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Objective:To establish the normal values of subjective visual horizontalï¼SVHï¼ under different head tilt angles, analyze the test-retest reliability, and provide a normal value reference for the refined diagnosis and functional assessment of SVH in clinical vestibular disorders. Methods:Thirty-one healthy young people were selected to wear visual reality glasses to test SVH data in five different head tilt angles: upright head position 0°, head tilted 45°to the leftï¼L45°ï¼, head tilted 45° to the rightï¼R45°ï¼, head tilted 90° to the leftï¼L90°ï¼, and head tilted 90° to the rightï¼R90°ï¼, and were re-tested 2 weeks later. Results:â The normal values of SVH at 0°, L45°, R45°, L90°, and R90°were 0.30±1.32, 5.94±5.54, -11.44±5.32, -0.87±8.63, -2.70±8.02, respectively. â¡The 95% confidence intervals of SVH at 0°, L45°, R45°, L90°, and R90° were: ï¼-2.34,2.94ï¼,ï¼-5.14,17.02ï¼,ï¼-22.08,-0.80ï¼,ï¼-18.13,16.39ï¼,ï¼-18.74ï¼13.34ï¼, respectively. The ratio of asymmetry in the absolute value of bilateral 45° deviation was 26.4% and the ratio of asymmetry in the absolute value of bilateral 90° deviation was 1.3%. â¢The intra-class correlation coefficientï¼ICCï¼ for 0°, L45°, R45°, L90° and R90° was 0.625, 0.641, 0.564, 0.769, 0.656, respectively. Conclusion:SVH has good test-retest reliability and high clinical test stability and stability. The data on normal values of SVH at different head tilt angles established in this study can provide clinical references for the refined diagnosis and functional assessment of vestibular system disorders.
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Cabeza , Humanos , Adulto Joven , Masculino , Reproducibilidad de los Resultados , Femenino , Valores de Referencia , Adulto , Postura , Voluntarios Sanos , Pruebas de Función Vestibular/métodosRESUMEN
Asymmetric doping of wide-gap semiconductors has long been a major challenge, hindering their wider applications. Despite numerous attempts to address this issue through engineering doping levels, the results were still inconclusive. In this work, we propose a quantum engineering strategy based on the state-of-the-art spin-polarized HSE06 hybrid functional method. The local band offset between the host and quantum structures can considerably compensate for the large carrier activation energy (Ea). We chose the system of the AlN host embedded by GaN quantum dots as an example to validate the feasibility of this strategy. The Ea of Si (n-type) and Be (p-type) dopants can be reduced from 222 and 404 meV to negative values and 2 meV, respectively. Therefore, electron and hole density can be increased to more than 1019 and 1020 cm-3, respectively. We also tested potential dopants (C and Ge for the n-type, Mg and Ca for the p-type), and the technique is equally effective. This mechanism can also be used to understand the experimental observations of the superlattice doping strategy. Overall, our study demonstrates that the quantum engineering strategy provides a potential solution to overcome the asymmetric doping problem for universal wide-gap semiconductors and supports a feasible pathway for more efficient devices in the future.
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Objective:To establish the normal values of subjective visual vertical ï¼SVVï¼ in different head deflection angles and analyze its test and retest reliability, in order to provide a reference for the clinical application of SVV in the evaluation of vestibular disorders. Methods:Thirty-one healthy young people were selected to wear VR glasses, and the SVV data were tested in five different head-tilt, namely, 0° in the upright head position, 45°in the left head position, 45° in the right head position, 90° in the left head position, and 90° in the right head position, and were re-tested 2 weeks later. Results:â The mean values of SVV at 5 different head-tilt angles of 0°, left 45°, right 45°, left 90°, and right 90° were -0.07±1.71, 4.30±5.39, -6.51±5.58, -3.76±7.42, and 0.40±8.02, respectively, The 95% confidence limits of SVV at 0°, left 45°, right 45°, left 90°, right 90°, and right 90° were ï¼-3.42, 3.28ï¼, ï¼-6.26, 14.86ï¼, ï¼-17.45, 4.43ï¼, ï¼-18.30, 10.78ï¼, andï¼-15.32, 16.12ï¼, respectively; â¡The absolute values of SVV at 4 different head-tilt angles of left 45°, right 45°, left 90°, and right 90° were 5.62±3.96, 6.90±5.07, 6.82±4.70 and 6.48±4.68, respectively. The 95% confidence limits of SVV at left 45°, right 45°, left 90°, right 90°, and right 90° wereï¼0ï¼12.11ï¼,ï¼0ï¼15.21ï¼,ï¼0ï¼14.53ï¼andï¼0ï¼14.16ï¼, respectively. The asymmetry ratio is 10% for the absolute value of the 45 ° deviation and 3% for the absolute value of the 90° deviation; â¢Intra-class correlation coefficientsï¼ICCï¼ for 0°, left 45°, right 45°, left 90°, right 90°were 0.757, 0.673, 0.674, 0.815, and 0.856, respectively. Conclusion:SVV has good retest reliability and high stability, and the SVV normal value data of different head deviation angles established in the present study can be used as a reference for the diagnosis and evaluation of vestibular disorders.
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Cabeza , Humanos , Reproducibilidad de los Resultados , Adulto Joven , Masculino , Femenino , Adulto , Postura , Enfermedades Vestibulares/diagnóstico , Valores de Referencia , Pruebas de Función Vestibular/métodosRESUMEN
Transition metal disulfide compounds (TMDCs) emerges as the promising candidate for new-generation flexible (opto-)electronic device fabrication. However, the harsh growth condition of TMDCs results in the necessity of using hard dielectric substrates, and thus the additional transfer process is essential but still challenging. Here, an efficient strategy for preparation and easy separation-transfer of high-uniform and quality-enhanced MoS2 via the precursor pre-annealing on the designed graphene inserting layer is demonstrated. Based on the novel strategy, it achieves the intact separation and transfer of a 2-inch MoS2 array onto the flexible resin. It reveals that the graphene inserting layer not only enhances MoS2 quality but also decreases interfacial adhesion for easy separation-transfer, which achieves a high yield of ≈99.83%. The theoretical calculations show that the chemical bonding formation at the growth interface has been eliminated by graphene. The separable graphene serves as a photocarrier transportation channel, making a largely enhanced responsivity up to 6.86 mA W-1, and the photodetector array also qualifies for imaging featured with high contrast. The flexible device exhibits high bending stability, which preserves almost 100% of initial performance after 5000 cycles. The proposed novel TMDCs growth and separation-transfer strategy lightens their significance for advances in curved and wearable (opto-)electronic applications.
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Carbon dots (CDs) have received considerable attention in many application areas owing to their unique optical properties and potential applications; however, the fluorescent mechanism is an obstacle to their applications. Herein, three-color emissive CDs are prepared from single o-phenylenediamine (oPD) by regulating the ratio of ethanol and dimethylformamide (DMF). Fluorescent mechanism of these CDs is proposed as molecular state fluorescence. Reaction intermediates are identified using liquid chromatrography-mass spectroscopy (LC-MS) and 1H nuclear magnetic resonance (NMR) spectra. 1H-Benzo[d]imidazole (BI), 2,3-diaminophenazine (DAP), and 5,14-dihydroquinoxalino[2,3-b] phenazine (DHQP) are proposed to be the fluorophores of blue, green, and red emissive CDs by comparing their optical properties. As per the LC-MS and 1H-NMR analysis, DHQP with red emission tends to form from DAP and oPD in pure ethanol. By adding DMF, BI formation is enhanced and DHQP formation is suppressed. The prepared CDs exhibit green emission with DAP. When the DMF amount is >50%, BI formation is considerably promoted, resulting in DAP formation being suppressed. BI with blue emission then turns into the fluorophore of CDs. This result provides us an improved understanding of the fluorescent mechanism of oPD-based CDs, which guides us in designing the structure and optical properties of CDs.
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Objective: To investigate the associations between cognition, anxiety, depression, and residual dizziness after successful repositioning maneuvers in the elderly with benign paroxysmal positional vertigo (BPPV). Methods: We enrolled 40 elderly patients with BPPV in our outpatient department. We used the Dizziness Handicap Inventory (DHI), Visual Analog Scale (VAS), Patient Health Questionnaire-9 (PHQ-9), and Generalized Anxiety Disorder Questionnaire-7 (GAD-7) to assess the degree of dizziness, anxiety, and depression of participants before repositioning therapy, respectively. At the 1-week follow-up after BPPV treatment, each participant will be reassessed and divided into a group with residual dizziness (RD) and a group without residual dizziness (NRD) based on the follow-up DHI score. The Mini-Mental State Examination (MMSE) evaluated the cognitive function of the participants. Results: The age, gender, duration of BPPV, and involved semicircular canals in the two groups did not show a significant difference. The RD group scored significantly higher on the DHI (p = 0.006), GAD-7 (p < 0.001), and PHQ-9 (p = 0.002) before the repositioning treatment than the NRD group. The two groups had no significant difference in MMSE score (p = 0.381). Anxiety and depression scores before repositioning treatment significantly and positively correlated with follow-up DHI scores (r = 0.678 and 0.522, respectively), but the MMSE score did not significantly relate to it. The univariate linear regression showed that the DHI (p < 0.001), GAD-7 (p < 0.001), and PHQ-9 (p = 0.002) scores before treatment could predict residual dizziness. The multivariate linear regression showed that GAD-7 before treatment was the only significant predictor of residual dizziness (p < 0.001). Conclusion: The level of dizziness, anxiety, and depression before treatment can predict residual dizziness after successful repositioning maneuvers in the elderly with BPPV. Anxiety may be the strongest predictor of residual dizziness after successful repositioning treatment in elderly BPPV patients.
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OBJECTIVE: Our aim was to determine the correlation between cognitive impairment and P300 event-related potential (ERP) in older adults with vertigo and imbalance, which further provides a reference for clinical diagnosis and patients' rehabilitation. METHODS: A total of 79 older adult patients with vertigo and imbalance in our outpatient department from January 2022 to December 2022 were selected and divided into the mild group (n = 20), moderate group (n = 39), and severe group (n = 20) according to the Dizziness Handicap Inventory (DHI). The auditory P300 component of event-related potentials (ERPs), Generalized Anxiety Disorder Questionnaire-7 (GAD-7), Patient Health Questionnaire-9 (PHQ-9), and Mini-Mental State Examination (MMSE) were used to evaluate depression, anxiety, and cognitive function in these patients, respectively. RESULTS: The P300 latencies of the different severity groups were 292 ± 10 ms, 301 ± 8 ms, and 328 ± 5 ms, respectively, and the differences were statistically significant (p = 0.010). The P300 amplitudes of the different severity groups were 14.4 ± 2.6 µV, 3.9 ± 0.8 µV, and 5.1 ± 1.4 µV, respectively, and the differences were also statistically significant (p = 0.004). There was no statistically significant difference in the DHI evaluation or VAS visual simulation scoring between the two groups (p = 0.625, and 0.878, respectively). Compared with the short-course group, the long-course group showed prolonged P300 latency and decreased amplitude, higher scores in PHQ-9 and GAD-7, and lower scores in MMSE, and all the differences were statistically significant (p = 0.013, 0.021, 0.006, 0.004, and 0.018, respectively). CONCLUSION: Older patients with more severe symptoms of vertigo and imbalance are at higher risk of developing abnormal cognitive function. The P300 can be used as an objective neurophysiological test for the assessment of cognitive function relevant to elderly patients with vertigo and imbalance.
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Background: The cause of idiopathic sudden sensorineural hearing loss (ISSNHL) remains unknown. It has been found that the functional status of the vestibular otolith is relevant to its prognosis; however, the evaluation of the vestibular otolith (intra-labyrinth) and superior and inferior vestibular nerve pathways (retro-labyrinth) in ISSNHL patients is not well-documented. Objective: This study aimed to investigate the functional status of the vestibular otolith and conductive pathway in patients with unilateral ISSNHL and analyze the correlations between vestibular evoked myogenic potentials (VEMPs) and hearing improvement after treatment. Methods: A total of 50 patients with unilateral ISSNHL underwent a battery of audio-vestibular evaluations, including pure tone audiometry, middle ear function, air-conducted sound-cervical VEMP (ACS-cVEMP), ACS-ocular VEMP (ACS-oVEMP), galvanic vestibular stimulation-cervical VEMP (GVS-cVEMP), and GVS-ocular VEMP (GVS-oVEMP). The results of auditory and VEMPs were retrospectively analyzed. Results: The abnormal rates of ACS-cVEMP, ACS-oVEMP, GVS-cVEMP, and GVS-oVEMP in affected ears were 30, 52, 8, and 16%, respectively. In affected ears, the abnormal rate of ACS-oVEMP was significantly higher than that of ACS-cVEMP (p = 0.025), while it was similar between GVS-cVEMP and GVS-oVEMP (p = 0.218). Compared with GVS-cVEMP, affected ears presented with a significantly higher abnormal rate of ACS-cVEMP (p = 0.005), and the abnormal rate of ACS-oVEMP was significantly higher than that of GVS-oVEMP (p < 0.001). No significant difference existed in latency and amplitude between affected and unaffected ears in ACS-VEMPs or GVS-VEMPs (p > 0.05). The abnormal rate of VEMPs in the poor recovery group was significantly higher than that of the good recovery group (p = 0.040). The abnormality percentages of ACS-oVEMP and GVS-oVEMP in the poor recovery group were significantly higher than that of the good recovery group (p = 0.004 and 0.039, respectively). The good hearing recovery rates were 76.47% in the normal VEMPs group, 58.33% in the intra-labyrinth lesion group, and 22.22% in the retro-labyrinth lesion group. Hearing recovery worsened as a greater number of abnormal VEMPs was presented. Conclusion: Besides Corti's organ, the impairment of otolithic organs was prominent in patients with ISSNHL. The normal VEMPs group had the highest rate of good recovery, followed by the intra-labyrinth lesion group and the retro-labyrinth lesion group presented with the lowest recovery rate. Abnormalities in ACS-oVEMP and/or GVS-oVEMP were indicators of a poor prognosis.
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Insightful understanding of defect properties and prevention of defect damage are among the biggest issues in the development of photoelectronic devices based on wide-gap III-nitride semiconductors. Here, we have investigated the vacancy-induced carrier nonradiative dynamics in wide-gap III-nitrides (GaN, AlN, and AlxGa1-xN) by ab initio molecular dynamics and nonadiabatic (NA) quantum dynamics simulations since the considerable defect density in epitaxy samples. E-h recombination is hardly affected by Vcation, which created shallow states near the VBM. Our findings demonstrate that VN in AlN creates defect-assisted nonradiative recombination centers and shortens the recombination time (τ) as in the Shockley-Read-Hall (SRH) model. In GaN, VN improves the NA coupling between the CBM and the VBM. Additionally, increasing x in the AlxGa1-xN alloys accelerates nonradiative recombination, which may be an important issue in further improving the IQE of high Al-content AlxGa1-xN alloys. These findings have significant implications for the improvement of wide-gap III-nitrides-based photoelectronic devices.
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Cross rolling process is a new method to manufacture large-diameter gears, which has great advantages. While during the gear manufacturing process with cross rolling, due to the difference of deformation mechanism between the right and left formed tooth profiles, a tip is pulled at the tooth top of the workpiece, which severely affects the forming quality. To eliminate the occurred defect, the finishing roller is proposed and designed, the motion equation of the finishing roller is established and solved, the principle of the height increase of the formed tooth is obtained. And also a simplified finite element (FE) model with finishing roller and non-finishing roller are established in the DEFORM-3D software. The comparison of the simulation results between two situations is analyzed and can be concluded that with the finishing roller, the protrusions at both sides of the tooth top of the workpiece at each stage are flattened by the finishing roller, and the accumulation of the tooth top protrusions is not going to occur, which means no extrusion and finishing of the tooth top of the workpiece are required. In addition, the experiment with the finishing roller is carried out and the effectiveness of the finishing roller can be verified.
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Background: Severe and profound idiopathic sudden sensorineural hearing loss (ISSNHL) generally leads to unfavorable prognosis, and has a considerable impact on patient quality of life. However, related prognostic factors remain controversial. Objective: To elaborate the relationship between vestibular function impairment and the prognosis of patients with severe and profound ISSNHL, and investigated the relevant factors affecting prognosis. Methods: Forty-nine patients with severe and profound ISSNHL were divided into good outcome group [GO group, pure tone average (PTA) improvement > 30 dB] and poor outcome group (PO group, PTA improvement ≤ 30 dB) according to hearing outcomes. The clinical characteristics and the proportion of abnormal vestibular function tests in these two groups were analyzed by univariate analysis, and multivariable logistic regression analysis was performed for parameters with significant differences. Results: Forty-six patients had abnormal vestibular function test results (46/49, 93.88%). The number of vestibular organ injuries was 1.82 ± 1.29 in all patients, with higher mean numbers in PO group (2.22 ± 1.37) than in GO group (1.32 ± 0.99). Univariate analysis revealed no statistical differences between the GO and PO groups in terms of gender, age, side of the affected ear, vestibular symptoms, delayed treatment, instantaneous gain value of horizontal semicircular canal, regression gain value of vertical semicircular canal, abnormal rates of oVEMP, cVEMP, caloric test and vHIT in anterior and horizontal semicircular canal, however, significant differences were found in the initial hearing loss and abnormal vHIT of posterior semicircular canal (PSC). Multivariable analysis revealed that only PSC injury was an independent risk factor for predicting the prognosis of patients with severe and profound ISSNHL. Patients with abnormal PSC function had worse initial hearing impairment and prognosis than patients with normal PSC function. The sensitivity of abnormal PSC function in predicting poor prognosis in patients with severe and profound ISSNHL was 66.67%, specificity was 95.45%, and positive and negative likelihood ratios were 14.65 and 0.35, respectively. Conclusion: Abnormal PSC function is an independent risk factor for poor prognosis in patients with severe and profound ISSNHL. Ischemia in the branches of the internal auditory artery supplying the cochlea and PSC may be the underlying mechanism.
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Objective: The present study aimed to investigate the status of vestibular function in children with vestibular migraine of childhood (VMC) reflected by vestibular function test battery and explore the pathophysiological implication of these instrument-based findings. Methods: The clinical data of 22 children (mean age 10.7 ± 2.9 years) with VMC who met the diagnostic criteria of the Barany Society were collected from September 2021 to March 2022. A vestibular function test battery on these children included a caloric test, video head impulse test (vHIT), cervical vestibular-evoked myogenic potential (cVEMP), and ocular vestibular-evoked myogenic potential (oVEMP); these parameters were triggered by air-conducted sound (ACS) and galvanic vestibular stimulation (GVS). The subjects were further divided into two groups: <3 months and >3 months according to the disease duration from symptom onset. The functional abnormalities and their characteristics reflected by the vestibular test battery, as well as the outcomes in children with or without aura, were analyzed. Results: (1) The abnormal rate of the caloric test was 15.8% and that of vHIT was 0%. The response rates of ACS-cVEMP and ACS-oVEMP were 100% and 90.5%, respectively. The response rates of GVS-cVEMP and GVS-oVEMP were 100% and 88.9%, respectively. (2) No statistical difference was observed in the abnormal rate of the caloric test (P = 0.55) and the response rate of ACS-oVEMP (P = 0.21) between the two groups, irrespective of the course duration. (3) No statistical difference was detected in the abnormal rate of the caloric test (P = 0.53) and the response rate of ACS-oVEMP (P = 1.00) in children with or without aura. Conclusion: Vestibular function status comprehensively reported by the vestibular test battery did not show an aggravation with the disease duration in children with VMC. Also, it was not affected by the existence of aura in children with VMC. The high abnormal rates of the caloric test and oVEMPs (ACS-oVEMP and GVS-oVEMP) suggested that the lateral semicircular canal (low-frequency function component), the utricle, and the superior vestibular conduction pathway might be involved in VMC.
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Objective: We compared the characteristics of air-conducted sound cervical vestibular evoked myogenic potential (ACS-cVEMP) and bone-conducted vibration cVEMP (BCV-cVEMP) among 3-month-old infants with normal hearing and sensorineural hearing loss (SNHL), and healthy adults to explore the feasibility and optimal strategies for infant vestibular screening. Methods: 29 infants (58 ears) were divided into two groups according to hearing (group I: normal hearing ears; group II: SNHL ears), 20 healthy adults were defined as group III. The results of response rate, P13 and N23 latency, P13-N23 interval, amplitudes, and corrected interaural asymmetry ratio (IAR) were recorded and compared among three groups. Results: The response rates of ACS-cVEMP in three groups were 88.89, 62.00, 100%, respectively. The P13 and N23 latencies, and P13-N23 interval did not differ significantly between group I and II (p = 0.866, p = 0.190, p = 0.252). A significant difference was found between group I and III (p = 0.016, p < 0.001, p < 0.001). No significant difference was observed in raw or corrected amplitude between group I and II (p = 0.741, p = 0.525), while raw and corrected amplitudes in group III were significantly larger than group I (p < 0.001, p < 0.001). For BCV-cVEMP, the response rates in three groups were 100, 86.36, 100%, respectively, No significant difference existed in the P13 and N23 latency, or P13-N23 interval between group I and II (p = 0.665, p = 0.925, p = 0.806), however, P13 and N23 latencies were significantly longer in group III than group I (p < 0.001, p = 0.018), but not in P13-N23 interval (p = 0.110). There was no significant difference in raw or corrected amplitude between group I and II (p = 0.771, p = 0.155) or in raw amplitude between group I and III (p = 0.093), however, a significant difference existed in corrected amplitude between group I and III (p < 0.001). Conclusions: Compared with adults, 3-month-old infants with normal hearing presented with equivalent response rates, shorter P13 and N23 latencies, smaller corrected amplitudes, and a wider IAR range for both ACS and BCV-cVEMP. SNHL infants had equivalent response rates of BCV-cVEMP, lower response rates of ACS-cVEMP than normal hearing infants. When responses were present, characteristics of ACS and BCV-cVEMP in SNHL infants were similar with normal hearing infants. ACS combined with BCV-cVEMP are recommended to improve the accuracy of vestibular screening.
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Objective: This study aims to investigate the potential vestibular pathway impairment through vestibular evoked myogenic potentials (VEMPs) and to explore the pathophysiological significance of these instrument-based findings in children with recurrent vertigo. Materials and methods: The clinical data of 21 children (mean age 4.67 ± 1.39 years) diagnosed as RVC who met the inclusion criteria of the Bárány Society and 29 healthy children (mean age 4.83 ± 1.34 years) enrolled as the control group from February 2021 to December 2021 were collected and analyzed retrospectively. All the subjects underwent both cervical VEMP (cVEMP) and ocular VEMP (oVEMP) triggered by air-conducted sound (ACS) and galvanic vestibular stimulation (GVS), respectively. The elicit rate, latency, and amplitude asymmetry ratio (AAR) of ACS-cVEMP, ACS-oVEMP, GVS-cVEMP, and GVS-oVEMP were analyzed. Results: (1) The elicit rates of ACS-cVEMP and ACS-oVEMP were similar in the two groups (P > 0.05), as well as GVS-cVEMP and GVS-oVEMP (P > 0.05). (2) P1 and N1 latencies of ACS-cVEMP and GVS-cVEMP in the RVC group were longer than those in the control group (P < 0.05). (3) The N1 latency of ACS-oVEMP in the RVC group was shorter than that in the control group (P < 0.05), while there was no significant difference in the P1 latency of ACS-oVEMP (P > 0.05). The N1 and P1 latencies of GVS-oVEMP were not significantly different (P > 0.05). (4) There was no statistical difference in the AAR of ACS-cVEMP and GVS-cVEMP. Although there was an increased AAR of ACS-oVEMP in the RVC group (P < 0.05), the AAR was within the normal range. However, no statistical difference was found in the AAR of GVS-oVEMP in the two groups (P > 0.05). Conclusion: The latencies of ACS-cVEMP and GVS-cVEMP in children with recurrent vertigo were significantly prolonged compared with those in healthy children, and there was no difference in elicit rates of ACS-cVEMP and GVS-cVEMP, suggesting that there might be potential impairment in the inferior vestibular nerve and the subsequent nerve conduction pathway in RVC.
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Objective:This study was to retrospectively analyze the results of vestibular-evoked myogenic potentialsï¼VEMPï¼ in unilateral Meniere's diseaseï¼MDï¼ patients. Methods:The clinical assessment results of MD patients who visited the department between January 2016 to February 2022 were reviewed. Unilateral MD patients who met the inclusion and exclusion criteria were divided into three groups according to clinical stages, namely, group 1ï¼stage â + stage â ¡ï¼, group 2ï¼stage â ¢ï¼ and group 3ï¼stage â £ï¼. The normal value data were used to investigate the incidence of abnormal P1 and N1 latencies, abnormal P1-N1 interwave latency, and abnormal interaural amplitude asymmetry ratioï¼IARï¼. Afterwards, considering all the above mentioned parameters, the VEMP result of each patient was graded into four levelsï¼grade 1 means VEMP result is normal, grade 2, 3 and 4 means the VEMP result is abnormal in different degreesï¼. The correlation between VEMP result level and pure tone averageï¼PTAï¼ of MD patients in different clinical stages was examined. Results:The prevalence of cVEMP in three groups was 84.2%, 70.0% and 33.3%, respectivelyï¼P<0.05ï¼. The prevalence of oVEMP in three groups was 63.2%, 34.0% and 16.7%, respectivelyï¼P<0.05ï¼. The incidence of abnormal P1 latency, N1 letancy and P1-N1 interwave latency of cVEMP was 21.1%, 26.3% and 24.6%, respectively. The incidence of abnormal P1 latency, N1 latency and interwave latency of oVEMP was 15.6%, 43.8% and 3.1%, respectively. The incidence of abnormal cVEMP IAR in group 1, group 2 and group 3 was 6.7%, 21.2% and 33.3%, respectivelyï¼P>0.05ï¼. The incidence of abnormal IAR of oVEMP in group 1, group 2 and group 3 was 16.7%, 23.1% and 0, respectivelyï¼P>0.05ï¼. cVEMP and oVEMP result levels were significantly correlated with PTAï¼r=0.339, P<0.01; r=0.362, P<0.01 ï¼, respectively. Conclusion:With the progression of MD, the function of saccule-vestibular inferior nerve pathway and utricle-vestibular superior nerve pathway would deteriorate in the same way as hearing.
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Enfermedad de Meniere , Potenciales Vestibulares Miogénicos Evocados , Vestíbulo del Laberinto , Humanos , Estudios Retrospectivos , Sáculo y Utrículo , Potenciales Vestibulares Miogénicos Evocados/fisiologíaRESUMEN
Objective:To investigate the effect of different rotations modes of control rod on testing results of the subjective visual vertical ï¼SVVï¼. Methods:Twenty-four normal young volunteers were selected for this study, and the control rod of SVV was rotated in clockwise, counterclockwise and any direction at the head tilt-positions of 0°, 45° left and 45° right. The differences of SVV deflection angle values at different rotation modes were analyzed. Results:â The deviation angle values of SVV obtained by rotating the control rod in clockwise, counterclockwise and any direction at the head tilt-positions of 0° were 1.56°±0.21°, 3.05°±0.24°, and 2.16°±0.22°, respectivelyï¼and the difference was statistically significant ï¼P<0.05ï¼,the deviation angle value of SVV in clockwise direction was smaller; â¡At head tilt-positions of 45° left, the SVV deviation angle values obtained by rotating the control rod in three rotation modes were 2.59°±0.53°, 4.03°±0.51°, and 3.49°±0.54°, respectively, and the difference was statistically significantï¼P<0.05ï¼,the deviation angle value in the clockwise direction was also smaller; â¢At the head tilt-positions of 45° right, the SVV deviation angle values in three modes were 4.68°±0.58°, 7.23°±0.72°, and 5.93°±0.96°, respectively, and the difference was statistically significant ï¼P<0.05ï¼,the deviation value of SVV was also smaller when rotated in the clockwise direction; â£Comparison of SVV deviation angle values in three rotation modes at the head tilt-positions of 45° left and 45° right showed that there was no statistical difference in clockwise and in any direction ï¼P>0.05ï¼, while the difference was statistically significant when rotated in the counterclockwise direction ï¼P<0.05ï¼. Conclusion:Different rotation modes of the control rod during SVV testing will affect the test results. Rotating the control rod in clockwise direction to make the SVV values more accurate is recommended.
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Percepción Visual , HumanosRESUMEN
Objective:To investigate the correlation between Mandarin acceptable noise level ï¼M-ANLï¼ and cortical auditory evoked potential ï¼CAEPï¼, and to explore the possible mechanism leading to individual differences in M-ANL values. Methods:Thirty listeners aged 22-33 years with normal hearing were selected as the study subjects, and the M-ANL test and CAEP test were performed respectively. The most comfortable level ï¼MCLï¼, maximum background noise level ï¼BNLï¼, M-ANL and CAEP values of each subject were recorded. The latency of each wave of P1, N1, P2, N2, P300 and the amplitude of P1-N1, P2-N2, P300 in CAEP were recorded for each subject. SPSS 25.0 was used for statistical analysis to explore the correlation between the MCL value, BNL value and M-ANL values and the latency of P1, N1, P2, N2, P300 and P1-N1, P2-N2, P300 amplitudes of CAEP. Results:â The MCL value and M-ANL value were positively correlated with the P2 latency of CAEP, and the correlation coefficients were 0.404 and 0.400, respectively, and the differences were statistically significant ï¼P<0.05ï¼. There was no correlation with P1, N1, N2, and P300 latencies of CAEP ï¼P>0.05ï¼. â¡The MCL value, BNL value and M-ANL value had no significant difference with the CAEP wave amplitudes of P1-N1, P2-N2, and P300 ï¼P>0.05ï¼. Conclusion:There was a certain correlation between M-ANL and CAEP in young adults with normal hearing, suggesting that the central auditory cortex might play a potential regulatory role in the background noise tolerance. Individuals with a greater background noise acceptance might have stronger central efferent mechanisms and/or less active central afferent mechanisms.
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Corteza Auditiva , Percepción del Habla , Estimulación Acústica , Potenciales Evocados Auditivos , Audición , Humanos , Ruido , Adulto JovenRESUMEN
OBJECTIVE: To explore the possible pathogenesis of recurrent vertigo of childhood (RVC) and the clinical diagnosis value of vestibular-evoked myogenic potentials (VEMPs). METHODS: The clinical data of 19 children (5.95 ± 0.38 years) diagnosed with RVC and 17 normal children (5.35 ± 0.31 years) enrolled in the control (NC) group from April 2017 to February 2021 was collected and analyzed. All subjects were tested for both cervical VEMP (cVEMP) and ocular VEMP (oVEMP). The elicit rate, thresholds, N1 latency, P1 latency, interval, amplitude, and amplitude asymmetry ratio (AAR) of VEMPs were compared and analyzed between the two groups. RESULTS: (1) The elicit rates of cVEMP and oVEMP have no significant difference between the two groups (P > 0.05). (2) The thresholds of cVEMP and oVEMP in the RVC group were higher than that in the NC group (P < 0.05). (3) The N1 latency of cVEMP in the RVC group was longer than that in the NC group (P < 0.05). The P1 latency of cVEMP and latencies of oVEMP have no significant difference between the two groups (P > 0.05). (4) The interval of cVEMP in the RVC group was longer than that in the NC group (P < 0.05), while the interval of oVEMP has no significant difference between the two groups (P > 0.05). (5) The amplitude of cVEMP in the RVC group was higher than that in the NC group (P < 0.05), while the amplitude of oVEMP was similar in the two groups (P > 0.05). (6) The AAR values of oVEMP and cVEMP were similar in the two groups (P > 0.05). CONCLUSIONS: The elicit rates of VEMPs in children with RVC did not differ from that of normal children, but the thresholds were all increased, suggesting reduced sensitivity of the otolith organ and vestibular nerve conduction pathways. The P1 latency of cVEMP was normal in children with RVC, but N1 latency and interval of cVEMP were increased, we finally reached a conclusion that there might be potential impairment in the inferior vestibular nerve and the subsequent nerve conduction pathway in RVC.
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Potenciales Vestibulares Miogénicos Evocados , Niño , Mareo , Humanos , Recurrencia Local de Neoplasia , Sáculo y Utrículo , Vértigo , Potenciales Vestibulares Miogénicos Evocados/fisiologíaRESUMEN
Objective:The aim of this study was to investigate the speech recognition in noise in patients with unilateral hearing lossï¼UHLï¼, and explore the compensation effect of behind-the-earï¼BTEï¼ hearing aid on speech recognition in patients with varied degrees of UHL. Methods:Twenty-five participants with UHL were divided into two groups according to the degree of hearing loss: one group included subjects with unilateral moderate and moderately severe hearing loss and another one included subjects with unilateral severe and profound hearing loss. Fifteen healthy subjects with normal hearing were enrolled as the control group. The speech recognition thresholds and speech recognition scores at fixed signal noise ratioï¼SNRï¼ in UHL participants with and without BTE hearing aid were tested in the sound field and compared with those in the control group. One-way ANOVA was used to examine the significance of the difference between UHL participants and control group, and paired t-test was used to analyze the compensation effect of hearing aid on speech recognition in noise in UHL participants. Results:The speech recognition thresholds were significantly higher in both UHL groupsï¼P<0.01ï¼ compared with the control group, there was no significant difference between two UHL groups. And the speech recognition scores were significantly lower when the SNR was fixedï¼P<0.01ï¼, and there were no significant differences between two UHL groups. When fitting BTE hearing aid, the speech recognition thresholds of the two groups significantly decreasedï¼P<0.01ï¼, and the speech recognition scores significantly improvedï¼P<0.01ï¼. Conclusion:Patients with above moderate UHL presented a significant decrease in performance of speech recognition in noise, and fitting BTE hearing aid on the affected ear had a positive compensation effect.
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Sordera , Audífonos , Pérdida Auditiva Unilateral , Percepción del Habla , Humanos , RuidoRESUMEN
The excellent properties of III-nitrides and their alloys have led to significant applications in optoelectronic devices. Boron, the lightest IIIA group element, makes it possible to extend the flexibility of III-nitride alloys. However, both BxAl1-xN and BxGa1-xN ternary alloys suffer from poor material quality during crystal growth, their B contents in experimental reports are no higher than 22%, and the underlying mechanism is still unclear. Herein, ab initio global calculation by particle swarm optimization combined with density functional theory is carried out to identify the ground structures of BxAl1-xN alloys with different B contents (x = 0.25, 0.5, and 0.75). Furthermore, the electronic properties and intrinsic carrier mobility are studied. For B0.25Al0.75N and B0.75Al0.25N, quasi-wurtzite and quasi-hexagonal structures are energetically favourable, respectively, indicating a wurtzite-to-hexagonal structural transition due to the three-coordinated B atoms being incorporated into the lattice. When the B content is 50%, B0.5Al0.5N shows a ten-membered ring structure with an indirect bandgap of 3.52 eV and strong anisotropy of mobility. Our results uncover the mechanism of the structural and electronic property evolution with B content and pave a route for the application of B-containing III-nitride alloys.