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A composite polymeric scaffold of gelatin/alginate /graphene is fabricated through freeze‐drying technique. Initially, a hydrogel system comprised of gelatin/alginate (1:1) is prepared, and then the effect of different amounts of graphene carboxyl nanosheets (1,1.5, 2, and 2.5 wt.%) on the resultant structural properties are thoroughly evaluated. The swelling ratio, biodegradability, electrical and mechanical properties of bio‐composite hydrogels are controlled by manipulating the concentration of graphene‐COOH. The significant increase in the electrical conductivity is observed with the addition of 2.5% graphene‐COOH, and the electrical conductivity increased from 8.525 × 10−7 ± 0.01 S cm−1 to 7.644 × 10−4 ± 0.04 S cm−1. Also, the biocomposite hydrogels exhibited compressive and tensile strength ranging from 25 to 382 KPa and 11.4 to 148 KPa with an increase in the concentration of graphene‐COOH. The simplicity, low cost, tunable mechanical properties, and optimal electrical conductivity of the hydrogel system presented in this study highlight its potential as nerve tissue replacement. [ABSTRACT FROM AUTHOR]

Calcium looping process is a promising approach for CO2 capture from the flue gas of fossil fuel power plants and the cement industry. Even though the advantages of calcium‐based sorbents are low cost and high uptake capacity, they suffer from low durability during cycles. Modified sorbents were fabricated by adding alumina and zirconia and the mixture of alumina and zirconia to calcium oxide via the co‐precipitation method. The performance of synthesized sorbents in terms of stability and CO2 capture capacity were evaluated using a fixed bed reactor in various CO2 sorption/desorption cycles. The sorbents were fabricated by a co‐precipitation methodology using 10% binders (alumina and/or silica). X‐ray diffraction (XRD), BET/BJH, and scanning electron microscopy (SEM) were conducted for characterization of synthesized sorbents. CaO‐10% ZrO2 showed the best performance among the fabricated sorbents in terms of stability during 5 cycles and CO2 capacity (14 mmol CO2/g sorbent). The formation of CaZrO3 with a perovskite structure and high‐temperature resistance could be attributed to well performance of zirconia‐supported sorbent. On the other hand, no sign of aluminum zirconate formation was approved in XRD analysis for the fabricated sorbent using mixed binders of zirconia and alumina to enhance its stability during cycles. [ABSTRACT FROM AUTHOR]

Background and Aim: Adding noise to the speech audiometry tests increases the sensitivity and specificity of them. This study aimed to investigate the normative data for the Speech-in-Noise (SIN) perception test in normal-hearing adults aged 18–25, and evaluate the effect of gender and ear laterality on the test score. Methods: In this cross-sectional study, 126 adults aged 18–25 years with mean(SD) of age: 22.28(1.61) years old participated. The SIN perception test using Persian monosyllabic words was performed in quiet and using 5 signal-to-noise ratios (SNRs; 0,± 5 and ± 10). Results: The mean of SIN perception score was 96.48, 91 and 82.79% at the SNRs of +10, +5, and 0 for the right ear, and 97.09, 91.42, and 84.11% at the SNRs of +10, +5, and 0 for the left ear, respectively. The interaction effect of gender and ear laterality had no statistically significant effect on the test results in quiet and at any SNRs (p>0.05). Moreover, the main effect of gender on the test score was not significant (p>0.05), and there was no significant difference in the test score between the right and left ears (p>0.05). Conclusion: Given the importance of including the SIN perception test in the routine audiology tests, considering normative data for this test is important. The normative data found in this study for this test can be routinely used in audiology clinics. [ABSTRACT FROM AUTHOR]