Background and Purpose-Acute ischemic stroke in the distribution of the anterior inferior cerebellar artery (AICA) is known to be associated with vertigo, nystagmus, facial weakness, and gait ataxia. Few reports have carefully examined the deafness associated with the AICA infarction. Furthermore, previous neurological reports have not emphasized the inner ear as a localization of sudden deafness. The aim of this study was to investigate the incidence of deafness associated with the AICA infarction and the sites predominantly involved in deafness. Methods-Over 2 years, we prospectively identified 12 consecutive patients with unilateral AICA infarction diagnosed by brain MRI. Pure-tone audiogram, speech discrimination testing, stapedial reflex testing, and auditory brainstem response were performed to localize the site of lesion in the auditory pathways. Electronystagmography was also performed to evaluate the function of the vestibular system. Results-The most common affected site on brain MRI was the middle cerebellar peduncle (nϭ11). Four patients had vertigo and/or acute auditory symptoms such as hearing loss or tinnitus as an isolated manifestation from 1 day to 2 months before infarction. Audiological testings confirmed sensorineural hearing loss in 11 patients (92%), predominantly cochlear in 6 patients, retrocochlear in 1 patient, and combined on the affected side cochlear and retrocochlear in 4 patients. Electronystagmography demonstrated no response to caloric stimulation in 10 patients (83%). Conclusions-In our series, sudden deafness was an important sign for the diagnosis of AICA infarction. Audiological examinations suggest that sudden deafness in AICA infarction is usually due to dysfunction of the cochlea resulting from ischemia to the inner ear.

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Gold-decorated block copolymer microspheres (BCP-microspheres) displaying various surface morphologies were prepared by the infiltration of Au precursors into polystyrene-b-poly(4-vinylpyridine) (PS-b-P4VP) microspheres. The microspheres were fabricated by emulsifying the PS-b-P4VP polymers in chloroform into a surfactant solution in water, followed by the evaporation of chloroform. The selective swelling of the P4VP domains in the microspheres by the Au precursor under acidic conditions resulted in the formation of Au-decorated BCP-microspheres with various surface nanostructures. As evidenced by transmission electron microscopy (TEM) and scanning electron microscopy (SEM) measurements, dotted surface patterns were formed when microspheres smaller than 800 nm were synthesized, whereas fingerprint-like surface patterns were observed with microspheres larger than 800 nm. Au nanoparticles (NPs) were located inside P4VP domains near the surfaces of the prepared microspheres, as confirmed by TEM. The optical properties of the BCP-microspheres were characterized using UV-vis absorption spectroscopy and fluorescence lifetime measurements. A maximum absorption peak was observed at approximately 580 nm, indicating that Au NPs are densely packed into P4VP domains on the microspheres. Our approach for creating Au-NP-hybrid BCP-microspheres can be extended to other NP systems such as iron-oxide or platinum NPs. These precursors can also be selectively incorporated into P4VP domains and induce the formation of hybrid BCP-microspheres with controlled surface nanostructures.

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Triboelectric nanogenerators are aspiring energy harvesting methods that generate electricity from the triboelectric effect and electrostatic induction. This study demonstrates the harvesting of wind energy by a wind-rolling triboelectric nanogenerator (WR-TENG). The WR-TENG generates electricity from wind as a lightweight dielectric sphere rotates along the vortex whistle substrate. Increasing the kinetic energy of a dielectric converted from the wind energy is a key factor in fabricating an efficient WR-TENG. Computation fluid dynamics (CFD) analysis is introduced to estimate the precise movements of wind flow and to create a vortex flow by adjusting the parameters of the vortex whistle shape to optimize the design parameters to increase the kinetic energy conversion rate. WR-TENG can be utilized as both a self-powered wind velocity sensor and a wind energy harvester. A single unit of WR-TENG produces open-circuit voltage of 11.2 V and closed-circuit current of 1.86 μA. Additionally, findings reveal that the electrical power is enhanced through multiple electrode patterns in a single device and by increasing the number of dielectric spheres inside WR-TENG. The wind-rolling TENG is a novel approach for a sustainable wind-driven TENG that is sensitive and reliable to wind flows to harvest wasted wind energy in the near future.

We report the properties of a hydrogen (H2) gas sensor based on platinum (Pt)-coated carbon nanotubes (CNTs) in this paper. To fabricate the Pt-CNT composite sensor, a highly aligned CNT sheet was prepared on a glass substrate from a spin-capable CNT forest, followed by electrobeam (e-beam) deposition of Pt layers onto the CNT sheet. To investigate the effect of Pt on the response of the sensor, Pt layers of different thicknesses were deposited on the CNT sheets. A Pt thickness of 6 nm yielded the highest response for H2 detection, whereas Pt layers thinner or thicker than 6 nm led to a reduction of the surface area for gas adsorption and, consequently, decreased response. The Pt-CNT composite sensor detects H2 concentrations of 3-33% at room temperature and shows reproducible behavior with fast response and recovery times.

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High strain biocompatible polydimethylsiloxane-based conductive graphene and multiwalled carbon nanotube nanocomposite strain sensors Appl. Phys. Lett. 102, 183511 (2013); 10.1063/1.4804580Graphene wrapped multiwalled carbon nanotubes dispersed nanofluids for heat transfer applications This paper reports highly flexible, transparent, conducting heaters based on multiwalled carbon nanotube (MWCNT) sheets. The MWCNT sheets were spun directly from a well-aligned MWCNT forest. The fabrication of the MWCNT sheet heater was quite simple and suitable for mass production, requiring only a one-step transferring process, in which the MWCNT sheet is drawn onto the target substrates. This study examined the parameters that affect the heat generation of the MWCNT sheet-based heater; input power, surface area, and thermal conductivity of the substrate. In particular, more effort was focused on how to increase the surface area and contact points between the individual MWCNTs; simple acid treatment and added metal nanoparticles increased the heat performance of the heater dramatically. Moreover, the heaters exhibited durability and flexibility against many bending cycles. Therefore, the MWCNT sheet-based heater can be used for versatile applications requiring transparency, conduction, and flexibility.