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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]

Reflective functioning is the process of reflecting on the thoughts and feelings of oneself and others and is foundational to healthy human relationships. The 54-item Reflective Function Questionnaire (RFQ) is a self-report measure that assesses reflective functioning, initially developed while studying individuals with borderline personality disorder (BPD). The purpose of the present study was to translate the RFQ from English to Persian and evaluate its reliability and validity among Iranian prisoners. The sample of this study included 509 (455 men and 54 women) Iranian prisoners. Findings confirm the translated measure had acceptable face and content validity. A confirmatory factor analysis (CFA) confirmed two dimensions of certainty (RFQ-c) and uncertainty (RFQ-u) of reflective functioning. The correlation analysis showed positive relationships between the dimensions of the RFQ and the borderline personality symptoms questionnaire and the emotional dissatisfaction questionnaire. Correlation analysis also showed negative associations between the dimensions of the RFQ and the Toronto Basic Empathy Scale (BES) and the Kentucky Inventory of Mindfulness Skills (KIMS) questionnaire, confirming the concurrent validity of the RFQ. The Cronbach's alphas of the RFQ-c and RFQ-u subscales were.69 and.7 respectively, which demonstrated relatively acceptable internal consistency. The results of the analysis demonstrated that the translated RFQ had desirable psychometric properties for evaluating reflective function among Iranian prisoners. [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]

Obstruction of fluid flow by stationary bubbles in a microchannel hemodialyzer decreases filtration performance and increases damage to blood cells through flow maldistribution. A polyethylene oxide (PEO)-polybutadiene (PB)-polyethylene oxide surface modification, previously shown to reduce protein fouling and water/air contact angle in polycarbonate microchannel hemodialyzers, can improve microchannel wettability and may reduce bubble stagnation by lessening the resistive forces that compete with fluid flow. In this study, the effect of the PEO-PB-PEO coating on bubble retention in a microchannel array was investigated. Polycarbonate microchannel surfaces were coated with PEO-PB-PEO triblock polymer via radiolytic grafting. Channel obstruction was measured for coated and uncoated microchannels after injecting a short stream of air bubbles into the device under average nominal water velocities of 0.9 to 7.2 cm/s in the channels. The presence of the PEO coating reduced obstruction of microchannels by stationary bubbles within the range of 1.8 to 3.6 cm/s, average nominal velocity. Numerical simulations based on the lattice Boltzmann method indicate that beneficial effects may be due to the maintenance of a lubricating, thin liquid film around the bubble. The determined effective range of the PEO coating for bubble management serves as an important design constraint. These findings serve to validate the multiutility of the PEO-PB-PEO coating (bubble lubrication, biocompatibility, and therapeutic loading). © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 941-948, 2016. [ABSTRACT FROM AUTHOR]

This paper highlights the influence of contact line (pinning) forces on the mobility of dry bubbles in microchannels. Bubbles moving at velocities less than the dewetting velocity of liquid on the siuface are essentially dry, meaning that there is no thin liquid film around the bubbles. For these "dry" bubbles, contact line forces and a possible capillary pressure gradient induced by pinning act on the bubbles and resist motion. Without sufficient driving force (e.g., external pressure), a dry bubble is brought to stagnation. For the first time, a bipartite theoretical model that estimates the required pressure difference across the length of stagnant bubbles with concave and convex back interfaces to overcome the contact line forces and stimulate motion is proposed. To validate our theory, the pressure required to move a single diy bubble in square microchannels exhibiting contact angle hysteresis has been measured. The working fluid was de-ionized water. The experiments have been conducted on coated glass channels with different surface hydro-philicities that resulted in concave and convex back interfaces for the bubbles. The experimental results were in agreement with the model's predictions for square channels. The predictions of the concave and convex back models were within 19% and 27% of the experimental measurements, respectively. [ABSTRACT FROM AUTHOR]