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Ascertaining the presence of weakly positive anti-HLA donor-specific antibodies (DSA) in organ transplantation with multiplex single antigen beads assays may be challenging despite their high sensitivity due to technical variability issues. Through extensive datasets of Next-Generation Sequencing HLA typings and single antigen analyses, we reassessed the mean fluorescence intensity (MFI) positivity threshold of the assay to enhance accuracy. By showing that some beads were more prone to false positivity than others, we propose a nuanced approach that accounts for nonspecific intrinsic reactivities at the HLA antigen level, that is, on a bead-by-bead basis, as it enhances assay precision and reliability. This is substantiated by a comprehensive statistical analysis of MFI values and the implementation of the determination of a "Quantile Adjusted Threshold 500" (QAT500) value for each bead. Applied to DSA detection during patients' follow-up, this approach discriminated better and earlier low-strength DSA that would later raise their MFI above the clinically relevant threshold of 3000. Moving from a subjective interpretation to a more objective and precise methodology allows for standardizing HLA antibody and DSA detection. The study emphasizes the need for further research with real clinical data to validate and refine this approach.

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Aiming at the problem that the existing methods are insufficient in dealing with the background noise anti-interference of underwater fish images, a contrastive learning method of ignoring background called CLIB for underwater fish image classification is proposed to improve the accuracy and robustness of underwater fish image classification. First, CLIB effectively separates the subject from the background in the image through the extraction module and applies it to contrastive learning by composing three complementary views with the original image. To further improve the adaptive ability of CLIB in complex underwater images, we propose a multi-view-based contrastive loss function, whose core idea is to enhance the similarity between the original image and the subject and maximize the difference between the subject and the background, making CLIB focus more on learning the core features of the subject during the training process, and effectively ignoring the interference of background noise. Experiments on the Fish4Knowledge, Fish-gres, WildFish-30, and QUTFish-89 public datasets show that our method performs well, with improvements of 1.43-6.75%, 8.16-8.95%, 13.1-14.82%, and 3.92-6.19%, respectively, compared with the baseline model, further validating the effectiveness of CLIB.

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OBJECTIVE: People with hearing loss often encounter difficulties in hearing under adverse conditions, such as listening in the presence of noise. Listening effort is an indicator used to assess listening difficulties in daily life. Although many studies on listening effort have been conducted in recent years, there is a notable gap in the exploration of how task load influences listening effort in young adults. This study compared the effects of background noise and memory load on task performance and subjective listening effort in young adults with and without hearing loss. METHODS: The study included a group of 8 adults with hearing loss (mean age: 24.1 ± 6.0 years) and a group of 16 individuals with normal hearing (mean age: 27.9 ± 4.9 years). A number memorizing task was conducted, involving two types of auditory digits (either three or seven digits) presented under multi-talker babble noise conditions of signal-to-noise ratio of -5 dB [SN -5 dB] or SN +5 dB. Participants determined whether the number presented in the encoding interval matched the one presented in the retrieval interval. Subsequently, they were asked to complete a questionnaire using a Visual Analog Scale (VAS) to assess their subjective listening effort. Percentage of correct responses, reaction times, and VAS ratings were compared between adults with and without hearing loss. RESULTS: Our results showed significant differences between the two groups in the percentage of correct responses and the reaction time under the SN -5 dB conditions, regardless of the memory load. Under the SN +5 dB conditions, a significant difference was found only in the percentage of correct responses for seven digits. In the normal hearing group, the percentage of correct responses and VAS ratings tended to decrease as the memory load increased, even under the same noise condition. Conversely, in the hearing loss group, a consistent trend could not be identified in the effects of noise and memory load on the percentage of correct responses and VAS ratings. CONCLUSION: These results suggest that in conditions of high noise load, young adults with hearing loss show a higher tendency for listening effort to be affected by other loads. We confirmed that for some participants with hearing loss, the task exceeded a certain level of difficulty in the SN -5 dB and seven digits condition, leading to a change in their motivation and strategy used. Future research should examine ways to control for participants' motivations.

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INTRODUCTION: Older adults experiencing normal aging make up most patients seeking services at audiology clinics. While research acknowledges that the speech perception abilities of aging adults can be diminished in lower-level speech identification or discrimination, there is less concern about how aging affects higher-level speech understanding, particularly in tonal languages. This study aimed to explore the effects of aging on the comprehension of implied intentions conveyed through prosodic features in Mandarin focus sentences, both in quiet and noisy environments. METHODS: Twenty-seven younger listeners (aged 17 to 26) and 27 older listeners (aged 58 to 77) participated in a focus comprehension task. Their task was to interpret SAVO (subject-adverbial-verb-object) sentences with five focus conditions (initial subject-focus, medial adverbial-focus, medial verb-focus, final object-focus, and neutral non-focus) across five background conditions: quiet, white noise (at 0 and -10-dB signal-to-noise ratios, SNRs), and competing speech (at 0 and -10-dB SNRs). Comprehension performances were analyzed based on accuracy rates, and underlying processing patterns were evaluated using confusion matrices. RESULTS: Younger listeners consistently excelled across focus conditions in quiet settings, but their scores declined in white noise at the SNR of -10-dB. Older adults exhibited variability in scores across focus conditions but not in background conditions. They scored lower than their younger counterparts, with the highest scores observed in the comprehension of sentences featuring a medial adverbial-focus. Analysis of confusion matrices revealed that younger adults seldom mistook focus conditions, whereas older adults tended to comprehend the other focused items as medial adverbials. CONCLUSIONS: Older listeners' performance reflects their over-reliance on top-down language knowledge, while their bottom-up acoustic processing decreases when interpreting Mandarin focus sentences. These findings provide evidence of active cognitive processing in prosody comprehension among aging adults and offer insights for diagnosing and intervening with speech disorders in clinical settings.

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Microhaplotypes (MHs), comprising two or more single-nucleotide polymorphisms in a short fragment, are promising forensic markers owing to their remarkable polymorphic nature. Several studies have demonstrated the utility of MHs through massively parallel sequencing (MPS). Nevertheless, the background noise level associated with MHs in MPS, which imposes a practical detection limit for the system, remains uninvestigated. Currently, unique molecular identifier (UMI) systems are known to effectively mitigate background noise by tracking original DNA molecules and facilitating PCR and MPS error corrections. Hence, this study aimed to design a UMI-based amplicon sequencing system, designated MH-UMIseq, which can amplify 46 MHs simultaneously and generate MPS libraries in four steps: barcoding PCR, nuclease reaction, boosting PCR, and indexing PCR. The performance of the MH-UMIseq system was evaluated using the Illumina NextSeq 550 and MiniSeq systems with 31 sets for 5 ng, 1 ng, and 200 pg of input DNA. The fgbio toolkit was used in conjunction with STRait Razor 3.0 and Visual Microhap to analyze the UMI data on MHs. The corresponding average not suppressed noise proportion of MH-UMIseq were 0.1 %, 0.3 %, and 0.7 % for 5 ng, 1 ng, and 200 pg of DNA, respectively, which substantially suppressed the background noise for more than 1 ng of DNA. Interestingly, the proportion of not suppressed noise in MH-UMIseq notably decreased as the amount of input DNA increased. The number of UMI families was proportional to the copy number of the template DNA and closely correlated with the system resolution. Therefore, the resolution of MH-UMIseq system is expected to be higher than that of conventional MPS for the deconvolution of mixtures containing more than 1 ng of DNA.

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Listeners exhibit varying levels of tolerance for background noise during speech communication. It has been proposed that low tolerance of background noise may be the consequence of abnormally amplified gain in the central auditory system (CAS). Here, using a dataset of young adults with normal hearing thresholds, we asked whether central gain mechanisms might also explain cases of hypertolerance of background noise, as well as cases of reduced, but not abnormal, tolerance. We used the auditory brainstem response to derive a measure of CAS gain (wave V/wave I ratio) to compare listeners' background noise tolerance while listening to speech, grouping them into three categories: hyper, high, and medium tolerance. We found that hypertolerant listeners had reduced CAS gain compared to those with high tolerance. This effect was driven by wave V not wave I. In addition, the medium tolerant listeners trended toward having reduced wave I and reduced wave V amplitudes and generally higher levels of exposure to loud sound, suggestive of the early stages of noise-compromised peripheral function without an apparent compensatory increase in central gain. Our results provide physiological evidence that 1) reduced CAS gain may account for hypertolerance of background noise but that 2) increased CAS gain is not a prerequisite for medium tolerance of background noise.NEW & NOTEWORTHY Our findings strengthen the proposed mechanistic connection between background noise tolerance and auditory physiology by suggesting a link between hypertolerance and reduced central auditory gain, measured by the auditory brainstem response.

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Photoacoustic imaging (PAI) can sensitively detect regions and substances with strong optical absorption, which means that diseased tissue can be imaged with high contrast in the presence of surrounding healthy tissue through the photoacoustic effect. However, its signal intensity and resolution may be limited by background signals generated by endogenous chromophores such as melanin and hemoglobin. A feasible method for practical application of this so-called background-suppressed PAI is still lacking. In this work, a dual-wavelength differential background noise-suppressed photoacoustic tomography is developed based on organic semiconducting polymer dots (Pdots). The Pdots have a strong absorption peak at 945 nm, and then the absorption decreases sharply with the increase of wavelength, and the absorption intensity drops to only about a quarter of the original value at 1050 nm. The present system significantly suppresses the strong background noise of blood through dual-wavelength differential PAI, enabling precise monitoring of the distribution information of theranostic agents in diseased tissues. The signal-to-noise ratio of the theranostic agent distribution map is increased by about 20 dB. This work provides a platform for real-time and accurate monitoring of tumors and drugs, which helps avoid damage to healthy tissue during treatment and has clinical significance in cancer treatment.

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Auditory distractions can impair the sensory evaluation of food; however, the specific impact of airplane cabin noise on the sensory perception of in-flight meals remains poorly studied. Here, we investigated the effects of airplane cabin noise on the visual processing of in-flight meal stimuli using electroencephalography (EEG) in twenty healthy male subjects. Resting-state EEG and event-related potential (ERP) responses to in-flight meal images were acquired during quiet and simulated cabin noise conditions. Participants reported mild discomfort and some loss of appetite when exposed to airplane cabin noise. The analysis of resting-state EEG showed an increase in the absolute power of theta and beta frequency bands in the left superior parietal and left frontal/right central regions under simulated cabin noise conditions, compared to quiet conditions. The ERP results showed that the amplitude of responses evoked by visual meal images in the superior parietal area was reduced in the noise condition compared to the quiet condition. Our findings suggest that airplane cabin noise disrupts the visual perception and attentional processing of in-flight food stimuli. These neural changes imply an impact on integrating sensory information, resulting in altered sensory evaluations of food during in-flight dining experiences.

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Underwater noise pollution has become a potential threat to aquatic animals in the natural environment. The main causes of such pollution are frequent human activities creating underwater environmental noise, including commercial shipping, offshore energy platforms, scientific exploration activities, etc. However, in aquaculture environments, underwater noise pollution has also become an unavoidable problem due to background noise created by aquaculture equipment. Some research has shown that certain fish show adaptability to noise over a period of time. This could be due to fish's special auditory organ, i.e., their "inner ear"; meanwhile, otoliths and sensory hair cells are the important components of the inner ear and are also essential for the function of the auditory system. Recently, research in respect of underwater noise pollution has mainly focused on adult fish, and there is a lack of the research on the effects of underwater noise pollution on the development process of the auditory system in the embryonic development period. Thus, in this study, we collected embryo-larval samples of the small yellow croaker (Larimichthys polyactis) in four important stages of otic vesicle development through artificial breeding. Then, we used metabonomics and transcriptomics analyses to reveal the development process of the auditory system in the embryonic development period under background noise (indoor and underwater environment sound). Finally, we identified 4026 differentially expressed genes (DEGs) and 672 differential metabolites (DMs), including 37 DEGs associated with the auditory system, and many differences mainly existed in the neurula stage (20 h of post-fertilization/20 HPF). We also inferred the regulatory mode and process of some important DEGs (Dnmt1, CPS1, and endothelin-1) in the early development of the auditory system. In conclusion, we suggest that the auditory system development of L. polyactis begins at least in the neurula stage or earlier; the other three stages (tail bud stage, caudal fin fold stage, and heart pulsation stage, 28-35 HPF) mark the rapid development period. We speculate that the effect of underwater noise pollution on the embryo-larval stage probably begins even earlier.

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Speech-in-noise testing has been proposed as a useful part of the audiometric test battery dating back to the earliest years of the field of audiology. Many speech-in-noise tests have been developed and used to varying degrees. However, multiple barriers have prevented speech-in-noise testing from being used widely in the clinic. The purpose of this article is to provide a resource to audiologists and other hearing health professionals who want to know (1) what tests are available for use, (2) the rationale behind specific tests, and (3) important considerations when selecting one or more tests to use clinically. In addition, data are presented for four speech-in-noise tests with the purpose of comparing outcomes as a function of age and hearing status. The four tests (QuickSIN, Words in Noise [WIN], Listening in Spatialized Noise-Sentences [LiSN-S], and Coordinate Response Measure [CRM]) were completed by 30 individuals from three groups: 10 young adults with normal hearing, 10 older adults with normal hearing, and 10 older adults with hearing loss. The results suggest that, despite significant differences in performance between groups, group overlap was present such that some individuals from one group performed similar to some individuals of other groups; therefore, individual performance was more important than associated group. When selecting an appropriate speech-in-noise test to use clinically, audiologists should carefully consider the purpose of their testing and the type of information they desire as an outcome. A quick-resource table and appendix is provided to aid audiologists and other health professionals in their selection of an appropriate speech-in-noise test.

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Fractional vegetation cover (FVC) is a crucial indicator to estimate degradation and desertification for grasslands. However, traditional small-scale FVC analysis methods, such as visual estimation and point-sampling, are cumbersome and imprecise. Innovative methods like image-based FVC analysis methods, while accurate, face challenges such as complex analytical procedures and the necessary training for operations. Therefore, in this study, a combined application of ImageJ and Photoshop was employed to achieve a more effective analysis of FVC values in desertification areas. Our results showed that the FVC results obtained by combination of Photoshop and ImageJ were dependable and precise (R2 > 0.98), demonstrating equivalency to results obtained through either visual estimation or Photoshop-based methods. Furthermore, even in the face of background interference and varied shooting angles, the combination of ImageJ and Photoshop software was still able to maintain a low error rate when analyzing FVC values (average error rate = - 2.6%). In conclusion, the imaged-based combined FVC analysis method employed in our research was an effective, precise, and efficient technique for analyzing small-scale FVC, promising substantial improvement over conventional methods.

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Research within the language sciences has informed our understanding of how children build vocabulary knowledge especially during early childhood and the early school years. However, to date, our understanding of word learning in children is based primarily on research in quiet laboratory settings. The everyday environments that children inhabit such as schools, homes, and day cares are typically noisy. To better understand vocabulary development, we need to understand the effects of background noise on word learning. To gain this understanding, a cross-disciplinary approach between researchers in the language and hearing sciences in partnership with parents, educators, and clinicians is ideal. Through this approach we can identify characteristics of effective vocabulary instruction that take into account the background noise present in children's learning environments. Furthermore, we can identify characteristics of children who are likely to struggle with learning words in noisy environments. For example, differences in vocabulary knowledge, verbal working memory abilities, and attention skills will likely influence children's ability to learn words in the presence of background noise. These children require effective interventions to support their vocabulary development which subsequently should support their ability to process and learn language in noisy environments. Overall, this cross-disciplinary approach will inform theories of language development and inform educational and intervention practices designed to support children's vocabulary development. This article is categorized under: Psychology > Language Psychology > Learning Psychology > Theory and Methods.

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Noise-induced tinnitus is generally associated with hearing impairment caused by traumatic acoustic overexposure. Previous studies in laboratory animals and human subjects, however, have observed differences in tinnitus susceptibility, even among individuals with similar hearing loss. The mechanisms underlying increased sensitivity or, conversely, resistance to tinnitus are still incompletely understood. Here, we used behavioral tests and ABR audiometry to compare the sound-evoked responses of mice that differed in the presence of noise-induced tinnitus. The aim was to find a specific pre-exposure neurophysiological marker that would predict the development of tinnitus after acoustic trauma. Noise-exposed mice were screened for tinnitus-like behavior with the GPIAS paradigm and subsequently divided into tinnitus (+T) and non-tinnitus (-T) groups. Both groups showed hearing loss after exposure, manifested by elevated audiometric thresholds along with reduced amplitudes and prolonged latencies of ABR waves. Prior to exposure, except for a slightly increased slope of growth function for ABR amplitudes in +T mice, the two groups did not show significant audiometric differences. Behavioral measures, such as the magnitude of the acoustic startle response and its inhibition by gap pre-pulse, were also similar before exposure in both groups. However, +T mice showed significantly increased suppression of the acoustic startle response in the presence of background noise of moderate intensity. Thus, increased modulation of startle by background sounds may represent a behavioral correlate of susceptibility to noise-induced tinnitus, and its measurement may form the basis of a simple non-invasive method for predicting tinnitus development in laboratory rodents.

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Objectives: This was a single-subject study, aimed to demonstrate different vocal demand situations that are typical for primary school and teacher's vocal demand response under two acoustical conditions, with and without voice amplification, during five working days. Methods: The long-term voice dosimetry with Vocal Holter Med (PR.O. Voice Srl) was carried out on a 49-year-old female teacher with voice disorders during daily teaching activities. A sound field amplification system (SFAS) PentaClass Runa was installed in the classroom. Voice dosimetry was provided under two different acoustical conditions: without SFAS (2 days) and with SFAS (3 days). Results: Phonation time percentage, sound pressure level (SPL), SPL SD, fundamental frequency (F0), F0 SD, cycle, and distance doses were investigated in seven communication scenarios (lessons, group/individual classes, sports lessons in the gym and schoolyard, breaks, lunch breaks, and other activities). The median scores of all voice parameters differed significantly between different vocal demand contexts. The significant statistical difference in the vocal demand response was in the communication situations with and without SFAS. In addition, the number of children, reverberation time, and ambient air relative humidity impacted voice SPL and the cycle dose. Conclusions: Lessons, sports lessons held in the gym or schoolyard, breaks, and lunch breaks were considered as high vocal demand communication situations requiring higher voice intensity and fundamental frequency, higher phonation time percentage, cycle, and distance doses. Group/individual work and other teacher activities during the day, unrelated to direct work with students, were categorized as low vocal demand communication scenarios.

Objetivos: Este fue un estudio de sujeto único, cuyo objetivo fue demostrar diferentes situaciones de demanda vocal típicas de la escuela primaria y la respuesta vocal de los docentes bajo dos condiciones acústicas, con y sin amplificación de voz, durante cinco días laborables. Métodos: Se llevó a cabo dosimetría vocal a largo plazo con Vocal Holter Med (PR.O. Voice Srl) durante las actividades diarias de enseñanza en una docente de 49 años con trastornos de la voz. Se instaló un sistema de amplificación de campo sonoro (SFAS) PentaClass Runa en el aula. La dosimetría vocal se realizó bajo dos condiciones acústicas diferentes: sin SFAS (2 días) y con SFAS (3 días). Resultados: Se investigaron el porcentaje de tiempo de fonación, el nivel de presión sonora (SPL), SPL SD, la frecuencia fundamental (F0), F0 SD, ciclos y dosis de distancia en siete escenarios de comunicación diferentes (clases, clases grupales/individuales, clases de educación física en el gimnasio y el patio de la escuela, recreos, almuerzos y otras actividades). Las puntuaciones medias de todos los parámetros vocales diferían significativamente entre los diferentes contextos de demanda vocal. La diferencia estadísticamente significativa en la respuesta a la demanda vocal se observó en las situaciones de comunicación con y sin SFAS. Además, el número de niños, el tiempo de reverberación y la humedad relativa del aire ambiente afectaron al SPL de la voz y la dosis de ciclo. Conclusiones: Las lecciones, las clases de educación física en el gimnasio o el patio de la escuela, los recreos y los almuerzos se consideraron situaciones de comunicación de alta demanda vocal, que requerían una mayor intensidad y frecuencia fundamental de la voz, un mayor porcentaje de tiempo de fonación y dosis de ciclo y distancia más altas. El trabajo grupal/individual y otras actividades del profesor durante el día no relacionadas con el trabajo directo con los estudiantes se categorizaron como escenarios de comunicación de baja demanda vocal.

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Everyday speech communication often occurs in environments with background noise, and the impact of noise on speech recognition can vary depending on factors such as noise type, noise intensity, and the listener's hearing ability. However, the extent to which neural mechanisms in speech understanding are influenced by different types and levels of noise remains unknown. This study aims to investigate whether individuals exhibit distinct neural responses and attention strategies depending on noise conditions. We recorded electroencephalography (EEG) data from 20 participants with normal hearing (13 males) and evaluated both neural tracking of speech envelopes and behavioral performance in speech understanding in the presence of varying types of background noise. Participants engaged in an EEG experiment consisting of two separate sessions. The first session involved listening to a 12-min story presented binaurally without any background noise. In the second session, speech understanding scores were measured using matrix sentences presented under speech-shaped noise (SSN) and Story noise background noise conditions at noise levels corresponding to sentence recognitions score (SRS). We observed differences in neural envelope correlation depending on noise type but not on its level. Interestingly, the impact of noise type on the variation in envelope tracking was more significant among participants with higher speech perception scores, while those with lower scores exhibited similarities in envelope correlation regardless of the noise condition. The findings suggest that even individuals with normal hearing could adopt different strategies to understand speech in challenging listening environments, depending on the type of noise.

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Background: Animal communication consists of signal production and perception, which are crucial for social interactions. The main form used by anurans is auditory communication, in most cases produced as advertisement calls. Furthermore, sound perception happens mainly through an external tympanic membrane, and plays an important role in social behavior. In this study, we evaluated the influence of body and tympanic membrane sizes on call frequency across the phylogeny of anurans. Methods: We use data on snout-vent length, tympanic membrane diameter, and dominant frequency of the advertisement call from the literature and from natural history museum collections. We mapped these traits across the anuran phylogeny and tested different models of diversification. Our final dataset includes data on body size, tympanic membrane size, and call dominant frequency of 735 anuran species. Results: The best explanatory model includes body and tympanum size with no interaction term. Although our results show that call frequency is strongly constrained by body and tympanum size, we identify five evolutionary shifts in allometry from that ancestral constraint. We relate these evolutionary shifts to the background noise experienced by populations. Body size is important for myriad ecological interactions and tympanum size is strongly associated with female call frequency preferences. Thus, allometric escape in frog calls might arise through environmental selection such as breeding in fast flowing or soundscape competition, as well as sexual selection linked to tympanum size.

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Speech perception is challenging under adverse conditions. However, there is limited evidence regarding how multiple adverse conditions affect speech perception. The present study investigated two conditions that are frequently encountered in real-life communication: background noise and breathy vocal quality. The study first examined the effects of background noise and breathiness on speech perception as measured by intelligibility. Secondly, the study tested the hypothesis that both noise and breathiness affect listening effort, as indicated by linear and nonlinear changes in pupil dilation. Low-context sentences were resynthesized to create three levels of breathiness (original, mild-moderate, and severe). The sentences were presented in a fluctuating nonspeech noise with two signal-to-noise ratios (SNRs) of -5 dB (favorable) and -9 dB (adverse) SNR. Speech intelligibility and pupil dilation data were collected from young listeners with normal hearing thresholds. The results demonstrated that a breathy vocal quality presented in noise negatively affected speech intelligibility, with the degree of breathiness playing a critical role. Listening effort, as measured by the magnitude of pupil dilation, showed significant effects with both severe and mild-moderate breathy voices that were independent of noise level. The findings contributed to the literature by demonstrating the impact of vocal quality on the perception of speech in noise. They also highlighted the complex dynamics between overall task demand and processing resources in understanding the combined impact of multiple adverse conditions.

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BACKGROUND: As the world becomes increasingly interconnected, the demand for bilingual teachers has grown exponentially. However, the unique combination of being a bilingual occupational voice user establishes challenges that warrant careful examination. OBJECTIVE: To investigate the association between bilingualism, vocal effort, and background noise with fundamental frequency and long-term spectrum average among Spanish-English bilingual teachers. METHODS: Exploratory cross-sectional correlational study with the participation of eight Spanish-English proficient bilingual teachers (native Spanish speakers) who were teaching online classes during the quarantines established to mitigate the propagation of COVID-19. Participants were asked to read two standardized texts (one in English and one in Spanish) under two background noise conditions (with and without background white noise). RESULTS: There was a significant interaction between language and vocal effort considering that the association of vocal effort with fo was different for Spanish and English. There was also a significant main effect of background noise on fo. There were significant differences in voice spectral characteristics between productions in Spanish and English and between productions with and without background noise. The alpha ratio was significantly higher in productions in English and with background noise compared with productions in Spanish without background noise. The mid to high spectral energy ratio (1-5 K/5-8 K) was significantly lower in productions in English and with higher perceived vocal effort compared with productions in Spanish and with lower scores on the Borg Scale. CONCLUSION: Our findings introduce a need perspective by emphasizing the impact of speaking a second language on the work-relatedness of voice disorders among teachers. These findings stress the necessity to factor in language and environmental conditions for the comprehensive evaluation and management of work-related voice disorders.

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Antecedentes y objetivos: Las investigaciones que involucran el análisis acústico no siempre consideran el nivel de ruido de fondo del recinto donde van a realizar el proceso de grabación o si lo hacen el valor máximo de ruido de fondo que utilizan varía de autor en autor. El objetivo de esta investigación es determinar si los parámetros: f0, Jitter, Shimmer y Alpha ratio varían en relación con los distintos niveles de ruido de fondo del recinto donde se realiza la grabación, y determinar un valor máximo de este. Materiales y métodos Se utilizó el programa Praat® para obtener el valor promedio de los parámetros: f0, Jitter, Shimmer y Alpha ratio a partir de una muestra de voz en 33 sujetos al interior de una cabina Audiométrica cuyo nivel de ruido de fondo fue de 28,1dB(A). Se realizó una comparación estadística entre el valor promedio de cada parámetro al ir incrementando el nivel de ruido de fondo en relación con los valores promedio obtenidos con el nivel de ruido de fondo basal de la cabina para cada parámetro. Resultados Los parámetros f0 y Alpha ratio, muestran valores confiables hasta un nivel de ruido de fondo de 47,7dB(A), mientras que los parámetros Jitter y Shimmer lo hacen hasta un nivel de ruido de fondo de 43,8dB(A). Conclusiones Considerando que los parámetros acústicos se obtienen todos de la misma grabación, podemos señalar que el nivel de ruido de fondo máximo recomendable en el recinto donde se realicen las grabaciones debiese ser no superior a los 43,8dB(A). (AU)

Background and objectives: Research involving acoustic analysis does not always consider the level of background noise in the room where the recording process is going to be carried out, or if they do, the maximum value of background noise used varies from author to author. The objective of this research is to establish if the parameters: f0, Jitter, Shimmer and Alpha ratio vary in relation to different levels of background noise in the room where the recording process is carried out and to establish a maximum value of this. Materials and methods The Praat program was used to get the average value of the parameters: f0, Jitter, Shimmer and Alpha ratio from a voice sample of 33 subjects inside an audiometric booth whose background noise level was 28.1dB(A). A statistical comparison was made between the average value of each parameter as the background noise increased in relation to the average values obtained with the baseline background noise of the cabin for each parameter. Results The f0 and Alpha ratio parameters show reliable values up to a background noise level of 47.7dB(A), while the Jitter and Shimmer parameters do so up to a background noise level of 43.8dB(A). Conclusions Considering that the acoustic parameters are all obtained from the same recording, we can point out that the recommended maximum background noise level in the room where the recordings are made should not exceed 43.8dB(A). (AU)

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Background noise elicits listening effort. What else is tinnitus if not an endogenous background noise? From such reasoning, we hypothesized the occurrence of increased listening effort in tinnitus patients during listening tasks. Such a hypothesis was tested by investigating some indices of listening effort through electroencephalographic and skin conductance, particularly parietal and frontal alpha and electrodermal activity (EDA). Furthermore, tinnitus distress questionnaires (THI and TQ12-I) were employed. Parietal alpha values were positively correlated to TQ12-I scores, and both were negatively correlated to EDA; Pre-stimulus frontal alpha correlated with the THI score in our pilot study; finally, results showed a general trend of increased frontal alpha activity in the tinnitus group in comparison to the control group. Parietal alpha during the listening to stimuli, positively correlated to the TQ12-I, appears to reflect a higher listening effort in tinnitus patients and the perception of tinnitus symptoms. The negative correlation between both listening effort (parietal alpha) and tinnitus symptoms perception (TQ12-I scores) with EDA levels could be explained by a less responsive sympathetic nervous system to prepare the body to expend increased energy during the "fight or flight" response, due to pauperization of energy from tinnitus perception.