathophysiological mechanisms.

High level of noise limits the reliability of the lubricated journal bearing. In the current paper, the possibility of bearing design with a heterogeneous rough/smooth surface is explored using the computational fluid dynamics (CFD) approach to improve tribological and acoustic performance. A parametric analysis is conducted to determine the optimal surface roughness level, the cavitation pressure, and the ratio of length to the diameter of the journal. The effect of the presence of a roughened pattern on the thermal behavior of the lubricant, friction force, noise level, and cavitation phenomena was also studied in depth. The main finding of the present study is that when conventional journal bearing fails in generating the load support for concentric conditions, the heterogeneous rough/smooth bearing has a beneficial effect by increasing the load-carrying capacity. Furthermore, the high level of surface roughness can significantly increase the load-carrying capacity while decreasing frictional forces and acoustic power. However, the roughness does not dramatically change the maximum temperature (less than 1%). The numerical results also suggest that the variation in vapor saturation pressure has a negligible effect on the maximum temperature, friction force, and noise level.

We demonstrate strongly collimated beam formation, at audible frequencies, in a three-dimensional acoustic phononic crystal where the wavelength is commensurate with the crystal elements; the crystal is a seemingly simple rectangular cuboid constructed from closely-spaced spheres, and yet demonstrates rich wave phenomena acting as a canonical three-dimensional metamaterial. We employ theory, numerical simulation and experiments to design and interpret this collimated beam phenomenon and use a crystal consisting of a finite rectangular cuboid array of $4\times 10\times 10$ polymer spheres 1.38 cm in diameter in air, arranged in a primitive cubic cell with the centre-to-centre spacing of the spheres, i.e. the pitch, as 1.5 cm. Collimation effects are observed in the time domain for chirps with central frequencies at 14.2 kHz and 18 kHz, and we deployed a laser feedback interferometer or Self-Mixing Interferometer – a recently proposed technique to observe complex acoustic fields—that enables experimental visualisation of the pressure field both within the crystal and outside of the crystal. Numerical exploration using a higher-order multi-scale finite element method designed for the rapid and detailed simulation of 3D wave physics further confirms these collimation effects and cross-validates with the experiments. Interpretation follows using High Frequency Homogenization and Bloch analysis whereby the different origin of the collimation at these two frequencies is revealed by markedly different isofrequency surfaces of the sonic crystal.

This research addresses the neglect of sensory features, specifically the soundscape, in studies focused on preserving historic areas. The aim was to contribute to soundscape research by examining the effect of sound on the perception of urban historical places and the impact of the “renewal and transformation” process on audio-visual experiences. This study focused on the historical Erbil Citadel as a case study area, known for its extensive cultural history. Sound sources in the region were identified, recorded, and analyzed using software to calculate the Sound Pressure Level (SPL). The sound sources assessed as a result of the analysis were examined using Schafer’s sound characteristics. In this study, data was collected through a soundwalk study in the historical Erbil Citadel, and its surroundings were identified. The characteristics of the sounds were determined from the sound recordings, enabling the distinction of sounds contributing to the city’s identity. A route was established in its current state, and it was identified which regional precautions should be taken to preserve the sound identity of the city.

This work involves exploring non-invasive sensor technologies for data collection and preprocessing, specifically focusing on novel thermal calibration methods and assessing low-cost infrared radiation sensors for facial temperature analysis. Additionally, it investigates innovative approaches to analyzing acoustic signals for quantifying coughing episodes. The research integrates diverse data capture technologies to analyze them collectively, considering their temporal evolution and physical attributes, aiming to extract statistically significant relationships among various variables for valuable insights. The study delineates two distinct aspects: cough detection employing a microphone and a neural network, and thermal sensors employing a calibration curve to refine their output values, reducing errors within a specified temperature range. Regarding control units, the initial implementation with an ESP32 transitioned to a Raspberry Pi model 3B+ due to neural network integration issues. A comprehensive testing is conducted for both fever and cough detection, ensuring robustness and accuracy in each scenario. The subsequent work involves practical experimentation and interoperability tests, validating the proof of concept for each system component. Furthermore, this work assesses the technical specifications of the prototype developed in the preceding tasks. Real-time testing is performed for each symptom to evaluate the system’s effectiveness. This research contributes to the advancement of non-invasive sensor technologies, with implications for healthcare applications such as remote health monitoring and early disease detection.

ObjectiveTo assess the risk recall of complications among patients who underwent different vestibular schwannoma (VS) treatments.Study designPatients with VS completed a voluntary and anonymous survey.SettingSurvey links were distributed via the Acoustic Neuroma Association (ANA) website, Facebook, and email list.Subjects and methodsSurveys were distributed to ANA members from January to March 2017. Of the 3200 ANA members with a VS diagnosis at the time of survey distribution, 789 (25%) completed the survey.ResultsSubjects reported the following incidence of posttreatment complications: imbalance (60%), hearing issues (51%), dry eyes (30%), headache (29%), and facial weakness (27%). Overall, 188 (25%) recalled remembering all the risks associated with their treatment. Among those in the surgical cohort (52%) who experienced balance issues, facial weakness, cerebrospinal fluid leak, meningitis, and stroke, 73%, 91%, 77%, 67%, and 33% claimed recall of these associated risks. Among those in the radiosurgery cohort (28%) who experienced balance issues, facial weakness, and hydrocephalus, 56%, 52%, and 60% recalled discussions of those risks. Patients with higher-level education (P = .026) and those who underwent surgery (P = .001) had a significantly higher risk recall ratio, while sex, age, and tumor size were not significant contributing factors.ConclusionNot all patients with VS who experienced treatment complications recalled remembering those risks being discussed with them. Patients with higher education and those who underwent surgery had a better recall of risks associated with different treatment modalities. The risk recall ratio of patients experiencing complications ranged 33% to 91%, suggesting an opportunity for decision-making and discussion improvement.

BackgroundNeurofibromatosis type 2 (NF2) is a genetic tumor-predisposition disorder caused by NF2/merlin tumor suppressor gene inactivation. The hallmark of NF2 is formation of bilateral vestibular schwannomas (VS). Because merlin modulates activity of the Ras/Raf/mitogen-activated protein kinase kinase (MEK)/extracellular signal-regulated kinase (ERK) pathway, we investigated repurposing drugs targeting MEK1 and/or MEK2 as a treatment for NF2-associated schwannomas.MethodsMouse and human merlin-deficient Schwann cell lines (MD-MSC/HSC) were screened against 6 MEK1/2 inhibitors. Efficacious drugs were tested in orthotopic allograft and NF2 transgenic mouse models. Pathway and proteome analyses were conducted. Drug efficacy was examined in primary human VS cells with NF2 mutations and correlated with DNA methylation patterns.ResultsTrametinib, PD0325901, and cobimetinib were most effective in reducing MD-MSC/HSC viability. Each decreased phosphorylated pERK1/2 and cyclin D1, increased p27, and induced caspase-3 cleavage in MD-MSCs. Proteomic analysis confirmed cell cycle arrest and activation of pro-apoptotic pathways in trametinib-treated MD-MSCs. The 3 inhibitors slowed allograft growth; however, decreased pERK1/2, cyclin D1, and Ki-67 levels were observed only in PD0325901 and cobimetinib-treated grafts. Tumor burden and average tumor size were reduced in trametinib-treated NF2 transgenic mice; however, tumors did not exhibit reduced pERK1/2 levels. Trametinib and PD0325901 modestly reduced viability of several primary human VS cell cultures with NF2 mutations. DNA methylation analysis of PD0325901-resistant versus -susceptible VS identified genes that could contribute to drug resistance.ConclusionMEK inhibitors exhibited differences in antitumor efficacy resistance in schwannoma models with possible emergence of trametinib resistance. The results support further investigation of MEK inhibitors in combination with other targeted drugs for NF2 schwannomas.

OBJECTIVES: To analyze medical malpractice lawsuit trends pertaining to cases of vestibular schwannomas (VS). METHODS: Two major computerized legal databases (LexisNexis and WestLaw) were queried and reviewed for evaluation of all the US state and federal court records from civil trials alleging malpractice between 1976 and 2016. RESULTS: A total of 32 VS cases were identified. Allegations were divided into four categories: misdiagnosis/delayed diagnosis (47%), postoperative complications (44%), failure of informed consent or information sharing (16%), and other (3%). Postoperative complications included facial nerve paralysis, myocardial infarction, meningitis, and intracranial hemorrhage. Judgment amounts ranged from $300,000 to $2,000,000. The specialist type was specified for 24 of the 32 cases (75%): neurosurgeons (n = 9; 37%), neurotologists (n = 6; 25%), general otolaryngologists (n = 5; 21%), primary care physicians (n = 4; 17%), neurologists (n = 3; 12%), radiologists (n = 3; 12%), anesthesiologists (n = 2; 8%), radiation oncologists (n = 1; 4%), and general surgeon (n = 1; 4%). Of these 24 cases, (n = 9; 37%) two or more physicians were named as defendants in the lawsuit. CONCLUSIONS: Enhanced physician-patient communication, ensuring proper and adequate patient consent procedures, and proper documentation are good practices that may decrease the likelihood of lawsuits.

Abstract Introduction Neural dysfunction is associated with aberrant nerve firing; thus, electrodiagnosis has the potential for objective diagnosis and quantification of neural dysfunction. Electrical stimulation alters nerve firing and may also have treatment potential. This article outlines some findings related to electrodiagnosis and electrical stimulation of the ear. The quasi‐synchronous firing of many vestibuloacoustic nerve fibers can produce an extracellular potential defined as a field potential (FP). Electrovestibulography (EVestG) is a method to record vestibuloacoustic signals and detect the associated FPs. A clear picture of the muscle‐, EEG‐, saccade‐related, or other artefactual origins, and the physiologic basis of FPs recorded with EVestG, is evolving. EVestG was applied to demonstrate the effect of electrical stimulation on spontaneous FPs in the ear canal. Methods Bilateral EVestG recordings were conducted on 14 guinea pigs before and after stimulation with 3–0.5 mA ipsilateral anodal electrical pulses before and after ablation via unilateral Scarpa's ganglionectomy to elucidate the origin of the EVestG recorded spontaneous FPs. Results Anodal electrical stimulation suppresses the recorded activity. There was a significant reduction of the level of recorded signal observed following anodal stimulation on the ablated but not the intact side. Conclusion Electrical stimulation of the external auditory canal reduces spontaneous electrical activity in the ear canal, some of which is due to central nervous system activity. The EVestG recorded FPs have a major vestibuloacoustic component.

We describe ongoing efforts to better understand the interaction of spoken languages and their physical environments. We begin by briefly surveying research suggesting that languages evolve in ways that are influenced by the physical characteristics of their environments, however the primary focus is on the converse issue: how speech affects the physical environment. We discuss the speech-based production of airflow and aerosol particles that are buoyant in ambient air, based on some of the results in the literature. Most critically, we demonstrate a novel method used to capture aerosol, airflow, and acoustic data simultaneously. This method captures airflow data via a pneumotachograph and aerosol data via an electrical particle impactor. The data are collected underneath a laminar flow hood while participants breathe pure air, thereby eliminating background aerosol particles and isolating those produced during speech. Given the capabilities of the electrical particle impactor, which has not previously been used to analyze speech-based aerosols, the method allows for the detection of aerosol particles at temporal and physical resolutions exceeding those evident in the literature, even enabling the isolation of the role of individual sound types in the production of aerosols. The aerosols detected via this method range in size from 70 nanometers to 10 micrometers in diameter. Such aerosol particles are capable of hosting airborne pathogens. We discuss how this approach could ultimately yield data that are relevant to airborne disease transmission and offer preliminary results that illustrate such relevance. The method described can help uncover the actual articulatory gestures that generate aerosol emissions, as exemplified here through a discussion focused on plosive aspiration and vocal cord vibration. The results we describe illustrate in new ways the unseen and unheard ways in which spoken languages interact with their physical environments.

The designing of acoustic material with high efficiency absorption is cutting edge research for acoustician as well as architectures’ in the acoustic industries attracts the material scientist due to its numerous significant characteristic properties. Nondestructive technique such as ultrasonic processing is employed for surface modification of corn husk which changes the interfacial as well as skeletal arrangement in interlocking of fibers with polymer chain. Tensile strength of single corn husk fiber before and after surface treatment was observed to be increasing from 332.57 MPa to 345.16 MPa, which confirms the strong fibrillation due to surface treatment. Further the hardness of the fabricated corn husk composite was found to be 23HV as observed in three different places. Thermal conductivity of the samples increases with temperature supporting the validation of the sample for acoustic application. The high sound absorption performance of the composite classified the material as Class-A type with 0.94 absorption coefficient supported by the different characterization and surface analysis of the composite.

The vibrational modes of semiconductor and metal nanostructures occur in the MHz to GHz frequency range, depending on dimensions. These modes are at the heart of nano-optomechanical devices, and understanding how they dissipate energy is important for applications of the devices. In this paper ultrafast transient absorption microscopy has been used to examine the breathing modes of a single gold nanoplate, where up to four overtones were observed. Analysis of the frequencies and amplitudes of the modes using a simple continuum mechanics model shows that the system behaves as a free plate, even though it is deposited onto a surface with no special preparation. The overtones decay faster than the fundamental mode, which is not predicted by continuum mechanics calculations of mode damping due to radiation of sound waves. Possible reasons for this effect include frequency dependent thermoelastic effects in the nanoplate, and/or flow of acoustic energy out of the excitation region.

A nonconventional material with remarkable thermal and acoustic insulation properties from aerogels category was experimentally made. Produced from a recycled commercial waste (polyethylene terephthalate-PET) and an industrial by-product (fly ash) as well as a biomaterial (psyllium husk) used for the first time as a binder by mixing with water, the aerogel was subjected to a freeze-drying process. The determination of the product characteristics highlighted extremely low densities (0.022-0.041 g· cm-3), very low thermal conductivities (0.035-0.037 W·m-1·K-1), very high porosities (97.8-98.5 %), mechanical properties superior to those of an unreinforced gel (compression strength of 9.5-16.4 kPa and Young's modulus of 4.15-18.93 kPa), and excellent noise absorption properties (noise reduction coefficient of 0.30-0.33). The manufacturing process of this inexpensive product allows for a clean environment.

Quality detection has been a major problem in the agriculture and food industries. This operation is mostly done by a subjective sensory method which is prone to high error and food destruction. Therefore, there is a need to apply artificial intelligence using a machine learning approach. This study developed two intelligent acoustic yam quality detection and classification devices using two sound-generating techniques. The software (multi-wave frequency generator) sound-generating technique generated sound from a laptop to a speaker inside a detecting chamber. This sound passes through the yam and was received on the opposite side by a microphone, into another laptop for analysis using visual analyzer software. The impact sound-generating technique used sound generated from a gentle impact of the yam on a flat surface placed inside the detection chamber. The sound produced was picked up by a microphone into a laptop for analysis. Acoustic properties considered were amplitude, frequency, sound velocity, wavelength, period and sound intensity. Discriminant analysis algorithm only was used in this first stage of the study to prove the applicability of machine learning. Three qualities (good, diseased damaged and insect-damaged) of two yam varieties (white and yellow yam) were tested. The device's performance of white yam was 79% and 68.7%, yellow yam was 82.3% and 68.7% for the software sound generation-technique and surface impact sound-generating technique, respectively. The study shows that the software sound-generating technique performed better in terms of overall yam quality detection and also proves the applicability of machine learning.

In recent years, piezoelectric nanogenerators have become more attractive than triboelectric nanogenerators due to their more excellent durability in high dust or humidity. Therefore, increasing their output is the subject of many studies. Here the focus is on electrodes of acoustic micro/nanofiber nanogenerators for the first time. Compared to other works here, introducing a new electrode is the aim, and it should be cheap and does not result in lower outputs. Here, for the first time, graphene spin-coated ink was used for a polyacrylonitrile-based acoustic nanogenerator, which gave the output of 60 mV. The results of the acoustic tests were compared with the in situ synthesis of nickel nanoparticles on the layer using graphene spin-coated screen ink and conductive tape, which had the highest outputs of 0, 60 and 120 mV. Additionally, the best way for increasing the output of piezoelectric acoustic nanogenerators is to make composites. Up to now the highest piezoelectric effect is for PAN and its composites have not been investigated yet. Here, as a first step of doing work in this field, I used a copolymer of PAN, because PAN is not a good polymer for doping and it needs functional groups.

Conventional energy sources are continuously depleting, and the world is actively seeking new green and efficient energy solutions. Enormous amounts of acoustic energy are dissipated daily, but the low intensity and limited efficiency of current harvesting techniques are preventing its adoption as a ubiquitous method of power generation. Herein, a strategic solution to increase acoustic energy harvesting efficiency using a specially designed metamaterial is implemented. A scalable transmissive labyrinthine acoustic metamaterial (LAM) is designed, developed, and employed to maximize ultrasound (40 kHz) capture over its large surface area (>27 k mm2), which is focused onto a piezoelectric film (78.6 mm2), thus magnifying incident sound pressure by 13.6 times. Three different piezoelectric films – two commercial and one lab‐made nanocomposite film are tested with LAM in the acoustic energy harvesting system. An extraordinary voltage gain of 157–173% and a maximum power gain of 272% using the LAM compared to the case without the LAM are achieved. Multipoint focusing using holographic techniques, showcasing acoustic patterning to allow on‐demand simultaneous harvesting in separate locations, is demonstrated. Our versatile approach for high‐intensity acoustic energy harvesting opens future opportunities to exploit sound energy as a resource to contribute toward global sustainability. [ABSTRACT FROM AUTHOR]

To obtain accurate soil parameters and improve the accuracy of the acoustic-soil discrete element simulation model, we studied the model's parameter calibration. The simulation test was carried out using the measured acoustic velocity and dominant frequency as the response value (index). Firstly, the Plackett—Burman test scheme was used to obtain the sensitivity ranking of soil parameters to the dominant frequency and velocity of the acoustic wave. The parameters that significantly affect the acoustic wave were obtained: Shear modulus, Poisson's ratio, and coefficient of restitution. Then the Box—Behnken test scheme was used to establish the regression relationship between the dominant frequency and the velocity of the sound wave and Shear modulus, Poisson's ratio, and Coefficient of restitution. The results shows that the indexes that researchers focus on are different in different scenarios, and the sensitivity of soil parameters to different indicators is different, which results in different soil parameter values after calibration. This study analyzed the main factors affecting the accuracy of the acoustic-discrete element model in constructing the model, provided a method for improving the construction accuracy of the acoustic wave—soil discrete element model and provided a reference for the construction of discrete elements models in other fields. [ABSTRACT FROM AUTHOR]

Although positive photobiomodulation response on wound healing, tissue repair, and therapeutic treatment has been widely reported, additional works are still needed to understand its effects on human blood. This research carried out acoustic measurements using A-scan (GAMPT) ultrasonic techniques to elucidate the photobiomodulation effects on in vitro human blood samples as therapeutic treatment measures. The human blood samples were irradiated using a 532-nm laser with different output laser powers (60 and 80 mW) at various exposure times. The ultrasonic velocity measured in the human blood samples after laser irradiation showed significant changes, most of which were within the acceptance limit for soft tissues (1570 ± 30 m/s). Abnormal cells (echinocyte and crenation) were observed due to excessive exposure during laser treatment. [ABSTRACT FROM AUTHOR]

Previous research has found that human voice can provide reliable information to be used for gender identification with a high level of accuracy. In social psychology, perceived masculinity and femininity (masculinity and femininity rated by humans) has often been considered an important feature when investigating the influence of vocal features on social behaviours. While previous studies have characterized the acoustic features that contributed to perceivers' judgements of speakers' masculinity or femininity, there is limited research on developing a machine masculinity/femininity scoring model and characterizing the independent acoustic factors that contribute to perceivers' masculinity and femininity judgements. In this work, we first propose a machine scoring model of perceived masculinity/femininity based on the Extreme Random Forest and then characterize the independent and meaningful acoustic factors that contribute to perceivers' judgements by using a correlation matrix based hierarchical clustering method. Our results show that the machine ratings of masculinity and femininity strongly correlated with the human ratings of masculinity and femininity when we used an optimal speech duration of 7 s, with a correlation coefficient of up to.63 for females and.77 for males. Nine independent clusters of acoustic measures were generated from our modelling of femininity judgements for female voices and eight clusters were found for masculinity judgements for male voices. The results revealed that, for both genders, the F0 mean is the most important acoustic measure affecting the judgement of acoustic-related masculinity and femininity. The F3 mean, F4 mean and VTL estimators were found to be highly inter-correlated and appeared in the same cluster, forming the second most significant factor in influencing the assessment of acoustic-related masculinity and femininity. Next, F1 mean, F2 mean and F0 standard deviation are independent factors that share similar importance. The voice perturbation measures, including HNR, jitter and shimmer, are of lesser importance in influencing masculinity/femininity judgements. • We modelled femininity/masculinity ratings for 129 female/96 male voices. • Extreme Random Forest regression and correlated feature clustering were used. • F0 mean accounted for 23.80% of variance for femininity and 43.5% for masculinity. • A F3 mean/F4 mean/VTL estimators was also a prominent predictor. • Differences in feature weights for femininity and masculinity ratings are discussed. [ABSTRACT FROM AUTHOR]

This paper explores the implementation of an ejector to a micro turbojet engine and analysis of the advantages in terms of acoustic and thrust/fuel consumption. Starting with the analytical equations and a series of numerical simulations, the optimal ejector geometry for maximum thrust was obtained. The ejector was manufactured and integrated with the Jet Cat P80 micro turbo engine for testing. The purpose of this article is to report on an improved geometry that results in no significant increase in the frontal area of the turbo engine, which could increase drag. The tests were completed using various functioning regimes, namely idle, cruise and maximum. For each of them, a comparative analysis between engine parameters with and without an ejector was performed. During the experiments, it was observed that, when the ejector was used, the thrust increased for each regime, and the specific consumption decreased for all regimes. The stability of the engine was tested in transient regimes by performing a sudden acceleration sequence, and one carried out the operating line and the modification of temperature values in front of the turbine for both configurations. For each regime, the acoustic noise was monitored at a few points that were different distances from the nozzle, and a decrease was identified when the ejector was used. The advantages of using the ejector on the Jet Cat P80 turbo jet engine are an increased thrust, a lower specific consumption and a reduced noise level, and at the same time, the integrity of the engine in stable operational states and transient operating regimes is not affected. [ABSTRACT FROM AUTHOR]

As attention to indoor environmental quality (IEQ) grows, a systematic strategy for assessing IEQ in schools needs to be developed. For this purpose, this paper presents a summary of parameters measured in school classrooms to characterize the quality of thermal, acoustic, and visual environments and indoor air quality (IAQ). The summary is based on a review of published literature reporting measurements in schools in Europe and North America in the past ten years. It also summarizes the measurement protocols and measured concentrations. Eighty-eight papers describing measurements in schools were identified and analyzed. No unique standardized measuring method was used in the reviewed studies and different parameters were measured. The most often measured parameters were those describing the thermal environment and IAQ. The former mainly comprised air temperature and relative humidity. The latter mainly comprised concentrations of carbon dioxide, particulate matter, radon, formaldehyde, and some volatile organic compounds. The measured parameters describing acoustic and visual environments mainly comprised noise level, reverberation time, and illuminance. A few studies reported additional measurements of radiant temperature, operative temperature, and speech intelligibility. Measurement protocols from different studies show inconsistency in sampling duration and location and expressed results. Measured concentrations also show high variation between studies, with some pollutants exceeding the threshold values proposed by local and/or international organizations such as the World Health Organization (WHO). This review provides the reference for developing a rating scheme and protocols for uniform characterization of classroom IEQ. [ABSTRACT FROM AUTHOR]

The designing of acoustic material with high efficiency absorption is cutting edge research for acoustician as well as architectures’ in the acoustic industries attracts the material scientist due to its numerous significant characteristic properties. Nondestructive technique such as ultrasonic processing is employed for surface modification of corn husk which changes the interfacial as well as skeletal arrangement in interlocking of fibers with polymer chain. Tensile strength of single corn husk fiber before and after surface treatment was observed to be increasing from 332.57 MPa to 345.16 MPa, which confirms the strong fibrillation due to surface treatment. Further the hardness of the fabricated corn husk composite was found to be 23HV as observed in three different places. Thermal conductivity of the samples increases with temperature supporting the validation of the sample for acoustic application. The high sound absorption performance of the composite classified the material as Class-A type with 0.94 absorption coefficient supported by the different characterization and surface analysis of the composite. [ABSTRACT FROM AUTHOR]

This note compares different approaches to estimating acoustic plane‐wave components from a set of traces recorded by receivers at known locations. The parameters for these plane waves are estimated following somewhat different approaches: 1.A heuristic approach without reference to any optimization schemes).2.A frequency‐domain least‐squares approach: With explicit derivation of separate real and imaginary parts of the complex‐valued wave‐field parameters.Using complex partial differential operators. All approaches give the same solution. Of the three, the first approach gives a better understanding of the physics – the last approach is far more direct and easier. That the results are identical argues for our use of Wirtinger complex partial differential operators for our least‐squares minimization problem. Using these operators allows the complex numbers z and z∗$z^*$ to be considered independent variables, giving ∂∂z(z∗z)=z∗$\frac{\partial }{\partial z}(z^*z)=z^*$. [ABSTRACT FROM AUTHOR]

Objectives: This report seeks to highlight a pitfall that may be encountered in the management of patients with trigeminal neuralgia with imaging showing both neurovascular conflict as well as tumors. Case presentation: A case of a 53 year old male with simultaneous neurovascular conflict and a vestibular schwannoma with trigeminal neuralgia is presented and the management is discussed with reference to managing this particular subset. Pain was noted to be likely generated by neurovascular conflict and not by the tumor, which is usually not the case. Conclusions: It is suggested that in such cases, microvascular decompression should always be performed in addition to removal of the tumor. [ABSTRACT FROM AUTHOR]