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1.
World J Clin Cases ; 12(19): 3760-3766, 2024 Jul 06.
Article in English | MEDLINE | ID: mdl-38994283

ABSTRACT

BACKGROUND: Numerous studies have found that patients experiencing sudden sensorineural hearing loss (SSHL), with or without accompanying vertigo, often show impaired vestibular function. However, there is a dearth of studies analyzing vestibular-evoked myogenic potentials (VEMPs) in SSHL patients across various age groups. AIM: To investigate vestibular condition in SSHL patients across various age demographics. METHODS: Clinical data of 84 SSHL patients were investigated retrospectively. Audiometry, cervical vestibular evoked myogenic potentials (c-VEMPs), and ocular vestibular evoked myogenic potentials (o-VEMPs) were conducted on these patients. Parameters assessed included the latencies of P1 and N1 waves, as well as the amplitudes of P1-N1 waves. Moreover, the study evaluated the influence of factors such as sex, affected side, configuration of hearing loss, and presence of accompanying vertigo. RESULTS: Among the 84 SSHL patients, no significant differences were observed among the three groups in terms of gender, affected side, and the presence or absence of vertigo. Group II (aged 41-60 years) had the highest number of SSHL cases. The rates of absent o-VEMPs in the affected ears were 20.83%, 31.58%, and 22.72% for the three age groups, respectively, with no statistically significant difference among them. The rates of absent c-VEMPs in the affected ears were 8.3%, 34.21%, and 18.18% for the three age groups, respectively, with significant differences. In the unaffected ears, there were differences observed in the extraction rates of o-VEMPs in the unaffected ears among the age groups. In the three age groups, no significant differences were noted in the three age groups in the latencies of P1 and N1 waves or in the amplitude of N1-P1 waves for c-VEMPs and o-VEMPs, either on the affected side or on the unaffected side, across the three age groups. CONCLUSION: The extraction rate of VEMPs is more valuable than parameters. Regardless of the presence of vertigo, vestibular organs are involved in SSHL. Notably, SSHL patients aged 41-60 appear more susceptible to damage to the inferior vestibular nerve and saccule.

2.
Nanoscale ; 12(33): 17213-17221, 2020 Sep 07.
Article in English | MEDLINE | ID: mdl-32804990

ABSTRACT

Recently, the newly emerging lead-halide perovskites have received tremendous attention in the photodetection field because of their intrinsic large light absorption and high well-balanced carrier transport characteristics. Unfortunately, the issue of instability and the existence of toxic lead cations have greatly restricted their practical applications and future commercialization. Furthermore, the previous studies on perovskite photodetectors mainly operate in visible and near-infrared light region, and there are practically no relevant reports aimed at the deep-ultraviolet (DUV) region. In this study, an air-stable and DUV-sensitive photoconductive detector was demonstrated with a solution-processed ternary copper halides Cs3Cu2I5 thin films as the light absorber. The proposed photodetector is very sensitive to wavelengths of light below 320 nm and unresponsive to the visible light. Because of the high material integrity and large surface coverage of the Cs3Cu2I5 thin films, the detector presents an outstanding photodetection performance with a photoresponsivity of ∼17.8 A W-1, specific detectivity of 1.12 × 1012 Jones, and fast response speed of 465/897 µs, superior to previously reported DUV photodetectors based on other material systems. Unlike traditional lead-halide perovskites, the lead-free Cs3Cu2I5 shows remarkable stability against heat, UV light, and environmental oxygen/moisture. Thus, the unsealed photodetector demonstrates good operation stability for 11 h of continuous running in open air. Even after 80-day storage in ambient air, its photodetection capability can nearly be maintained. The results suggest that non-toxic Cs3Cu2I5 could be a potential candidate for stable and environment friendly DUV detectors, enabling an assembly of optoelectronic systems in the future.

3.
Nanoscale ; 8(19): 10035-42, 2016 May 21.
Article in English | MEDLINE | ID: mdl-27140056

ABSTRACT

Recently, perovskite-based light-emitting diodes based on organometal halide emitters have attracted much attention because of their excellent properties of high color purity, tunable emission wavelength and a low-temperature processing technique. As is well-known, organic light-emitting diodes have shown powerful capabilities in this field; however, the fabrication of these devices typically relies on high-temperature and high-vacuum processes, which increases the final cost of the product and renders them uneconomical for use in large-area displays. Organic/inorganic hybrid halide perovskites match with these material requirements, as it is possible to prepare such materials with high crystallinity through solution processing at low temperature. Herein, we demonstrated a high-brightness green light-emitting diode based on PEDOT: PSS/CH3NH3PbBr3/ZnO sandwich structures by a spin-coating method combined with a sputtering system. Under forward bias, a dominant emission peak at ∼530 nm with a low full width of half-maximum (FWHM) of 30 nm can be achieved at room temperature. Owing to the high surface coverage of the CH3NH3PbBr3 layer and a device design based on carrier injection and a confinement configuration, the proposed diode exhibits good electroluminescence performance, with an external quantum efficiency of 0.0645%. More importantly, we investigated the working stability of the studied diode under continuous operation to verify the sensitivity of the electroluminescence performance to ambient atmosphere and to assess the suitability of the diode for practical applications. Moreover, the underlying reasons for the undesirable emission decay are tentatively discussed. This demonstration of an effective green electroluminescence based on CH3NH3PbBr3 provides valuable information for the design and development of perovskites as efficient emitters, thus facilitating their use in existing applications and suggesting new potential applications.

4.
Nanoscale ; 8(19): 9997-10003, 2016 May 21.
Article in English | MEDLINE | ID: mdl-27142941

ABSTRACT

Semi-transparent all-oxide light-emitting diodes based on ZnO/NiO-core/shell nanowire structures were prepared on double-polished c-Al2O3 substrates. The entire heterojunction diode showed an average transparency of ∼65% in the ultraviolet and visible regions. Under forward bias, the diode displayed an intense ultraviolet emission at ∼382 nm, and its electroluminescence performance was remarkable in terms of a low emission onset, acceptable operating stability, and the ability to optically excite emissive semiconductor nanoparticle chromophores.

5.
Opt Express ; 20(5): 5636-43, 2012 Feb 27.
Article in English | MEDLINE | ID: mdl-22418371

ABSTRACT

A GaN/Si nanoheterostructure array was prepared by growing GaN nanostructures on silicon nanoporous pillar array (Si-NPA). Based on as-grown and annealed GaN/Si-NPA, two light-emitting diodes (LEDs) were fabricated. It was found that after the annealing treatment, both the turn-on voltage and the leakage current density of the nanoheterostructure varied greatly, together with the electroluminescence (EL) changed from a yellow band to a near infrared band. The EL variation was attributed to the radiative transition being transformed from a defect-related recombination in GaN to an interfacial recombination of GaN/Si-NPA. Ours might have provided an effective approach for fabricating GaN/Si-based LEDs with different emission wavelengths.


Subject(s)
Gallium/chemistry , Luminescent Measurements/instrumentation , Nanostructures/chemistry , Nanotechnology/instrumentation , Silicon/chemistry , Equipment Design , Equipment Failure Analysis , Hardness , Hot Temperature , Nanostructures/ultrastructure
6.
Nanotechnology ; 20(29): 295501, 2009 Jul 22.
Article in English | MEDLINE | ID: mdl-19567965

ABSTRACT

A patterned Ag structure was grown on a Si nanoporous pillar array (Si-NPA) by an immersion plating method, and its surface-enhanced Raman scattering (SERS) activity toward adenine was studied. It was shown that two kinds of Ag structures were grown on Si-NPA, a continuous film covering the Si-NPA substrate and composed of Ag nanocrystallites (nc-Ag), and a quasi-regular, interconnected network composed of loop-chains of sub-micron Ag crystallites surrounding the porous Si pillars. The SERS detection of low-concentration adenine solution was performed by using Ag/Si-NPA as active substrates, in which significantly enhanced Raman signals were observed. The SERS enhancement was attributed to the active spacing sites formed between the Ag particles and the nc-Ag which met the optimal size for causing a SERS effect. Based on the measured SERS spectra, the adsorption mode of adenine molecules on Ag particles was deduced. These results indicated that Ag/Si-NPA might be a promising active substrate for SERS detection of low-concentration bio-molecules.


Subject(s)
Adenine/chemistry , Metal Nanoparticles/chemistry , Silicon/chemistry , Silver/chemistry , Spectrum Analysis, Raman/methods , Microscopy, Electron, Scanning , Models, Chemical , Surface Properties , X-Ray Diffraction
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