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Purpose: The Chinese Sound Test (Hung, Lin, Tsai, & Lee, 2016) has been recently developed as a modified version of the Ling Six-Sound Test (Ling, 2012). By incorporating Chinese speech sounds, this test should be able to estimate whether the listener can hear across the Chinese speech spectrum. To establish the clinical validity of the test, this study examined the relationship between the aided audiometric thresholds and the distance thresholds. Method: Sixty children with bilateral hearing aids were recruited. The aided sound-field thresholds at 250,500,1000,2000,4000, and 6000 Hz were compared with the distance thresholds of six sounds, /u, 8,a, i, teh, and s/, which encompass the entire Chinese speech frequency range from low to high. Results: Partial correlation and stepwise regression analyses revealed that the Chinese testing sounds are frequency specific and that the audibility of each sound could be predicted by a specific frequency threshold. Conclusions: The results confirm the validity of the Chinese Sound Test, indicating that the testing sounds can be reliably used to assess the perception of frequency-specific information. Crucially, these data also demonstrate that the Chinese Sound Test is a useful tool to identify red flags of poor auditory access in daily environment to monitor device malfunctions and possible hearing fluctuations. [ABSTRACT FROM AUTHOR]

HA2-TAT is a peptide-based delivery agent that combines the pH-sensitive HA2 fusion peptide from influenza and the cell-penetrating peptide TAT from HIV. This chimeric peptide is engineered to induce the cellular uptake of macromolecules into endosomes via the TAT moiety and to respond to the acidifying lumen of endosomes to cause membrane leakage and release of macromolecules into cells via the HA2 moiety. The question of how HA2 and TAT affect the properties of one another remains, however, unanswered, and the behavior of the peptide inside endosomes is mostly uncharacterized. To address these issues, the binding and membrane leakage activity of a glutamic acid-enriched analogue E5-TAT was assessed with red blood cells and giant unilamellar vesicles as membrane models for endosomes. Hemolysis and microscopy assays reveal that E5-TAT binds to membranes in a pH-dependent manner and causes membrane leakage by inducing the formation of pores through which macromolecules can escape. The TAT moiety contributes to this activity by causing a shift in the pH response of E5 and by binding to negatively charged phospholipids. On the other hand, TAT binding to glycosaminoglycans reduces the lytic activity of E5-TAT. Addition of TAT to the C-terminus of E5 can therefore either increase or inhibit the activity of E5 depending on the cellular components present at the membrane. Taken together, these results suggest a model for the endosomolytic activity of the peptide and provide the basis for the molecular design of future delivery agents. [ABSTRACT FROM AUTHOR]

When fiber-reinforced plastic (FRP) crafts sail at high speed, very large slamming forces impact the bottom structures of crafts. Therefore, the capacity to resist these forces is an important factor when designing crafts. In the past, the instability and complexity of material properties in failure analysis, in addition to the difficulties in conducting the laminate failure experiments due to water impact, resulted in few studies investigating the failure progress of FRP laminates subjected to water impact. This study presents a novel impulsive water-pressure failure experimental system that combines a hydraulic system with a water-pressure failure experimental fixture used in previous work, to generate impulsive water pressure. Using this system, the FRP laminates are deformed and damaged under water impact. In numerical analysis, the finite element software ABAQUS and user subroutine user-defined field (USDFLD) are utilized to calculate the strain field of laminates as a basis of failure evaluation and stiffness degradation of a structure after specifying failure criteria and stiffness modification curve obtained from material tests for different materials. By comparison with experimental data, the numerical model can be validated, regardless of whether the impulsive water loads are sufficiently small or large to cause structure failure. Consequently, based on the results of this study, the abilities of analyzing the dynamic failure progress under out-of-plane impulsive water pressure and the corresponding experimental systems can be well established. Furthermore, the capacity of FRP laminates in resisting water pressure can also be elucidated. [ABSTRACT FROM AUTHOR]

The material and ply angles of a fiber-reinforced plastic (FRP) rotor blade of a helicopter are optimized using a genetic algorithm (GA) with local search. The variation of the structural stiffness with material and ply angle is investigated. The aim of the optimization is to find an optimal stacking sequence that minimizes twist deformation. An optimum rotor blade is obtained using the ply angles as variables; failure, natural frequency, and minimum moment of inertia are used to constrain the optimization. The GA is employed as an optimization tool. A simplified local search is implemented in the final stage of optimization to reduce the searching time. [ABSTRACT FROM AUTHOR]

This study examines the progressive failure of marine glass fiber-reinforced plastic (GFRP) laminates subjected to out-of-plane water pressure. First, experimental data concerning laminates that consist of a single type of fiber are used to establish the finite element model by separating the section into fiber layers and matrix layers. After a suitable failure criterion has been specified and the stiffness modification factor of different materials obtained experimentally, a numerical model is used to simulate the failure behavior of marine GFRP laminates. This numerical model is then applied to analyze the failure of GFRP ship bottom structures under water pressure. The water pressure failure experiment is designed to verify the numerical results. The experimental system includes a watertight cabin, which comprises the wall of the fixture, the specimen, and a movable piston, filled with water. Then, the water pressure is increased by moving the piston to compress the water-sealed zone, until the specimen reaches ultimate failure. After the numerical model has been validated, the abilities of testing and analyzing the failure behavior of laminates under static water pressure are established. More information is presented about the capacity to resist out-of-plane water pressure, the proper use of the material, and improving the efficiency of the design. [ABSTRACT FROM AUTHOR]

This work investigates the impact behavior of carbon--epoxy composite-laminated shells with three different curvatures. For the low-velocity impact cases, a quasi-static method is introduced to reduce the need for dynamic approaches. The static crushing information (force-displacement data) of the shell is critical to the quasi-static simulation. Based on the crushing data extracted from experiments or numerical simulations, numerous dynamic impact results for distinct impactor masses and velocities can be obtained immediately from a single static result, as long as these impacts are classified as low-velocity conditions. Static experiments and simulations are always more effective than dynamic ones. This investigation concludes that the quasi-static method delivers excellent exactitude, provided the static force-displacement data, the dominator, are accurately acquired. [ABSTRACT FROM AUTHOR]

A steel impactor was used in drop tests to impact composite laminated plates constructed using carbon-epoxy prepregs. The impact force and strain histories were recorded as well. Damage incurred from a low-velocity impact much closely resembled that from static crushing. This investigation creates a user-defined material subroutine (UMAT) of the FEM software ABAQUS, using our method of stiffness progressive modification, such that extreme failure is accurately simulated until the plates are thoroughly crushed. Using the results from the static crush simulation and the aspect of energy conservation, the dynamic impact force given with different impactor masses and initial velocities can be rapidly predicted while making significant savings in computing resources. [ABSTRACT FROM AUTHOR]

Presents a study which investigated a theoretical and numerical model to calculate the tensile and flexural Young's moduli in marine glass fiber-reinforced plastic laminates (GFRP). Description of Young's modulus of GFRP laminates; Application of the composite beam theory to actual marine GFRP laminates; Strength of GFRP laminates.

The article discusses the ability to deliver proteins across biological barriers that expands the therapeutic potential of protein-based drugs that also allow for experimental opportunities in basic research. It is suggested that a collection of delivery vectors (DV) that mediate the transfer of proteins across the plasma membrane has been discovered over the past decade.

Purpose: Because the Ling six-sound test is based on American English phonemes, it can yield unreliable results when administered to non-English speakers. In this study, we aimed to improve specifically the diagnostic palette for Mandarin Chinese users by developing an adapted version of the Ling six-sound test. Method: To determine the set of testing sounds, we performed an exhaustive acoustic and statistical analysis in which we considered not only the general acoustic properties but also the order of acquisition and the inter- and intraspeaker variability. Results: Six phonemes (/u, ə, a, i, tɕh, s/) were selected as the testing items for the Mandarin Chinese sound test because these sounds exhibit a highly compartmentalized frequency specificity, spanning the entire Chinese speech spectrum, as well as a relatively low articulatory variability and can be acquired fairly early. Conclusion: Through adopting language-dependent modifications, caregivers and professionals should have a more adequate tool to monitor children’s auditory access to the full range of Mandarin speech sounds. [ABSTRACT FROM AUTHOR]