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Liquid–liquid extraction is an essential chemical separation technique where polar solutes are extracted from an aqueous phase into a nonpolar organic solvent by amphiphilic extractant molecules. A fundamental limitation to the efficiency of this important technology is third phase formation, wherein the organic phase splits upon sufficient loading of polar solutes. The nanoscale drivers of phase splitting are challenging to understand in the complex hierarchically structured organic phases. In this study, we demonstrate that the organic phase structure and phase behavior are fundamentally connected in a way than can be understood with critical phenomena theory. For a series of binary mixtures of trialkyl phosphate extractants with linear alkane diluents, we combine small angle x-ray scattering and molecular dynamics simulations to demonstrate how the organic phase mesostructure over a wide range of compositions is dominated by critical concentration fluctuations associated with the critical point of the third phase formation phase transition. These findings reconcile many longstanding inconsistencies in the literature where small angle scattering features, also consistent with such critical fluctuations, were interpreted as reverse micellar-like particles. Overall, this study shows how the organic phase mesostructure and phase behavior are intrinsically linked, deepening our understanding of both and providing a new framework for using molecular structure and thermodynamic variables to control mesostructure and phase behavior in liquid–liquid extraction. [ABSTRACT FROM AUTHOR]

Abstract\nIMPLICATIONS FOR REHABILITATIONObjectives: The ability to localize sound sources is crucial for everyday listening, as it contributes to spatial awareness and the detection of warning signs. Individuals with hearing impairment have poorer localization abilities, which further deteriorate when they are fitted with a hearing aid. Although numerous studies have addressed this phenomenon, there is a lack of systematic evidence. The aim of the current systematic review is to address the following research question, “Do behavioural measures of spatial hearing ability improve with bilateral hearing aid fitting compared to the unaided hearing condition?”Design: A comprehensive search was conducted by two independent authors utilizing electronic databases, using various electronic databases, covering the period of 1965 to 2022. The inclusion and exclusion criteria were formulated using the Population, Intervention, Compression, Outcome, and Study design (PICOS) format, and the certainty of evidence was determined using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) guidelines.Results: The comprehensive search resulted in 2199 studies, 17 studies for qualitative synthesis and 15 studies for quantitative synthesis. The collected data was divided into two groups, namely vertical and horizontal localization. The results of the quantitative analysis indicate that the localization performance was significantly better in the unaided condition for both vertical and horizontal planes. The certainty of our evidence was judged to be moderate, meaning that “we are moderately confident in the effect estimate. The true effect is likely to be close to the estimate of the effect, but there is a possibility that it is substantially different”.Conclusion: The review findings demonstrate that the bilateral fitting of the hearing aid did not effectively preserve spatial cues, which resulted in poorer localization performance irrespective of the plane of assessment.Review Registration: Prospective Register of Systematic Reviews (PROSPERO); CRD42022358164Hearing aids are a widely used rehabilitative method to compensate for the loss of audibility in individuals with hearing impairment. The current review highlights that, even though hearing aids can enhance audibility, they often fail to preserve spatial cues.This review paper provides a comprehensive summary of the existing literature, focusing on the preservation of spatial cues by hearing aids and the technologies that can enhance localization performance to a certain degree.The findings of the current study encourage both researchers and hearing aid manufacturers to advance their research methods pertaining to the preservation of spatial cues. This advancement has the potential to improve spatial awareness and possibly improve speech perception in the presence of noise in hearing aid users.Hearing aids are a widely used rehabilitative method to compensate for the loss of audibility in individuals with hearing impairment. The current review highlights that, even though hearing aids can enhance audibility, they often fail to preserve spatial cues.This review paper provides a comprehensive summary of the existing literature, focusing on the preservation of spatial cues by hearing aids and the technologies that can enhance localization performance to a certain degree.The findings of the current study encourage both researchers and hearing aid manufacturers to advance their research methods pertaining to the preservation of spatial cues. This advancement has the potential to improve spatial awareness and possibly improve speech perception in the presence of noise in hearing aid users. [ABSTRACT FROM AUTHOR]

The purpose of this study was to systematically review the available literature on the prevalence, self-reported voice symptoms, and associated risk factors for the development of voice problems in call center operators (CCO). a systematic review An electronic search from five databases based on the guidance of preferred reporting of items for systematic reviews and meta-analysis (PRISMA) yielded 15 articles that reported the different aspects of voice problems in CCOs. The methodological quality of the studies was analyzed using the National Institute of Health (NIH) questionnaire. The career prevalence of voice problems in CCOs varied from 33% to 68%, whereas point prevalence was at 27%. Hoarse/rough voice was the most prominent symptom reported by most of the studies. Vocal fatigue, effortful voice, and breaks/cracks in voice were the other reported vocal symptoms. Long working hours, short breaks between calls, noisy working environment, dry work environment, work stress, stressful calls, limited breaks, prolonged use of voice, insufficient vocal rest, throat clearing, and more caffeinated beverage intake were different risk factors having significant association with telemarketers reporting vocal symptoms. The present study results suggest that CCOs are at higher risk of developing voice problems. Further, the different vocal symptoms reported by CCOs are suggestive of vocal fatigue. In addition, multiple risk factors may be associated with the development of voice problems. However, the available literature is limited, and further studies with a larger sample size are required to corroborate the current findings. [ABSTRACT FROM AUTHOR]

We report on pH- and salt-responsive assembly of nanoparticles capped with polyelectrolytes at vapor-liquid interfaces. Two types of alkylthiol-terminated poly(acrylic acid) (PAAs, varying in length) are synthesized and used to functionalize gold nanoparticles (AuNPs) to mimic similar assembly effects of single-stranded DNA-capped AuNPs using synthetic polyelectrolytes. Using surface-sensitive X-ray scattering techniques, including grazing incidence small-angle X-ray scattering (GISAXS) and X-ray reflectivity (XRR), we demonstrate that PAA-AuNPs spontaneously migrate to the vapor-liquid interfaces and form Gibbs monolayers by decreasing the pH of the suspension. The Gibbs monoalyers show chainlike structures of monoparticle thickness. The pH-induced self-assembly is attributed to the protonation of carboxyl groups and to hydrogen bonding between the neighboring PAA-AuNPs. In addition, we show that adding MgCl2 to PAA-AuNP suspensions also induces adsorption at the interface and that the high affinity between magnesium ions and carboxyl groups leads to two- and three-dimensional clusters that yield partial surface coverage and poorer ordering of NPs at the interface. We also examine the assembly of PAA-AuNPs in the presence of a positively charged Langmuir monolayer that promotes the attraction of the negatively charged capped NPs by electrostatic forces. Our results show that synthetic polyelectrolyte-functionalized nanoparticles exhibit interfacial self-assembly behavior similar to that of DNA-functionalized nanoparticles, providing a pathway for nanoparticle assembly in general. [ABSTRACT FROM AUTHOR]