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Objective: Intracapsular enucleation (ICE) of cervical sympathetic chain schwannoma (CSCS) is associated with technical difficulties, with diffuse hemorrhage being the main challenge in our previous attempts. This article presents our new strategy for achieving better hemostasis during ICE procedures in CSCS cases. Methods: A retrospective review of CSCS cases treated at our tertiary medical institution was undertaken between April 2018 and February 2024. Only cases with successful ICE were included. Results: A total of 8 cases were included, with 4 male and 4 female patients and an age range of 23 to 77 (average and median ages were 48.5 and 49.5 years, respectively). The presenting symptom was a neck mass for all the patients, with 4 masses on the left and 4 on the right sides. Enucleation was first undertaken for the first 3 cases (before March 2022), followed by hemostasis; this strategy was quite difficult and time-consuming. For the remaining 5 cases, a new strategy was developed to preemptively manage any potential nourishing vessel between the capsule and tumor parenchyma, which significantly decreased operation time (P = .0155) and facilitated hemorrhage control. First bite syndrome (FBS) was avoided in all cases. Postoperative Horner's syndrome (HS) was avoided in 1 patient (Case 6, new strategy) but occurred in 7 patients, taking 8 days to 1 month to recover with the new strategy (4 patients), significantly shorter (P = .0364) than before (3 patients, 1-3 months). The median duration of follow-up was 20 months. No recurrence was documented. Conclusions: ICE was achieved for CSCS cases, especially with our newly developed strategy, by preemptively and securely managing potential nourishing vessels. Operation time and duration of recovery of postoperative HS could both be shortened. Moreover, FBS could be avoided.
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High-throughput screening (HTS) is pivotal in the discovery of small molecules that bind to DNA, yet there are limited sensing mechanisms available for designing HTS assays for DNA binders. Herein, we introduce a binder-responsive toehold-mediated DNA strand displacement (BR-TMSD) technique featuring programmable reaction kinetics in response to DNA-binder interactions. When two DNA binders are used, BR-TMSD is initiated through a rapid binder displacement, followed by the DNA strand displacement. The orthogonal displacement reactions of BR-TMSD enables a high-fidelity, dual-channel HTS assay, returning 19 new DNA binders from a library of 1,170 compounds.
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Introduction: The intricate relationship between migraine and insomnia has been a subject of great interest due to its complex mechanisms. Despite extensive research, understanding the causal link between these conditions remains a challenge. Material and Methods: This study employs a bidirectional Mendelian randomization approach to investigate the causal relationship between migraine and insomnia. Risk loci for both conditions were derived from large-scale Genome-Wide Association Studies (GWAS). The primary method of Mendelian Randomization utilized in this study is the Inverse Variance Weighted (IVW) method. Results: Our findings indicate a bidirectional causal relationship between migraine and insomnia. In the discovery set, migraine had a significant effect on insomnia (OR=1.02, 95% CI=1.02 (1.01-1.03), PIVW=5.30E-04). However, this effect was not confirmed in the validation set (OR=1.03, 95% CI=1.03 (0.87-1.21), PIVW=0.77). Insomnia also had a significant effect on migraine (OR=1.02, 95% CI=1.02 (0.01-1.03), PIVW=2.67E-08), and this effect was validated in the validation set (OR=2.30, 95% CI=2.30 (1.60-3.30), PIVW=5.78E-06). Conclusion: This study provides meaningful insights into the bidirectional causality between migraine and insomnia, highlighting a complex interplay between these conditions. While our findings advance the understanding of the relationship between migraine and insomnia, they also open up new avenues for further research. The results underscore the need for considering both conditions in clinical and therapeutic strategies.
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In this paper, a wide-band, low-profile antenna is presented for a high-integration phased array system. The proposed antenna, implemented using a tightly coupled array, operates over roughly the X-K frequency band and is performant at 8 GHz-18.5 GHz. The antenna can scan to ±60 degrees in both the E- and H-planes. Compared to previous tightly coupled antennas with smaller element spacing, the antenna in this paper reaches 9.4 mm, which corresponds to 0.58 λ of high frequency, suitable for engineering application conditions in production. The antenna can be soldered to BGA T/R chips in this space. Additionally, to facilitate flexible assembly for large arrays, the antenna is manufactured modularly using four elements and its parasitic radiation is analyzed. Then, a method for repressing parasitic radiation is presented. Finally, the antenna is fabricated and measured in a microwave chamber, exhibiting an excellent pattern and scanning radiation. The measured performance agrees with the full-wave finite array simulations.
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OBJECTIVE: To construct the complementary food texture in infants and young children aged 6 to 23 months, and observe the acceptability of complementary food of different months old infants. METHODS: Based on the domestic and foreign guidelines, consensus and literatures on complementary feeding, and combined with the characteristics of children's growth and development in China. The complementary food texture index of 6-23 months old infants and young children was constructed. One province was selected in the south and north respectively, one city and one rural area was selected as the observation point in each province. The stratified random sampling principle was adopted in each observation point, 240 infants and young children were selected for the acceptability study. According to the food type, 12 common foods were selected to make the complementary food toolkit. The parents were instructed to make complementary food at home according to the corresponding month age, observe and record the acceptability of single/mixed complementary food feeding. RESULTS: The complementary food texture index of 6 months, 7-8 months, 9-11 months, 12-17 months, 18-23 months was constructed. Caregivers could make complementary food at the corresponding month age according to the established complementary food texture index. The acceptability of single complementary food for infants and young children aged 6-23 months was 98.3%, 98.7%, 99.8%, 96.9% and 97.5%, respectively. The acceptability of mixed complementary food for children aged 7-23 months was 98.3%, 99.6%, 93.8% and 97.5%, respectively. CONCLUSION: The complementary food texture index of different month age can be made at home, and the acceptability of different texture is good.
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Alimentos Infantis , Fenômenos Fisiológicos da Nutrição do Lactente , Lactente , Humanos , Masculino , Feminino , China , Preferências AlimentaresRESUMO
Objective: Pyriform fossa (PF) branchial apparatus anomalies (PFBAA) are rare congenital third or fourth branchial apparatus anomalies (TBAA or FBAA). This article summarizes our paradigm in managing this condition by combining endoscopic procedures and open neck surgery. Methods: A retrospective review was undertaken concerning PFBAA cases treated at our tertiary medical institution between July 2020 and November 2023. Data were collected from case records. Three sequential steps were implemented: (1) direct laryngoscopy to identify internal orifice (IO), with injection of methylene blue into it; (2) open neck surgery to resect all inflammatory tissues, focusing on the ligation of the sinus tract out of PF; and (3) plasma coblation of IO mucosa. Results: In total, 7 cases (4 men and 3 women) were included (28-67 years old, median age 53). Presenting symptoms were various, with 6 lesions on the left and 1 on the right side. Preoperative (PO) fiberoptic laryngoscopy identified IO in 6 patients, while PO barium esophageal study identified outflow from PF in 4 patients. A preliminary diagnosis of PFBAA could be established in all cases (2 TBAA and 5 FBAA cases). Direct laryngoscopy after general anesthesia identified IO in all cases (2 on the base of PF and 5 on the apex of PF). All the surgical procedures were successful, with uneventful recovery in all the patients. No postoperative complications were observed. All the patients resumed oral fluid intake after confirmation of no pharyngeal fistula by barium esophageal study on the seventh postoperative day. The duration of follow-up was between 6 and 40 months (with a median duration of 27 months). No recurrence was observed. Conclusion: Open neck surgery, assisted by endoscopic dyeing of sinus tracts and plasma coblation of IO mucosa, is a suitable treatment for PFBAA in adults. This paradigm is effective and safe for senior surgeons.
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Human brain demonstrates amazing readiness for speech and language learning at birth, but the auditory development preceding such readiness remains unknown. Cochlear implanted (CI) children (n = 67; mean age 2.77 year ± 1.31 SD; 28 females) with prelingual deafness provide a unique opportunity to study this stage. Using functional near-infrared spectroscopy, it was revealed that the brain of CI children was irresponsive to sounds at CI hearing onset. With increasing CI experiences up to 32 months, the brain demonstrated function, region and hemisphere specific development. Most strikingly, the left anterior temporal lobe showed an oscillatory trajectory, changing in opposite phases for speech and noise. The study provides the first longitudinal brain imaging evidence for early auditory development preceding speech acquisition.
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PURPOSE: The aim of this study was to determine the genetic cause of early onset autosomal dominant hearing loss segregating in five-generation kindred of Chinese descent and provide preimplantation genetic testing (PGT)for them. METHODS: Clinical examination, pedigree analysis and exome sequencing were carried out on the family. Minigene-based splicing analysis, in vivo RNA analysis and protein structure prediction by molecular modeling were conducted on the candidate variant. PGT for the causative variation and chromosome aneuploidis based on SNP analysis has been used for avoidance of hearing loss in this family. RESULTS: All the affected individuals presented with moderate down-sloping hearing loss and whole-exome sequencing identified a novel splice-site variant c.5383+6T>A in the tested subjects within the TECTA locus. Genotyping of all the 32 family members confirmed segregation of this variant and the hearing loss phenotype in the extended family. Functional analysis of RNA and molecular modeling indicates that c.5383+6T>A is a pathogenic splice-site variant and should be considered as genetic cause of the hearing loss. Furthermore, a successful singleton pregnancy with no variation in TECTA c.5383+6 was established and a healthy male child was born by PGT. CONCLUSION: We have identified a novel variant c.5383+6T>A in TECTA ZA-ZP inter-domain, which could be attributable to the early-onset autosomal dominant hearing loss. The implications of our study are valuable in elucidating the disrupted RNA splicing and uncovering the genetic cause of hearing loss with TECTA pathogenic variants, as well as providing reproductive approaches to healthy offspring.
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The electronic structures and elastic properties of metastable Zr3N4 phases have been investigated using the first-principles calculations with the Heyd-Scuseria-Ernzerhof (HSE06) hybrid functional, in comparison with those of the stable ZrN phase. All three metastable Zr3N4 phases (including orthorhombic, spinel and Th3P4-type phases) are found to be semiconducting with bandgaps of 1.72-1.94 eV. In particular, the computationally indirect bandgap of 1.72 eV of orthorhombic Zr3N4 is consistent with the experimental value of 1.8 eV. The detailed analyses of the electronic structures reveal that the change of electrical conductivity from metallic ZrN to semiconducting Zr3N4 is mainly due to the electron transfer from Zr to N atoms, which weakens the Zr-Zr interactions and reduces the proportion of metallic bonding. In addition, the elastic properties of Zr3N4 and ZrN phases have been calculated. The theoretical hardness values of ZrN and orthorhombic Zr3N4 are 18.06 and 6.98 GPa, respectively, agreeing well with the experimental values of 19.26 and 7.90 GPa. This work may further promote the understanding of the promising Zr-N material system.
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PURPOSE: To compare the correlation between different grading methods of vestibular endolymphatic hydrops (EH) and the severity of hearing loss in Ménière's disease (MD), and evaluate the diagnostic value of these methods in diagnosing MD. METHODS: This retrospective study included 30 patients diagnosed with MD from June 2021 to August 2023. All patients underwent inner ear MR gadolinium-enhanced imaging using three-dimensional (3D)-real inversion recovery sequences and pure-tone audiometry. The EH levels were independently evaluated according to the classification methods outlined by Nakashima et al. (Acta Otolaryngol Suppl 5-8, 2009. https://doi.org/10.1080/00016480902729827 ) (M1), Fang et al. (J Laryngol Otol 126:454-459, 2012. https://doi.org/10.1017/S0022215112000060 ) (M2), Barath et al. (Am J Neuroradiol 35:1387-1392, 2014. https://doi.org/10.3174/ajnr.A3856 ), (M3), Liu et al. (Front Surg 9:874971, 2022. https://doi.org/10.3389/fsurg.2022.874971 ), (M4), and Bernaerts et al. (Neuroradiology 61:421-429, 2019. https://doi.org/10.1007/s00234-019-02155-7 ) (M5), with a subsequent comparison of interobserver agreement. After achieving a consensus, an analysis was performed to explore the correlations between vestibular EH grading using different methods, the average hearing thresholds at low-mid, high-, and full frequencies and clinical stages. The diagnostic capabilities of these methods for MD were then compared. RESULTS: The interobserver consistency of M2-M5 was superior to that of M1. The EH grading based on M4 showed a significant correlation with the average hearing thresholds at low-mid, high-, and full frequencies and clinical stages. M1, M2, M3, and M5 correlated with some parameters. A receiver operating characteristic curve analysis indicated that M5 significantly outperformed M1, M2, M3, and M4 in terms of diagnostic efficiency for MD. CONCLUSION: M4 showed the strongest correlation with the degree of hearing loss in patients with MD, whereas M5 showed the highest diagnostic performance.
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OBJECTIVE: To investigate the relationship between vestibular aqueduct (VA) morphology and Meniere's disease (MD) using ultrahigh-resolution computed tomography (U-HRCT). METHODS: Retrospective data were collected from 34 patients (40 ears) diagnosed with MD in our hospital who underwent temporal bone U-HRCT with isotropic 0.05-mm resolution, magnetic resonance with gadolinium-enhanced, and pure-tone audiometry; 34 age- and sex-matched controls (68 ears) who underwent U-HRCT were also included. VA patency was qualitatively classified as locally not shown (grade 1), locally faintly shown (grade 2), or clearly shown throughout (grade 3). The width of the outer orifice and VA length and angle were quantitatively measured. Differences in VA morphology between the MD and control groups were analyzed. The correlations between VA morphology and the degrees of hearing loss and endolymphatic hydrops (EH) were also analyzed. RESULTS: VA was classified as grades 1-3 in 11, 17, and 12 ears in the MD group and 5, 26, and 37 ears in the control group, respectively. The patency differed significantly between the groups (p < 0.01). The width of the outer orifice and length of VA were significantly smaller in the MD group than those in the control group (p < 0.05). Both VA patency and length were correlated with the degree of EH in the cochlea and the vestibule (p < 0.05). No difference was found between VA morphology and the degree of hearing loss (p > 0.05). CONCLUSION: The morphological characteristics of VA were found to be associated with the occurrence of MD and the degree of EH. LEVEL OF EVIDENCE: 4 Laryngoscope, 134:3349-3354, 2024.
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Audiometria de Tons Puros , Imageamento por Ressonância Magnética , Doença de Meniere , Tomografia Computadorizada por Raios X , Aqueduto Vestibular , Humanos , Doença de Meniere/fisiopatologia , Doença de Meniere/diagnóstico por imagem , Doença de Meniere/patologia , Feminino , Masculino , Aqueduto Vestibular/diagnóstico por imagem , Aqueduto Vestibular/anormalidades , Aqueduto Vestibular/patologia , Estudos Retrospectivos , Pessoa de Meia-Idade , Adulto , Idoso , Estudos de Casos e Controles , Hidropisia Endolinfática/diagnóstico por imagem , Hidropisia Endolinfática/fisiopatologia , Hidropisia Endolinfática/patologia , Adulto Jovem , Osso Temporal/diagnóstico por imagem , Osso Temporal/patologiaRESUMO
Objectives: Several reports have underlined the benefits of speechreading (visual-only speech recognition) on speech recognition in individuals with hearing loss after cochlear implantation (CI). However, the factors that would affect the ability of speechreading are unclear. The aim of the present study is to assess the factors that affect speechreading abilities in CI users. Methods: A total of 104 participants were enrolled in this retrospective study. They viewed silent videos of sentences being spoken by a model and were tasked with repeating what they thought had been said. They were tested under audio-only and visual-only conditions. Factors (such as the age, the age of CI; <3 years old vs 3-8 years old; male vs female, etc) believed to affect speechreading abilities were analyzed. Results: The age range of the participants is 8 to 34 years. CI users showed significantly different speechreading abilities among themselves. The authors found that age and hearing loss at 3 to 8 years of age were positively related to superior speechreading recognition scores. Conclusions: CI users followed a more complex method of perceptual compensation. Those who have suffered hearing loss between 3 and 8 years of age are more sensitive to developing an advantage in speech recognition by using speechreading. Older age positively affects speechreading abilities; thus, the more experience CI has, the greater speechreading ability they may exhibit.
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Objective: This study explored prophylactic central compartment lymph node dissection (pCCLND) for patients with cN0 papillary thyroid carcinoma (PTC) and the effect of carbon nanoparticles (CNP) on surgical outcomes. Methods: This retrospective study reviewed PTC cases treated at our tertiary medical institution between January 2019 and December 2022. Only patients with indications for total thyroidectomy and cN0 disease were included. CNP has been associated with a higher number of harvested lymph nodes and a lower rate of accidental parathyroid gland (PTG) removal. Patients who used CNP in this study were classified as group 1, while those who denied its use were classified as group 2. Results: In total, 116 cases were included, with 80 patients in group 1 and 36 in group 2. Most patients were in stage T1, with 68 (85.0 %) patients in group 1 and 31 (86.1 %) in group 2. Postoperative hoarseness occurred in 3 (3.8 %) patients in group 1 and 1 (2.8 %) in group 2, which recovered within two months. In group 2, 250 nodes were harvested, 72 (28.8 %) of which were metastatic; in group 1, 889 nodes were harvested, 316 (35.5 %) of which were metastatic; the difference regarding the rates of metastatic lymph nodes between the 2 groups was statistically significant (P = 0.047). Differences in postoperative blood calcium and parathyroid hormone levels between the two groups were statistically significant (P = 0.035 and P = 0.034, respectively). There were symptoms of hypocalcemia in 6 (16.7 %) patients in group 2 but in only 2 (2.5 %) in group 1, all of which recovered within three months; the difference was statistically significant (p = 0.017). Conclusion: pCCLND is worth undertaking for cN0 PTC. CNP is beneficial for achieving more thorough dissection and reducing temporary hypoparathyroidism.
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OBJECTIVES: Older adults often complain of difficulty in communicating in noisy environments. Contextual information is considered an important cue for identifying everyday speech. To date, it has not been clear exactly how context use (CU) and reliance on context in older adults are affected by hearing status and cognitive function. The present study examined the effects of semantic context on the performance of speech recognition, recall, perceived listening effort (LE), and noise tolerance, and further explored the impacts of hearing loss and working memory capacity on CU and reliance on context among older adults. DESIGN: Fifty older adults with normal hearing and 56 older adults with mild-to-moderate hearing loss between the ages of 60 and 95 years participated in this study. A median split of the backward digit span further classified the participants into high working memory (HWM) and low working memory (LWM) capacity groups. Each participant performed high- and low-context Repeat and Recall tests, including a sentence repeat and delayed recall task, subjective assessments of LE, and tolerable time under seven signal to noise ratios (SNRs). CU was calculated as the difference between high- and low-context sentences for each outcome measure. The proportion of context use (PCU) in high-context performance was taken as the reliance on context to explain the degree to which participants relied on context when they repeated and recalled high-context sentences. RESULTS: Semantic context helps improve the performance of speech recognition and delayed recall, reduces perceived LE, and prolongs noise tolerance in older adults with and without hearing loss. In addition, the adverse effects of hearing loss on the performance of repeat tasks were more pronounced in low context than in high context, whereas the effects on recall tasks and noise tolerance time were more significant in high context than in low context. Compared with other tasks, the CU and PCU in repeat tasks were more affected by listening status and working memory capacity. In the repeat phase, hearing loss increased older adults' reliance on the context of a relatively challenging listening environment, as shown by the fact that when the SNR was 0 and -5 dB, the PCU (repeat) of the hearing loss group was significantly greater than that of the normal-hearing group, whereas there was no significant difference between the two hearing groups under the remaining SNRs. In addition, older adults with LWM had significantly greater CU and PCU in repeat tasks than those with HWM, especially at SNRs with moderate task demands. CONCLUSIONS: Taken together, semantic context not only improved speech perception intelligibility but also released cognitive resources for memory encoding in older adults. Mild-to-moderate hearing loss and LWM capacity in older adults significantly increased the use and reliance on semantic context, which was also modulated by the level of SNR.
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Surdez , Perda Auditiva , Percepção da Fala , Humanos , Idoso , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Memória de Curto Prazo , AudiçãoRESUMO
Recently, therapeutic cancer vaccines have emerged as promising candidates for cancer immunotherapy. Nevertheless, their efficacies are frequently impeded by challenges including inadequate antigen encapsulation, insufficient immune activation, and immunosuppressive tumor microenvironment. Herein, we report a three-in-one hydrogel assembled by nucleic acids (NAs) that can serve as a vaccine to in situ trigger strong immune response against cancer. Through site-specifically grafting the chemodrug, 7-ethyl-10-hydroxycamptothecin (also known as SN38), onto three component phosphorothioate (PS) DNA strands, a Y-shaped motif (Y-motif) with sticky ends is self-assembled, at one terminus of which an unmethylated cytosine-phosphate-guanine (CpG) segment is introduced as an immune agonist. Thereafter, programmed cell death ligand-1 (PD-L1) siRNA that performs as immune checkpoint inhibitor is designed as a crosslinker to assemble with the CpG- and SN38-containing Y-motif, resulting in the formation of final NA hydrogel vaccine. With three functional agents inside, the hydrogel can remarkably induce the immunogenic cell death to enhance the antigen presentation, promoting the dendritic cell maturation and effector T lymphocyte infiltration, as well as relieving the immunosuppressive tumor environment. When inoculated twice at tumor sites, the vaccine demonstrates a substantial antitumor effect in melanoma mouse model, proving its potential as a general platform for synergistic cancer immunotherapy.
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Melanoma , Ácidos Nucleicos , Vacinas , Animais , Camundongos , Hidrogéis/metabolismo , Ácidos Nucleicos/metabolismo , Células Dendríticas/metabolismo , Imunoterapia , Vacinação , Microambiente Tumoral , Linhagem Celular Tumoral , Antígeno B7-H1/metabolismoRESUMO
BACKGROUND: Electrophysiological tests are often used to evaluate hearing loss in infants and young children with conductive hearing loss, no matter to quantify or characterize. However, there are advantages and disadvantages associated with the various electrophysiological tests that are currently available. Therefore, there is no gold standard test. This study aimed to compare the value of narrow-band (NB) CE-Chirp-induced auditory steady-state response (ASSR) and auditory brainstem response (ABR) for assessing hearing thresholds in children with conductive hearing loss. We hope to identify an effective electrophysiological testing method to evaluate conductive hearing loss and provide a reference for clinical hearing assessment of infants with conductive hearing loss. SUBJECTS: and Methods: We selected 27 children (41 ears) aged 3-6 years with otitis media with effusion (OME). Within 1 day, they underwent behavioral audiometry and NB CE-Chirp-induced ASSR and ABR tests in sequence. Pearson's correlation analysis was performed to compare behavioral audiometry thresholds and ASSR and ABR response thresholds at 500, 1000, 2000, and 4000 Hz. RESULTS: The behavioral audiometry thresholds of all children were strongly correlated with the response thresholds of the two electrophysiological tests, with correlation coefficients of 0.659, 0.605, 0.723, and 0.857 for ASSR, and 0.587, 0.684, 0.753, and 0.802 for ABR. The proportion of children with a difference of ≤10 dB between ASSR and behavioral audiometry thresholds or between ABR and behavioral audiometry thresholds was not high, especially in the low frequencies. ABR results were superior to ASSR results in terms of predicting actual hearing levels. At 0.5, 1, 2, and 4 kHz, the average differences between the behavioral hearing thresholds and ASSR thresholds in the 41 ears were 5.6, 5.7, 2, and 5.6 dB, respectively. The average differences between behavioral hearing thresholds and ABR thresholds was -5.6, -1.4, -6.8, and 3.2 dB, respectively. The hearing loss configuration of the ASSR exhibited a peaked pattern, similar to behavioral audiometry, whereas the ABR exhibited an ascending pattern. The time to perform the single-ear ASSR test was 5.9 min, whereas the ABR test took 17.0 min. CONCLUSION: ASSR and ABR induced by the NB CE-Chirp correlated well with behavioral audiometry in children with conductive hearing loss. The NB CE-Chirp ASSR has advantages in terms of testing time and hearing configuration evaluation, whereas ABR has better reliability than ASSR. However, the stability of ASSR and ABR induced by the NB CE-Chirp is poor, and the thresholds obtained cannot replace behavioral audiometry in evaluating the true hearing of children with conductive hearing loss. However, ASSR and ABR can be used as auxiliary tests for cross-validation.
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Potenciais Evocados Auditivos do Tronco Encefálico , Perda Auditiva , Lactente , Criança , Humanos , Pré-Escolar , Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Perda Auditiva Condutiva/diagnóstico , Perda Auditiva Condutiva/etiologia , Reprodutibilidade dos Testes , Estimulação Acústica/métodos , Limiar Auditivo/fisiologia , AudiçãoRESUMO
Although underwater wireless optical communication (UWOC) has the advantages of high speed, low latency, and high confidentiality, the transmission of light in water will be affected by the absorption and scattering of particles, which will lead to the aggravation of channel path loss as well as channel pulse spreading, finally causing false codes. Therefore, how to analyze the channel impulse response (CIR) effectively is a key task in channel modeling. In this paper, we consider a two-way underwater vertical line-of-sight (LOS) communication system model, based on the inherent optical property (IOP) model of chlorophyll, using the Kopelevich phase function containing water depth information, the CIR curves under different water types and transceiver configurations are plotted using the Monte-Carlo Simulation (MCS). The obtained simulation results are fitted with the double gamma function (DGF) model and the Gaussian model, respectively. The Gaussian model exhibits better properties than the DGF model in each water condition. Based on the closed-form expression of the CIR obtained from the Gaussian model, we solve for the bit error rate (BER) and 3-dB bandwidth of the system under different settings. The conclusions obtained can be used for the design and optimization of underwater vertical channels.
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To reduce the cost of Si-Al aerogels preparation, circulating fluidized bed fly ash (CFA) was developed to be as the alternative to synthetic precursors. High energy consumption of alkali-melting and secondary wastes production were the major challenges. Here, a technique characterized by effective energy consumption and non-secondary waste was developed to convert CFA into Si-Al aerogel. The process consists two stages, preparation of Si-Al sol by sintering of CFA and Na2CO3 followed by sulfuric acid leaching, and synthesis of Si-Al aerogel by so-gel with trimethyl chlorosilane modification and ambient pressure drying. The optimization results of proportion and sintering temperature showed that the optimal temperature of sintering of Na2CO3 and CFA with the mass ratio of 0.7 was 750 °C, 100 °C lower than that of most other waste aluminosilicate materials. CaSO4·0.5H2O which meet building gypsum requirement was obtained by specifying the drying temperature of acid-leached residue at 126 °C for 2 h. The modification procedure was explored to obtain Si-Al aerogel with a large specific surface area of 857 m2/g and hydrophobic angle of 139.3°. Thermal and mechanical properties tests indicated that the Si-Al aerogels and gypsum produced from CFA exhibited promising thermal insulation and the potential application in construction.
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Cinza de Carvão , Silício , Cinza de Carvão/química , Sulfato de Cálcio , Alumínio , ResíduosRESUMO
PURPOSE: To compare the diagnostic sensitivity of ultra-high-resolution computed tomography (U-HRCT) and HRCT in isolated fenestral otosclerosis (IFO). METHODS: A retrospective analysis was conducted on 85 patients (85 ears) diagnosed with IFO between October 2020 and November 2022. U-HRCT (0.1 mm thickness) was performed for 20 ears, HRCT (0.67 mm thickness) for 45 ears, and both for 20 ears. The images were evaluated by general radiologists and neuroradiologists who were blinded to the diagnosis and surgical information. The diagnostic sensitivity of U-HRCT and HRCT for detecting IFO was compared between the two groups. RESULTS: Excellent inter-observer agreement existed between the two neuroradiologists (Cohen's κ coefficient 0.806, 95% CI 0.692-0.920), with good agreement between the general radiologists (Cohen's κ coefficient 0.680, 95% CI 0.417-0.943). U-HRCT had a sensitivity of 100% (40/40 ears) for neuroradiologists and 87.5% (35/40 ears) for general radiologists, significantly higher than HRCT (89.2% [58/65 ears] for neuroradiologists; 41.5% [27/65 ears] for general radiologists) (p = 0.042, p' < 0.000). General radiologists' sensitivity with HRCT was significantly lower compared to neuroradiologists (p < 0.000), but no significant difference was observed when general radiologists switched to U-HRCT (p = 0.152). Among the 20 ears that underwent both examinations, U-HRCT detected lesions smaller than 1 mm in 5 ears, whereas HRCT's sensitivity for neuroradiologists was 40% (2/5 ears), significantly lower than for lesions larger than 1 mm (93.3%, 14/15 ears, p = 0.032). CONCLUSION: U-HRCT exhibits higher sensitivity than HRCT in diagnosing IFO, suggesting its potential as a screening tool for suspected otosclerosis patients. CRITICAL RELEVANCE STATEMENT: Ultra-high-resolution computed tomography has the potential to become a screening tool in patients with suspected otosclerosis and to bridge the diagnostic accuracy gap between general radiologists and neuroradiologists. KEY POINTS: ⢠U-HRCT exhibits higher sensitivity than HRCT in the diagnosis of IFO. ⢠U-HRCT has a significant advantage in the detection of less than 1 mm IFO. ⢠U-HRCT has the potential to be used for screening of patients with suspected otosclerosis.
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Introduction: Auditory change detection is a pre-attentive cortical auditory processing ability. Many neurological and psychological disorders can lead to defects in this process. Some studies have shown that phase synchronization may be related to auditory discrimination. However, the specific contributions of phase synchronization at different frequencies remain unclear. Methods: We analyzed the electroencephalogram (EEG) data of 29 healthy adults using an oddball paradigm consisting of a standard stimulus and five deviant stimuli with varying frequency modulation patterns, including midpoint frequency transitions and linear frequency modulation. We then compared the peak amplitude and latency of inter-trial phase coherence (ITC) at the theta(θ), alpha(α), and beta(ß) frequencies, as well as the N1 component, and their relationships with stimulus changes. At the same time, the characteristics of inter-trial phase coherence in response to the pure tone stimulation and chirp sound with a fine time-frequency structure were also assessed. Result: When the stimulus frequency did not change relative to the standard stimulus, the peak latency of phase coherence at ß and α frequencies was consistent with that of the N1 component. The inter-trial phase coherence at ß frequency (ß-ITC)served as a faster indicator for detecting frequency transition when the stimulus frequency was changed relative to the standard stimulus. ß-ITC demonstrates temporal stability when detecting pure sinusoidal tones and their frequency changes, and is less susceptible to interference from other neural activities. The phase coherence at θ frequency could integrate the frequency and temporal characteristics of deviant into a single representation, which can be compared with the memory trace formed by the standard stimulus, thus effectively identifying auditory changes. Pure sinusoidal tone stimulation could induce higher inter-trial phase coherence in a smaller time window, but chirp sounds with a fine time-frequency structure required longer latencies to achieve phase coherence. Conclusion: Phase coherence at theta, alpha, and beta frequencies are all involved in auditory change detection, but play different roles in this automatic process. Complex time-frequency modulated stimuli require longer processing time for effective change detection.