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The high-performance and sustainable electrocatalysts toward oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) are essential for rechargeable Zn-air batteries (ZABs). In this paper, a natural all-components bamboo is provided as the carbon source, and melamine and cobalt chloride are provided as the nitrogen and cobalt sources, respectively. As a result, the unique helical carbon nanotubes (HCNTs) encapsulated cobalt nanoparticles are prepared, which are acted as ORR/OER electrocatalysts to improve ZABs performance. The resultant HCNTs contribute to high ORR/OER activities via exposing more CoâN sites, providing excellent electron conductivity, and facilitating mass transfer of the reactant. The HCNTs assembled rechargeable liquid ZABs showed a maximum output power density of 226 mW cm-2 and a low voltage gap of 0.85 V for 330 h cycles. The flexible all-solid-state ZABs achieved the maximum power density with 59.4 mW cm-2 and charge-discharge cycles over 25 h. The density functional theory (DFT) calculations reveal that the increase of CoâN at HCNTs effectively regulates the electronic structure of Co, optimizing the binding affinity of oxygen intermediates and resulting in the low ORR/OER overpotentials. This work paves the way for transforming renewable bamboo biomass into versatile electrocatalysts, which boosts the development of next-generation energy storage and conversion devices.
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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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Electrochemical reduction of nitrogen is considered a promising route for achieving green and sustainable ammonia synthesis under ambient conditions. A transition metal atom loaded on N-doped graphene is commonly used in the nitrogen reduction reaction (NRR), but the effect of the graphene's coordination environment on electron transfer has rarely been studied. Herein, the NRR performance of Fe1/2/3 clusters, anchored on single-vacancy and N-doped graphene, is investigated systematically via density functional theory (DFT). The calculation results show that the Fe2 cluster supported by two N atom-modified single-vacancy graphene displays the highest catalytic performance of NRR with the lowest energy barrier of 0.62 eV among the 12 candidates, and exhibits efficient selectivity. It has superior performance because of the highly asymmetrical distribution of electrons on graphene, the large positive charge of the Fe2, and the strong adsorption of *NNH. This study provides a new strategy to improve the NRR performance by regulating the Fe1/2/3 clusters coordination environment.
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BACKGROUND: The auditory complex of the chick, like that of humans, is made of intimate and highly ordered connections between the inner ear, the middle ear, and the outer ear. Unlike mammals, the middle ear of chick has only one ossicle, known as the columella. The independent lineages of the two suggest that some mechanism must exist that ensures the connectivity between the inner ear and the columella; however, the basis of integration is not known. RESULTS: Using quail-chick chimeras, we demonstrate that columella development depends on signaling interactions. Specifically, both pharyngeal endoderm and cranial paraxial mesoderm can alter the morphology of the columella. Only a discrete region of pharyngeal endoderm exerts this patterning activity, and this region is specified by the overlying paraxial mesoderm. CONCLUSIONS: Paraxial mesoderm is also used in the induction of the inner ear, thus we propose that this overlapping source of signalling cues in both middle and inner ear development may underlie the integration of these structures.
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Ossículos da Orelha/embriologia , Orelha Interna/embriologia , Indução Embrionária/fisiologia , Endoderma/fisiologia , Mesoderma/fisiologia , Morfogênese/fisiologia , Transdução de Sinais/fisiologia , Azul Alciano , Animais , Embrião de Galinha , Quimera/embriologia , Imuno-Histoquímica , CodornizRESUMO
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: The preoperative evaluation of Congenital Malformation of the Middle and Outer Ear (CMMOE) is very important. Jahrsdoerfer score commonly used at present, based on CT scanning images of the temporal bone, is often unable to accurately evaluate deformity and hearing level.Aims/Objectives: To investigate and promote a straightforward and easily accessible assessment method, pure tone audiometry, for the evaluation of CMMOE.Material and Methods: A total of 223 cases (244 ears) CMMOE with hearing data were retrospectively analyzed. Among them, 180 cases (197 ears) underwent exploratory tympanoplasty with clear conditions: ossicle numbers in 136 cases (147 ears) and morphology in 128 cases (138 ears) and vestibular window development in 137 cases (146 ears), and CT scans of temporal bone in 113 cases (120 ears). 1). The correlation was analyzed between ossicle numbers, ossicle morphology, Jahrsdoerfer score groups and their corresponding Average Air-Conduction Threshold of pure tone (AACT) at 0.5-4 KHz. 2) The AACT difference is compared among the above groups respectively and between the developed and undeveloped groups of vestibular window at 0.5-4 KHz and each frequency of 0.125-8 KHz. Spearman method was used for correlation analysis (calculating coefficient r and p values). For the data followed a normal distribution, a one-way analysis of variance (ANOVA) and t-test were employed, otherwise, Kruskal Wallis multiple local rank coincidence test and Wilcoxon rank sum test were used. p <0 .05 was considered statistically significant.Results: 1) The correlation coefficients between the groups of ossicle number scores, ossicle morphology scores, Jahrsdoerfer scores and their corresponding AACT are r = -0.187 (p <0 .05), r = -0.073 (p >0 .05) and r = -0.079 (p > 0.05), respectively. 2) Comparison of AACT difference based on ossicle number or morphological scores and Jahrsdoerfer scores with p > 0.05 among all groups, respectively. The AACT difference between the developed and undeveloped vestibular window groups is 5.5 (63.5/69.0) dB HL(p < .05) at 0.5-4KHz, out of 0.125-8 KHz frequency 1, 2, 4 KHz were 5.7 (65.0/70.7) dB HL, 8.4 (60.7/69.1) dB HL and 2 (61.5/63.5) dB HL, respectively, all p < 0.05, the other frequencies with all p > 0.05.Conclusions and Significance: 1) Ossicle number was correlated with AACT, but not for ossicle morphology and Jahrsdoerfer scores. 2) There was no significant difference in AACT corresponding to ossicle number or morphology scores and Jahrsdoerfer scores groups, but the patients with undeveloped vestibular window had poorer hearing than those with developed ones. Therefore, the AACT can evaluate the development of ossicle and vestibular window, and more directly reflect the hearing level than Jahrsdoerfer score. Pure tone audiometry is simple, widely used, and easily accessible, which making it a new assessment method of CMMOE.
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Orelha Média , Audição , Humanos , Audiometria de Tons Puros/métodos , Estudos Retrospectivos , Orelha Média/diagnóstico por imagem , Orelha Externa , Limiar AuditivoRESUMO
BACKGROUND: There is no report about the definition, classification and clinical epidemiological study of congenital ear malformation (CEM).Aims/Objectives: To investigate the definition, clinical classification and distribution of a large number of CEM cases, along with the clinical and epidemiological characteristics associated with congenital malformation of the middle and outer ear (CMMOE). MATERIAL AND METHODS: A total of 3231 cases (4714 ears) with CEM and related malformations were retrospectively analyzed, including 2,658 cases (4,064 ears) CEM and 573 cases (650 ears) preauricular fistulas and accessory ears, specifically related malformations to CEM. RESULTS: Among the 2,658 cases (4,064 ears) CEM, 64.9% cases were male and 35.1% were female. 52.9% cases with bilateral, 29.1% with right and 18.0% with left CEM. A subgroup of 1,050 cases (1,331 ears) was identified as CMMOE out of 1,090 cases (1,379 ears) microtia. In the CMMOE subgroup, 74.0% cases were male, 46.3% on the right side, 26.8% showed bilateral involvement. Out of the CMMOE with available images, there were 947 cases (1,105 ears). Additionally, related malformations including preauricular fistulas and accessory ears, were solely occured in 573 cases (650 ears), except for their occurrence simultaneously with CEM. The classification and distribution of CEM are as follows:1. 2658 cases of CEM (1) 69.9% of them were confined to the ear, including: â the outer ear 2.6%, the middle ear 17.0% and the inner ear 32.4%, â¡ two parts simultaneous malformations of the outer ear, the middle ear and the inner ear 17.2%, ⢠three parts simultaneous malformations of the outer ear, the middle ear and the inner ear 0.6%, (2) Multiple malformations including in CEM 29.1%; (3) syndromes related to CEM 1.0%.2. 1050 cases of CMMOE (1) 36.3% of them were confined to the middle and outer ears; (2) Multiple malformations associated with CMMOE 61.4%, including hemifacial microsomia 50.5%, accessory ears 9.8%, preauricular fistulas 9.2%, heart malformation 7.1%, and kidney malformation 2.0%; and (3) syndromes related to CMMOE 2.3%, (4) Complications of the ear 16.9%, mainly including otitis media 7.9%, outer ear canal cholesteatoma 6.3%, retroauricular abscess 1.1%, and nasal and pharyngeal complications 18.6%. The proportions of microcia grades I-â ¤ based on the images of 1105 ears CMMOE were 5.2%, 10.5%, 74.1%, 6.9%, and 3.3%, respectively. Among the 1331 ears CMMOE, the incidence rates of outer ear canal atresia, stenosis, normal, and ossicles malformation were 86.5%, 9.9%, 3.6%, and 98.3%, respectively.Conclusion and Significance: Approximately 69.9% of CEM cases were confined to the ear itself, with the highest proportion being inner ear malformation alone. Multiple malformations were predominantly associated with CMMOE. Syndromes related to CEM were relatively rare. Among cases of microtia, 96.3% were classified as CMMOE. These cases were predominantly observed in males, right ear and exhibited characteristics such as grade III microtia, atresia of the outer ear canal, ossicles malformation, and multiple malformations. The multiple malformations frequently included hemifacial microsomia, accessory ear, preauricular fistula, as well as heart and kidney deformities. CMMOE often coexisted with ear infections, cholesteatoma, and complications in the nasal and pharyngeal regions.
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Colesteatoma , Microtia Congênita , Anormalidades Craniofaciais , Fístula , Síndrome de Goldenhar , Masculino , Feminino , Humanos , Microtia Congênita/epidemiologia , Estudos Retrospectivos , Orelha Média/anormalidades , Meato Acústico ExternoRESUMO
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: 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.
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Orelha Interna , Prótese Ossicular , Humanos , Estudos Retrospectivos , Constrição Patológica , Timpanoplastia , Resultado do Tratamento , Meato Acústico Externo , AudiçãoRESUMO
Background: The incidence of re-stenosis or re-atresia after reconstruction of the Outer Ear Canal (OEC) in patients with Congenital Malformation of the Middle and Outer Ear (CMMOE) is very high (up to 48%), and it has been a difficult problem for otologists not being able to solve.Aims/Objectives: To explore new strategies and methods to improve re-stenosis or re-atresia after reconstruction of the OEC in patients with CMMOE.Material and Methods: According to the characteristics of reconstructed OEC (r-OEC) re-stenosis or re-atresia summarized by us, a number of new prevention strategies and methods have been proposed and related patent products have been designed, including the improvement of covering epithelium types and skin grafting methods (7 types), simulated drum ring function to prevent the formation of negative pressure in the cavity, and strengthen postoperative support to reduce skin shrinkage and bone hyperplasia. The postoperative effects of different ages and preoperative OEC malformations are statistically analyzed.Results: The incidence of re-stenosis/re-atresia is 14.3% (5/35) in the thin sectional skin of the temporal scalp overlap splicing skin grafting, which was significantly better than 45.5% (15/33) in the whole piece mosaic splicing and barrel skin grafting from the inner thin sectional thigh skin and overlay splicing other methods, including the inner thigh thin sectional skin, chest medium thick skin and subcutaneous pedicle + chest medium thick skin (p<0.05). The patent artificial drum ring and the model stent of the OEC have obvious effects. The mean operation age of postoperative atresia, stenosis, and good groups are 9.3, 13.1, and 12.5 years old, respectively. The proportion of preoperative atresia is 91.3%, 85.7%, and 57.7%, respectively. The total incidence of re-atresia and re-stenosis of r-OEC for two groups of atresia and stenosis of OEC before surgery is 40.5% (49/121) and 13.3% (8/60), respectively.Conclusions and Significance: The best result is found in overlapping the splicing thin sectional skin of the temporal scalp, combined with artificial drum ring implantation, effective support of postoperative model stent of OEC and post-pubertal surgery selection are new and effective strategies and methods to prevent re-stenosis or re-atresia of r-OEC. Atresia or stenosis of the OEC before the operation is the influence factor of the postoperative effect.
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Meato Acústico Externo , Orelha , Humanos , Meato Acústico Externo/cirurgia , Meato Acústico Externo/anormalidades , Constrição Patológica , Orelha/anormalidades , Retalhos Cirúrgicos , Stents , Estudos RetrospectivosRESUMO
BACKGROUND: It is the challenging clinical issue of combining debridement of infected lesions and retaining the blood skin flap for auricle reconstruction in patients of Congenital Malformation of the Middle and Outer Ear with Infection (CMMOEI). AIMS/OBJECTIVES: To innovate and introduce an surgery incision to solve the challenging clinical issue of a combined debridement of infection yet retaining a well vascularized skin flap for auricle reconstruction in patients with CMMOEI. MATERIAL AND METHODS: A combined innovated incision of ear sulcus and prefabricated earlobe was used for 23 cases (23 ears) with CMMOEI, The success in the management of the encountered infections, and the short and moderate-term outcome of the innovated incision to preserve a well-vascularized skin flap for subsequent auricle reconstruction were reviewed. The 23 cases include 10 males and 13 females, aged 4-14 years (mean 8.4 years), 7 left ears and 16 right ears. 14 ears stenosis and 9 ears atresia of the outer ear canals. RESULTS: In all 23 cases, the infections were successfully cleared without recurrence or complication with 2-year follow-up. The local skin flap and its blood supply were well preserved for subsequent auricle reconstruction. CONCLUSIONS AND SIGNIFICANCE: The new incision can facilitate clearance of infection in CMOMEI patients, and preserve the retroauricular tissues for subsequent harvesting of a well-vascularized skin flap for subsequent auricle reconstruction.
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Pavilhão Auricular , Otite Externa , Otite Média , Procedimentos de Cirurgia Plástica , Masculino , Feminino , Humanos , Retalhos Cirúrgicos , Pavilhão Auricular/cirurgia , Pavilhão Auricular/anormalidades , Otite Média/cirurgia , Meato Acústico Externo/cirurgia , Otite Externa/cirurgiaRESUMO
The gel polymer electrolyte (GPE) is the key to assembling high-performance solid-state supercapacitors (SSCs). The commercial poly(vinyl alcohol) (PVA) GPE has developed a reputation due to low ionic conductivity endowed by its high crystallinity and poor water retention capacity. In this work, density functional theory (DFT) calculations first revealed that the high crystallinity of PVA can be greatly disrupted by forming hydrogen bonds with natural agarose macromolecules. The hydrogen bond interpenetrated three-dimensional agarose/PVA network offers high water retention and large amounts of channels for movement of Li+ on hydroxyl oxygen atoms. So, an optimized formation of the Li-O coordinate bond (gLi-O(r) = 8.78) and improved diffusion coefficient of Li+ (DLi+) (71 × 10-6 cm2 s-1) were obtained in the agarose/PVA model. When assembled into SSCs, agarose/PVA-GPE with 2 M LiOAc (AP-GPE) exhibits an outstanding specific capacitance (697.22 mF cm-2 at 5 mA cm-2). The high water retention of agarose and large amounts of -OH groups in the agarose macromolecular can generate H2O by dehydration reaction, reducing the flammability of PVA and greatly enhancing the safety of SSCs.
RESUMO
The rational design and optimization of solid polymer electrolytes (SPEs) are critical for the application of safety and high efficiency lithium ion batteries (LIBs). Herein, we synthesized a novel poly(ethylene oxide) (PEO)-based SPE (PEO@AF SPE) with a cross-linking network by the introduction of alginate fiber (AF) membranes. Depending on the high-strength supporting AF skeleton and the cross-linking network formed by hydrogen bonds between the PEO matrix and AF skeleton, the obtained PEO@AF SPE exhibits an excellent tensile strength of 3.71 MPa, favorable heat resistance (close to 120 °C), and wide electrochemical stability window (5.2 V vs Li/Li+). Meanwhile, the abundant oxygen-containing groups in alginate macromolecular and the three-dimensional (3D) porous structure of the AF membrane can greatly increase Li+ anchor points and provide more Li+ migration pathways, leading to the enhancement of Li+ conduction and interfacial stability between the SPE and Li anode. Furthermore, the assembled LiFePO4/PEO@AF SPE/Li cells also exhibit satisfactory electrochemical performance. These results reveal that PEO incorporating with AFs can boost the mechanical strength, thermostability, and electrochemical properties of the SPE simultaneously. Furthermore, one will expect that the newly designed PEO@AF SPE with cross-linked networks thus provides the possibility for future applications of safety and high-performance LIBs.
RESUMO
The polar surface of (001) wurtzite-structured MnO possesses substantial electrostatic instabilities that facilitate a wurtzite to graphene-like sheet transformation during the lithiation/delithiation process when used in battery technologies. This transformation results in cycle instability and loss of cell efficiency. In this work, we synthesized MnO hexagonal sheets (HSs) possessing abundant oxygen vacancy defects (MnO-Vo HSs) by pyrolyzing and reducing MnCO3 HSs under an atmosphere of Ar/H2. The oxygen vacancies (Vos) were generated in the reduction process and have been characterized using a range of techniques: X-ray absorption fine structure, electron-spin resonance, X-ray absorption near edge structure, Artemis modeling, and R space Feff modeling. The data arising from these analyses inform us that the introduction of one Vo defect within each O atom layer can reduce the charge density by 3.2 × 10-19 C, balancing the internal nonzero dipole moment and rendering the wurtzite structure more stable, so inhibiting the change to a graphene-like structure. Density function theory calculations demonstrate that the incorporation of Vos sites significantly improves the charge accumulation around Li atoms and increases Li+ adsorption energies (-2.720 eV). When used as an anode material for lithium ion batteries, the MnO-Vo HSs exhibit high specific capacity (1228.3 mAh g-1 at 0.1 A g-1) and excellent cell cycling stabilities (â¼88.1% capacity retention after 1000 continuous charge/discharge cycles at 1.0 A g-1).
RESUMO
CONCLUSIONS: Improved appearance and hearing and increased efficiency are achievable for congenital microbia with defects of external auditory meatus (EAM) and middle ear. First the site of the external auditory meatus (EAM) orifice must be located according to the results of the temporal CT scan, then the auricle can be reconstructed employing the three-stage method. At the third stage, the EAM and middle ear can be reconstructed at the same time. OBJECTIVE: To select the best approach for reconstruction of congenital microtia with defects of the EAM and middle ear. PATIENTS AND METHODS: This study analyzed 498 cases (528 ears) of auricle reconstruction by the three-stage method and 77 cases (91 ears operation/120 ears) of EAM and middle ear reconstruction. RESULTS: For auricular reconstructions, the effects of reconstructed auricles were classified into four grades according to their structure verisimilitude and the bilateral symmetry. The majority of patients/families were satisfied. For 52 ears with normal movement of stapes, reconstructions of EAM and middle ear improved hearing by 15-50 dB, but long-term improvement was not ideal. In bilateral patients, 20 of 24 ears with reconstructed EAMs exhibited relapse of stenosis or atresia. For patients whose EAMs were reconstructed first, scar developed around the orifice and affected the skin flap and later auricle reconstruction, while reconstructing the auricle first sometimes resulted in the location of the EAM orifice deviating from an ideal position.
Assuntos
Orelha Externa/anormalidades , Orelha Externa/cirurgia , Orelha Média/anormalidades , Orelha Média/cirurgia , Procedimentos Cirúrgicos Otológicos/métodos , Procedimentos de Cirurgia Plástica/métodos , Adolescente , Adulto , Criança , Pré-Escolar , Cicatriz/etiologia , Constrição Patológica/etiologia , Surdez/etiologia , Surdez/cirurgia , Feminino , Perda Auditiva Condutiva-Neurossensorial Mista/etiologia , Perda Auditiva Condutiva-Neurossensorial Mista/cirurgia , Humanos , Masculino , Procedimentos Cirúrgicos Otológicos/efeitos adversos , Satisfação do Paciente , Procedimentos de Cirurgia Plástica/efeitos adversos , Recidiva , Retalhos CirúrgicosRESUMO
Triethylamine (TEA) gas sensors having excellent response and selectivity are in great demand to monitor the real environment. In this work, we have successfully prepared a hollow SnO2 microfiber by a unique sustainable biomass conversion strategy and shown that the microfiber can be used in a high-performance gas sensor. The sensor based on the hollow SnO2 microfiber shows a quick response/recovery toward triethylamine. The response of the hollow SnO2 microfiber is up to 49.5 when the concentration of TEA gas is 100 ppm. The limit of detection is as low as 2 ppm. Furthermore, the sensor has a relatively low optimal operation temperature of 270 °C, which is lower than those of many other reported sensors. The excellent sensing properties are largely attributed to the high sensitivity provided by SnO2 and the good permeability and conductivity of the one-dimensional hollow structure. Thus, the hollow SnO2 microfiber using sustainable biomass as a template is a significant strategy for a unique TEA gas sensor.