Sources and Extraction of Biopolymers and Manufacturing of Bio-Based Nanocomposites for Different Applications.

In the recent era, bio-nanocomposites represent an emerging group of nanostructured hybrid materials and have been included in a new field at the frontier of materials science, life sciences, and nanotechnology. These biohybrid materials reveal developed structural and functional features of great attention for diverse uses. These materials take advantage of the synergistic assembling of biopolymers with nanometer-sized reinforcements. Conversely, polysaccharides have received great attention due to their several biological properties like antimicrobial and antioxidant performance. They mainly originated in different parts of plants, animals, seaweed, and microorganisms (bacteria, fungi, and yeasts). Polysaccharide-based nanocomposites have great features, like developed physical, structural, and functional features; affordability; biodegradability; and biocompatibility. These bio-based nanocomposites have been applied in biomedical, water treatment, food industries, etc. This paper will focus on the very recent trends in bio-nanocomposite based on polysaccharides for diverse applications. Sources and extraction methods of polysaccharides and preparation methods of their nanocomposites will be discussed.

Influence of Linear Diamine Counterions on the Self-Assembly of Glycine-, Alanine-, Valine-, and Leucine-Based Amphiphiles.

Electrical conductimetry and dynamic light scattering (DLS) were used to investigate the aggregation behaviors of four amino acid-based surfactants (AABSs; undecanoyl-glycine, undecanoyl-l-alanine, undecanoyl-l-valine, undecanoyl-l-leucine) in the presence of five linear diamine counterions (1,2-diaminoethane, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane). Electrical conductimetry was used to measure the CMCs for each system, which ranged from 5.1 to 22.5 mM. With respect to counterions, the obtained CMCs decreased with increases in the interamine spacer length; this was attributed to the improved torsional binding flexibility in longer counterions. Strong linear correlations (mean R2 = 0.9443) were observed between the CMCs and predicted surfactant partition coefficients (logP; water/octanol), suggesting that micellization is primarily driven by the AABS's hydrophobicity for these systems. However, significant deviations in this linear relationship were observed for systems containing 1,2-diaminoethane, 1,4-diaminobutane, and 1,6-diaminohexane (p = 0.0774), suggesting altered binding dynamics for these counterions. pH measurements during the CMC determination experiments indicated the full deprotonation of the AABSs but did not give clear insights into the counterion protonation states, thus yielding an inconclusive evaluation of their charge stabilization effects during binding. However, DLS measurements revealed that the micellar size remained largely independent of the counterion length for counterions longer than 1,2-diaminoethane, with hydrodynamic diameters ranging from 2.2 to 2.8 nm. This was explained by the formation of charge-stabilized noncovalent dimers, with each counterion bearing a full +2 charge. Conductimetry-based estimates of the degrees of counterion binding (ß) and free energies of micellization (ΔG°M) revealed that bulky AABSs exhibit preferential binding to counterions with an even number of methylene groups. It is proposed that when these counterions form noncovalent dimers, perturbations in their natural geometries result in the formation of a binding pocket that accommodates the AABS steric bulk. While the direct application of these systems remains to be seen, this study provides valuable insights into the structure-property relationships that govern AABS aggregation.

Recent Progress on Covalent Organic Frameworks Supporting Metal Nanoparticles as Promising Materials for Nitrophenol Reduction.

With the utilization of nitrophenols in manufacturing various materials and the expansion of industry, nitrophenols have emerged as water pollutants that pose significant risks to both humans and the environment. Therefore, it is imperative to convert nitrophenols into aminophenols, which are less toxic. This conversion process is achieved through the use of noble metal nanoparticles, such as gold, silver, copper, and palladium. The primary challenge with noble metal nanoparticles lies in their accumulation and deactivation, leading to a decrease in catalyst activity. Covalent organic frameworks (COFs) are materials characterized by a crystalline structure, good stability, and high porosity with active sites. These properties make them ideal substrates for noble metal nanoparticles, enhancing catalytic activity. This overview explores various articles that focus on the synthesis of catalysts containing noble metal nanoparticles attached to COFs as substrates to reduce nitrophenols to aminophenols.

Reducing Vocal Fatigue While Preserving Realism During Video Game Voice-Overs Using the Vocal Combat Technique: A Randomized Controlled Trial.

OBJECTIVE: Vocal Combat Technique (VCT) teaches indirect and direct behavioral voice techniques to voice-over artists performing in violent video games. Although previous work on VCT has shown promise for mitigating dysphonia symptoms, a randomized clinical trial has yet to be undertaken. Therefore, we completed a randomized, controlled trial between a group of experienced video game voice-over actors receiving VCT and a control group comparison. METHODS: A total of 24 video game voice-over actors completed this study. Participants were randomly assigned to receive VCT or indirect vocal hygiene training prior to completing an intensive 1-hour video game voice recording session. The primary outcome was a change in Voice Handicap Index-10 (VHI-10) preperformance/postperformance. Secondary measures included a modified version of the Evaluation of the Ability to Sing Easily (m-EASE), the Vocal Tract Discomfort Scale (VTDS), and questions regarding return to work. Participants were also rated on the realism of their vocal performance by a blinded video game director. RESULTS: The VCT group showed a significantly smaller change in VHI-10 and m-EASE scores postperformance, and a higher increased likelihood to return to work compared to the control group. There were no group differences for VTDS or realism ratings. Four participants from the control group exhibited outlier behavior with more pronounced phonotraumatic symptoms following performance than all other participants. CONCLUSIONS: VCT shows evidence of mitigating symptoms of dysphonia while preserving the realism of the vocal performance. More work is needed to understand performers at risk for more severe vocal symptoms following extreme voice-over work, so as to target them for preventative techniques and voice preservation.

Mitigating Dysphonia, Pain, and Vocal Handicap after Violent Video Game Voice Overs: A Pilot Investigation into Vocal Combat Technique Training.

OBJECTIVE: to investigate how the Vocal Combat Technique (VCT) may mitigate vocal symptoms in voice over actors using vocal violence. METHODS: Five voice over actors (3 male, 2 females, Mean = 29.6 years) completed two study sessions of 45 minutes-to-1 hour of vocally violent voice over work held approximately 4 weeks apart. During session one, participants completed voice over work as they typically would, whereas they received 3-hours of VCT training to improve/assist in healthy vocal techniques prior to session two. Pre- and post-session measures for both sessions included self-perceptual ratings of vocal symptoms, auditory-perceptual evaluation, and traditional acoustic measures of frequency and perturbation. RESULTS: Participants showed substantial mitigating effects of VCT training on acoustic perturbation measures (jitter, shimmer, harmonics-to-noise ratio), and self-ratings of vocal symptoms (Vocal-Handicap Index-10, McGill Pain Scale for vocal discomfort, and Evaluation of the Ability to Sing Easily) with calculated medium to large effect sizes (d = 0.61-1.95). There were no changes in auditory perceptual ratings across sessions. CONCLUSION: Our pilot investigation yielded positive improvements in vocal symptomology in five voice over actors who were trained in VCT. Next steps should include a larger enrollment of voice actors to determine optimal preventative and recovery techniques.

Predicting No Show in Voice therapy: Avoiding the Missed Appointment Cycle.

INTRODUCTION: Voice therapy plays a critical role in the treatment of voice disorders. Despite positive outcomes in patients who attend voice therapy, otolaryngologists, and speech-language pathologists continue to struggle with patient compliance. Previous studies evaluating the multidisciplinary clinic model have shown better completion, VHI-10 scores, and fewer cancelation and no-shows (NS). We sought to review our own patient experience to better identify factors that predict NS rates in voice therapy. METHODS: A retrospective chart review of patients at a tertiary medical center were included if they had a scheduled appointment during a 6-month period that was cancelled or a NS. Charts were reviewed for age, gender, race, diagnosis, number of sessions attended, reason for discharge, and attending physician. NS percentage is calculated as a ratio of number cancellations to total number sessions scheduled. A multivariable general linear model was used to examine the association between NS and the listed covariates. FINDINGS: The study included 146 patients mean (SD) age 52.7 (16.6), where 62% were female and 72.6% were white. There is evidence that not being seen in a multidisciplinary clinic is significantly associated with NS rates in voice therapy (χ2 = 4.09, P = 0.0431). There is also evidence that non-white race is significantly associated with NS rates in voice therapy (χ2 = 11.76, P = 0.0006). CONCLUSIONS: Data presented in this study further support the use of a multidisciplinary model to improve NS rates in voice therapy. The relationship between nonwhite patients and lower NS suggests another determining factor in nonadherence to voice therapy.