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The present study confirms that many children are aware of tinnitus and that they may be susceptible to stressful environments. In particular, trait anxiety may be associated with tinnitus. Because both tinnitus and anxiety can affect the daily lives and health of children-as with adults-a detailed strategy for the management of tinnitus in children should be established.

Hydrogels composed of N,N-dimethylacrylamide and a sulfonamide monomer (SDM, pK a = 6.17) derived from sulfadimethoxine exhibited a pH-induced volume-phase transition in water. This resulted from pH-dependent ionization/deionization of the sulfonamide group and reversible side group crystallization (physical cross-linking). The pH-dependent equilibrium swelling pattern was controlled by the polymer composition. At higher SDM content, a higher transition pH and a larger and sharper transition were observed, leading to almost discontinuous swelling transition of a gel containing 40 mol % SDM around the physiological pH. It is evident that side group crystallization was primarily responsible for such a sharp transition, influenced by temperature-induced chain flexibility and associated with hydrogen bonding between un-ionized sulfonamide groups. However, after crystal melting at 70 °C, the pH dependency in swelling was well-preserved but with reduced sharpness, suggesting a partial role of hydrophobic interaction in the pH-induced volume-phase transition.

New pH‐responsive polymers and hydrogel nanoparticles were synthesized, which bear either sulfapyridine or sulfamethoxypyridazine. The linear copolymers in water showed soluble/insoluble transition, while the hydrogel nanoparticles in aqueous solutions experienced association/dissociation transition in a narrow pH range. Their pH sensitivity was confirmed by the change in turbidity or particle size as a function of pH. The ionization of SO2NH group in sulfonamides is responsible for aggregation of the polymers or hydrogel nanoparticles. The transition pH is determined by the amount of SO2NH groups in the copolymers or on the hydrogel nanoparticle surface; at an optimum composition, the transitions occur near physiological pH. These systems may present a potential for various biomedical and bioengineering fields, such as pulsatile drug delivery, targeting, embolization, sensors, and bioseparation.

Slippage-induced artifacts are presumed to be because of the slingshot-like movement of the goggles during head movement in three different phases (lagging, overshooting, and bouncing of the goggles). Monitoring the pressure of the strap tightness may be a solution for minimizing this slippage. A strap tightness of at least 45 cm H2O is required for reliable vHIT recording and gain calculations.

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