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Transition metal phosphides (TMPs) have been widely studied for water decomposition for their monocatalytic property for anodic or cathodic reactions. However, their bifunctional catalytic activity still remains a major challenge. Herein, hexagonal nickel-cobalt bimetallic phosphide nanoneedles with 1-3 µm length and 15-30 nm diameter supported on NF (NixCo2-xP NDs/NF) with adjusted electron structure have been successfully prepared. The overall alkaline water electrolyzer composed of the optimal anode (Ni0.67Co1.33P NDs/NF) and cathode (Ni1.01Co0.99P NDs/NF) provide 100 mA cm-2 at 1.62 V. Gibbs Free Energy for reaction paths proves that the active site in the hydrogen evolution reaction (HER) is Ni and the oxygen evolution reaction (OER) is Co in NixCo2-xP, respectively. In the HER process, Co-doping can result in an apparent accumulation of charge around Ni active sites in favor of promoting HER activity of Ni sites, and ΔGH* of 0.19 eV is achieved. In the OER process, the abundant electron transfer around Co-active sites results in the excellent ability to adsorb and desorb *O and *OOH intermediates and an effectively reduced ∆GRDS of 0.37 eV. This research explains the regulation of electronic structure change on the active sites of bimetallic materials and provides an effective way to design a stable and effective electrocatalytic decomposition of alkaline water.
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BACKGROUND: In pure tone audiometry, when the difference of the Average Air Conduction Threshold of pure tone (AACT) between bilateral ears is more than 40 dB HL masking must be performed on the poor side, However, we found that masking also make significance difference when the binaural AACT difference (AACT-d)was less than 40 dB HL in some patients. AIMS/OBJECTIVE: Assessing the significance of masking for the poor ear in pure tone audiometry in patients with different types of deafness to obtain preoperative accurate hearing. MATERIAL AND METHODS: A comparative analysis of 163 cases (163 ears) with hearing difference between two ears was conducted, who were divided into three groups: G1 Congenital Malformation of the Middle and Outer Ear (CMMOE)as conductive deafness, 63 ears, G2 sudden deafness as sensorineural deafness, 65 ears, and G3 media otitis as conductive or mixed deafness,35 ears. AACT-d before and after the poor ear masking was analyzed under the following three conditions: (1) 0.125-8 KHz each frequency, (2) 0.5-4 KHz on average, (3) the frequencies of AACT-d ≥ 40 dB HL and <40 dB HL between the two ears before masking. If the sample data did not follow a normal distribution, the Wilcoxon rank sum test was used for comparasion of AACT, and p < 0.05 was considered statistically significant. It is clinically effective for AACT-d ≥ 15 dB HL at 1 frequency or 10 dB HL ≤ AACT-d at 2 frequencies <15 dB HL before and after masking. RESULTS: Among the three groups, (1) the comparasion of AACT-d before and after the poor ear masking for each frequency of 0.125-8 KHz and 0.5-4 KHz on average with all p < 0.05, and the AACT-d of the G1 group was the largest, with an average 0.5-4KHz of 7.5 dB HL, and the first two were 14.5 dB HL and 13.8 dB HL at 0.125 KHz and 0.25 KHz, respectively. (2) AACT-d ≥ 40 dB HL and <40 dB HL between the two ears before masking were distributed at the full frequency of 0.125-8KHz, the clinically effective rates of ≥40 dB HL groups were G1 (89.3%), G2 (45.5%) and G3 (5.3%), while those of < 40 dB HL groups were G1 (69.7%), G2 (34.4%) and G3 (31.3%), respectively. CONCLUSION AND SIGNIFICANCE: For all three groups, there was statistically significant in AACT-d before and after the poor ear masking across each frequency of 0.125-8 KHz and on average 0.5-4 KHz. The distribution of AACT-d ≥ 40 dB HL and <40 dB HL between the two ears before masking was observed throughout the full frequency range of 0.125-8 KHz. AACT-d before and after the poor ear masking showed clinical effectiveness in all three groups, with the highest effective rate observed in the G1 group and the highest AACT-d at 0.125 KHz and 0.25 KHz. Therefore, regardless of whether the AACT-d between the two ears before masking is ≥40 dB HL or <40 dB HL, the full frequency masking should be employed in three groups, especially for the G1 group of CMMOE, particularly at 0.125 KHz and 0.25 KHz.
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Surdez , Perda Auditiva Neurossensorial , Humanos , Audiometria de Tons Puros , Limiar Auditivo , AudiçãoRESUMO
BACKGROUND: At present, there are not international unified standards and reports on Congenital Ear Malformation (CEM) in the world, which makes it difficult to transfer information and compare the literature. AIMS/OBJECTIVES: Through the statistical analysis of a large sample of CEM, a unified standard of all aspects of CEM is proposed and the data are provided for reference, which is convenient for the international work and literature comparison in this field. MATERIALS AND METHODS: Based on the author's 30 years of clinical and scientific research work on CEM and the relevant cases of 3231 (4714 ears) in our hospital, and combined with literature, statistical analysis was made. RESULTS: This paper summarizes the classification, definition, epidemiology, embryonic development, pathogenic factors of CEM and elaborates on the clinical manifestations, examination and sequence therapy of representative Congenital Malformation of the Middle and Outer Ear (CMMOE). We also introduce malformation of the auricle and inner ear, so as to cover the outer, middle and inner ear. At the same time, we introduce our achievements and contributions in this field. CONCLUSIONS AND SIGNIFICANCE: This study provides reference to the international unified standard and treatment principle of the CEM.
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Pavilhão Auricular , Orelha Interna , Orelha Média/anormalidades , Orelha Externa , Orelha Interna/anormalidadesRESUMO
Background: There is no report on the relationship between congenital malformation of the outer ear and hearing, which makes it possible to predict the hearing level just based on microtia grades.Aims/Objectives: To investigate the correlation between two types of congenital malformation of the outer ear [microtia and Outer Ear Canal Malformation (OECM)] and hearing, as well as the interrelationship among all three variables.Material and methods: A total of 535 cases (598 ears) of congenital malformation of the middle and outer ear (CMMOE) with hearing data, out of which 319 cases (349 ears) microtia with available images and graded by I-V, 449 cases (482 ears) OECM graded by atresia, stenosis and normal, and 87 cases (87 ears) OEC atresia graded I-IV, 301 cases (301 ears) with materials of microtia, OECM and hearing at the same time were carried out correlation analysis. The Average Air-Conduction Threshold of pure tone (AACT) at 0.5-4 KHz was calculated corresponding to the ears with different malformation grades. The differences in AACT among different malformation grades, the correlation between malformation severity and AACT, as well as the relationship among microtia, OECM and AACT were analyzed. The one-way analysis of variance (ANOVA) was employed to compare the differences in AACT, Kendall's tau-b rank correlation coefficient test was used for correlation analysis. A statistical significance level of p < 0 .05 was applied.Results: Among the 349 ears with microtia, the corresponding AACT values for grades I to V were 61.6, 63.0, 69.9, 75.4, and 75.0 (dB HL), respectively. Comparing grade III to grades II or IV, both p < 0 .05. However, p > 0 .05 between grade I and II or between grade IV and V. The correlation coefficient between microtia grades and AACT r = 0.219, p < 0.05. Among the 482 ears of OECM, the distribution was as follows: 73.6% atresia, 19.1% stenosis, and 7.3% normal, the corresponding AACT values were 64.1, 61.7, and 52.5 (dB HL), respectively. Comparing normal to stenosis or atresia, both p < 0.05, while between atresia and stenosis p > 0.05. The correlation between OECM and AACT was r = 0.104, p < 0.05. The AACT values corresponding to grades I to IV of OEC atresia in the 87 ears were 59.9, 65.1, 71.1, and 64.1 (dB HL), respectively. Comparing these grades, all p > 0.05. The correlation between the degree of atresia and AACT r = 0.23, p < 0 .05. The correlation coefficients for 301 ears microtia to OECM, microtia to AACT, OECM to AACT were r = 0.339, r = 0.163 and r = 0.128 respectively, with all p < 0 .05.Conclusion and significance: There are positive correlations among the degree of microtia, degree of OECM, and AACT values for each other, and so between the degree of OEC atresia and AACT, suggesting that as the severity of microtia or OECM increased, the AACT also tended to be higher, which make it possible to predict the hearing level and the degree of OECM based on microtia grades in clinical practice. Additionally, there are significant differences in AACT values in microtia grade III to grades II or IV, OEC normal to stenosis or atresia, while no differences in microtia grade I to II and grade IV to V, OEC stenosis to atresia, and among the grades I-IV of the OEC atresia.
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Microtia Congênita , Humanos , Constrição Patológica , Orelha/anormalidades , Audição , Meato Acústico ExternoRESUMO
Background: There is no study on the hearing features of congenital malformation of middle and outer ears (CMMOE), including classification, grades, and frequency characteristics, which play a decisive role in the selection of precise hearing solutions for patients. Aims/Objectives: To analyze the hearing features of CMMOE and provide guidance for clinical practice.Material and Methods: 298 cases (351 ears) with CMMOE were retrospectively analyzed for the features of 0.5 â¼ 4KHz pure tone hearing, including the classification, grades and frequency characteristics. Results: We observed conductive deafness in 84.3% (296/351), mixed deafness in 15.7% (55/351), and 0% (0/351) sensorineural deafness. Grades measured by average Air Conduction Thresholds (ACT) of pure tone: Mild deafness (26-40dB HL) 0.6% (2/351), moderate deafness (41-55dB HL) 10.3% (36/351), moderate to severe deafness (56-70dB HL) 46.1%(162/351), severe deafness (71-90dB HL) 39.9%(140/351), extremely severe deafness (> 90 dB HL) 3.1%(11/351). The average ACT of 296 ears conductive deafness was 67 ± 10 dB HL, of which 56-80dB HL accounted for 78.1% (274/351). In 55 ears with mixed deafness, 32 ears (32/55 = 58.2%) increased Bone Conduction Threshold (BCT) at a single frequency, and out of 32 ears, 31ears (31/55 = 56.4%) ≤40dB HL, 25(25/32 = 78.1%) ears at 2KHz. In 55 ears with mixed deafness, 87.3% (48/55) increased BCT at 2KHz, and the average BCT was 35 ± 10dB HL. Conclusions and Significance: CMMOE result mainly in conductive deafness, moderate to severe and severe deafness. In mixed deafness, the BCT increased mainly at a single frequency, 2KHz and ≤40dB HL. These data suggest that bone-conductive hearing devices are a good solution for CMMOE hearing impairment.
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Surdez , Perda Auditiva Condutiva-Neurossensorial Mista , Perda Auditiva , Humanos , Estudos Retrospectivos , Audiometria de Tons Puros , Perda Auditiva Condutiva , Condução Óssea , Orelha Externa , Limiar AuditivoRESUMO
Background: No selection criteria for the four bone conduction hearing devices yet.Aims/Objectives: To compare effectiveness of four bone conduction hearing devices in patients with bilateral Congenital Malformation of the Middle and Outer Ear (CMMOE).Material and Methods: 24 Patients (25 ears) were divided into five groups: 1) Bone Anchored Hearing Aid softband (BAHA-s), 2) BAHA implant (BAHA-i nested within group 1), 3) Vibration Sound Bridge implant (VSB-i), 4) Bone Bridge implant (BB-i), and 5) Bone Conduction Hearing Aid softband (BCHA-s). One patient implanted VSB and BB. Auditory parameters were compared: 1. Communication, 2. Average Air Conduction Thresholds (ACT) of pure tone, 3. Sentence Recognition Scores in quiet (SRS-q) and noisy (SRS-n) settings. The one-way analysis of variance (ANOVA) were employed to compare the differences in ACT and SRS-q/n among the groups, a statistical significance level of P < 0.05 was applied.Results: After hearing aid usage, all 24 patients (25 ears) reached or approached the normal in communication (i.e. from difficult to smooth), average ACT and SRS-q/SRS-n (no difference among groups, p > 0 .05). However, there was the difference in the optimal frequency of ACT and the absolute value of SRS-q/SRS-n for VSB/BAHA implants was higher than that for BB and BAHA softband.Conclusions and Significance: The precise selection of the four hearing devices mainly depends on patient's hearing level, the optimal frequency of ACT and absolute values of SRS-q/SRS-n.
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Auxiliares de Audição , Humanos , Condução Óssea , Perda Auditiva Condutiva/reabilitação , Orelha Externa , SomRESUMO
BACKGROUND: There are no reports about comprehensive comparative analysis of the effects after various hearing surgery solutions for congenital malformation of the middle and outer ear (CMMOE). AIMS/OBJECTIVES: To analyze the improvement of Average Air-Conduction Threshold (AACT) of pure tone after various hearing surgery solutions for CMMOE and provide a reference for the selection of accurate hearing solutions. MATERIALS AND METHODS: A retrospective analysis of 159 cases (170 ears) with CMMOE submitted to various ear surgery solutions, including: (1) Three situations of outer ear canal (OEC): â atresia 85 ears, â¡ stenosis 28 ears, and ⢠normal 57 ears. (2) Three commonly used hearing solutions: eardrum repair 53 ears, Porp 44 ears and Piston 32 ears implantation. (3) Three OEC situations with different hearing solutions: type I. Reconstruction of OEC (r-OEC), type II. r-OEC and/or different tympanoplasty, including â eardrum repair, â¡ release of ossicular chain, ⢠Porp implantation, and ⣠Torp implantation, type III. Piston implantation with fenestration of the inner ear. Compare AACT of postoperative short term (0.5 years) or long term (0.5-10 years) and preoperative in the speech frequency range of 0.5-4 kHz to assess efficacy. If the sample number ≥10, and not subject to normal distribution, the Kruskal-Wallis multi-sample rank sum test is used for the comparison of multiple groups and Wilcoxon's rank sum test for two groups, with P < 0.05 being statistically significant. If the sample size <10, the standard of clinical efficacy is one frequency improvement value ≥15 dB HL, or 10 dB HL ≤2 frequency improvements <15 dB HL at 0.125-8 KHz. RESULTS: Intra-group comparison of AACT: (1) three situations of OEC: atresia, stenosis and normal all had P < 0.05 postoperatively in short term, while in long term only the normal group had P < 0.05. (2) Three commonly used hearing solutions: eardrum repair, Porp and Piston implantation all had P < 0.05 in short and long terms, except for eardrum repair P >0 .05 in long term. (3) Three OEC situations with different hearing solutions: 1) Atresia of OEC: Porp and Piston implantation, r-OEC and release of ossicular chain were effective in short term and were not effective in long term, and the eardrum repair was not effective in both short and long term. 2) Stenosis of OEC: eardrum repair, Porp and Piston implantation were effective in short and long term. r-OEC P >0 .05 for short and long term, Torp implantation was not effective in long term, 3) Normal of OEC: Porp, Torp and Piston implantation were all P < 0.05 in short and long term except for Torp >0.05 in long term, and release of ossicular chain is both short and long term clinically effective. The AACT values of postoperative in long term for three groups of atresia, stenosis, normal of OEC are over 58.7 dB HL (except Porp implantation 52.5 dB HL), 51.3 dB HL (except Porp implantation 42.5 dB HL), and 37.5 dB HL (except Torp implantation are 32.6 dB HL), respectively. CONCLUSIONS AND SIGNIFICANCE: Intra-group comparison of AACT. (1) Three groups of the atresia, stenosis and normal of OEC are all effective in short term, while in long term only the normal group is effective. (2) The three most commonly used surgical solutions of eardrum repair, Porp and Piston implantation are effective in short and long terms, except for long term eardrum repair. (3) Three OEC situations with different hearing solutions: some of surgical solutions were effective in short term or long term for CMMOE, but based on the AACT values of postoperative in long term for three OEC situations, it is better to choose a hearing device for atresia of OEC, comprehensive review of surgical or hearing device for stenosis of OEC. Surgery can be considered for normal OEC.