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1.
Small ; 20(24): e2309609, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38150642

RESUMO

V-based solid solution materials hold a significant position in the realm of hydrogen storage materials because of its high hydrogen storage capacity. However, the current dehydrogenation temperature of V-based solid solution exceeds 350 °C, making it challenging to fulfill the appliance under moderate conditions. Here advancements in the hydrogen storage properties and related mechanisms of TiV1.1Cr0.3Mn0.6 + x LiAlH4 (x = 0, 5, 8, 10 wt.%) composites is presented. According to the first principle calculation analysis, the inclusion of Al and Li atoms will lower the binding energy of hydride, thus enhancing the hydrogen absorption reaction and significantly decreasing the activation difficulty. Furthermore, based on crystal orbital Hamilton population (COHP) analysis, the strength of the V─H and Ti─H bonds after doping LiAlH4 are reduced, leading to a decrease of the hydrogen release activation energy (Ea) for the V-based solid solution material, thus the hydrogen release process is easier to carry out. Additionally, the structure of doped LiAlH4 exhibits an outstanding hydrogen release rate of 2.001 wt.% at 323 K and remarkable cycling stability.

2.
Small ; : e2307965, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38050950

RESUMO

The interaction between fluorinated surface in the partially reduced nano-crystallite titanium dioxide (TiO2-x (F)) and MgH2 is studied for the first time. Compared with pristine MgH2 (416 °C), the onset desorption temperature of MgH2 +5 wt.% TiO2-x (F) composite can be dramatically lowered to 189 °C. In addition, the composite exhibits remarkable dehydrogenation kinetics, which can release 6.0 wt.% hydrogen thoroughly within 6 min at 250 °C. The apparent activation energy for dehydriding is decreased from 268.42 to 119.96 kJ mol-1 . Structural characterization and theoretical calculations indicate that the synergistic effect between multivalent Ti species, and the in situ formed MgF2 and MgF2-x Hx is beneficial for improving the hydrogen storage performance of MgH2 . Moreover, oxygen vacancies can accelerate the electron transportation and facilitate hydrogen diffusion. The study provides a novel perspective on the modification of MgH2 by fluorinated transition metal oxide catalyst.

3.
Angew Chem Int Ed Engl ; 62(8): e202216189, 2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36567260

RESUMO

Electrolyte design has become ever more important to enhance the performance of lithium-ion batteries (LIBs). However, the flammability issue and high reactivity of the conventional electrolytes remain a major problem, especially when the LIBs are operated at high voltage and extreme temperatures. Herein, we design a novel non-flammable fluorinated ester electrolyte that enables high cycling stability in wide-temperature variations (e.g., -50 °C-60 °C) and superior power capability (fast charge rates up to 5.0 C) for the graphite||LiNi0.8 Co0.1 Mn0.1 O2 (NCM811) battery at high voltage (i.e., >4.3 V vs. Li/Li+ ). Moreover, this work sheds new light on the dynamic evolution and interaction among the Li+ , solvent, and anion at the molecular level. By elucidating the fundamental relationship between the Li+ solvation structure and electrochemical performance, we can facilitate the development of high-safety and high-energy-density batteries operating in harsh conditions.

4.
Chemistry ; 27(20): 6283-6294, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33475219

RESUMO

Enzyme stereoselectivity control is still a major challenge. To gain insight into the molecular basis of enzyme stereo-recognition and expand the source of antiPrelog carbonyl reductase toward ß-ketoesters, rational enzyme design aiming at stereoselectivity inversion was performed. The designed variant Q139G switched the enzyme stereoselectivity toward ß-ketoesters from Prelog to antiPrelog, providing corresponding alcohols in high enantiomeric purity (89.1-99.1 % ee). More importantly, the well-known trade-off between stereoselectivity and activity was not found. Q139G exhibited higher catalytic activity than the wildtype enzyme, the enhancement of the catalytic efficiency (kcat /Km ) varied from 1.1- to 27.1-fold. Interestingly, the mutant Q139G did not lead to reversed stereoselectivity toward aromatic ketones. Analysis of enzyme-substrate complexes showed that the structural flexibility of ß-ketoesters and a newly formed cave together facilitated the formation of the antiPrelog-preferred conformation. In contrast, the relatively large and rigid structure of the aromatic ketones prevents them from forming the antiPrelog-preferred conformation.


Assuntos
Oxirredutases do Álcool , Álcoois , Oxirredutases do Álcool/genética , Oxirredutases do Álcool/metabolismo , Cetonas , Estereoisomerismo , Especificidade por Substrato
5.
ORL J Otorhinolaryngol Relat Spec ; 83(5): 319-326, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34237740

RESUMO

INTRODUCTION: Studies have shown that higher response levels can be obtained when the bone conduction stimulation position is closer to the cochlea. However, the morphological characteristics of round window niche and posterior tympanum in congenital aural atresia (CAA) and stenosis (CAS) patients were different from the normal. These affected the position of the cochlea at the cranial base. It was still unknown whether the distances from the cranium of CAA and CAS patients to the cochlea were the same as those of normal patients or not. OBJECTIVE: To measure distances from various points on the lateral surface of the cranium to the cochlea and the cranium thickness on these points among a CAA group, CAS group and normal control group, which may provide valuable information for the better position of bone conduction stimulation. METHODS: CT images of CAA, CAS patients and these patients' healthy sides were analyzed. Firstly, the Frankfurt horizontal plane (Pfrkt) was established. Secondly, a model of part of the cranium was three-dimensionally reconstructed. Then, the Pfrkt plane was rotated down 20, 30 and 40° according to the superior margin of the external auditory canal. At every angle, points 25, 30, 35 and 40 mm away from the superior margin of the external auditory canal were marked out on the surface of the model and recorded as P20A, P30A, P40A, P20B, etc. The spatial distances between the cranium and ipsilateral cochlea were defined as lengths of points on the surface of the model to the cochlea apex (CA), cochlear base (CB) and modiolus midpoint (MM), respectively, recorded as P20A/CA, P20A/CB, P20A/MM, P30A/CA, etc. Results and Conclusions: In all groups, the length of P20D/CA was the shortest compared to P30D/CA and P40D/CA (p < 0.05). The P20A/CB and P20A/MM were also the shortest (p < 0.05). When the Pfrkt plane was rotated down 30 and 40°, the results were the same as at 20° (p < 0.05). However, P20D, P30D and P40D were almost on the mastoid air cells. We suggest that the bone conduction stimulation position is placed closer to the ear, while avoiding the mastoid air cells in the CAA and CAS patients.


Assuntos
Cóclea , Tomografia Computadorizada por Raios X , Bochecha , Cóclea/diagnóstico por imagem , Constrição Patológica , Humanos , Processo Mastoide , Estudos Retrospectivos
6.
Small ; 16(26): e2000681, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32495487

RESUMO

SnO2 has been considered as a promising anode material for lithium-ion batteries (LIBs) and sodium ion batteries (SIBs), but challenging as well for the low-reversible conversion reaction and coulombic efficiency. To address these issues, herein, SnO2 quantum dots (≈5 nm) embedded in porous N-doped carbon matrix (SnO2 /NC) are developed via a hydrothermal step combined with a self-polymerization process at room temperature. The ultrasmall size in quantum dots can greatly shorten the ion diffusion distance and lower the internal strain, improving the conversion reaction efficiency and coulombic efficiency. The rich mesopores/micropores and highly conductive N-doped carbon matrix can further enhance the overall conductivity and buffer effect of the composite. As a result, the optimized SnO2 /NC-2 composite for LIBs exhibits a high coulombic efficiency of 72.9%, a high discharge capacity of 1255.2 mAh g-1 at 0.1 A g-1 after 100 cycles and a long life-span with a capacity of 753 mAh g-1 after 1500 cycles at 1 A g-1 . The SnO2 /NC-2 composite also displays excellent performance for SIBs, delivering a superior discharge capacity of 212.6 mAh g-1 at 1 A g-1 after 3000 cycles. These excellent results can be of visible significance for the size effect of the uniform quantum dots.

7.
Inorg Chem ; 56(16): 9794-9801, 2017 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-28758740

RESUMO

Novel hybrid metal oxides with advanced architectures are extensively pursued to achieve synergetic properties with respect to improved lithium-ion storage properties. Here, rationally designed yolk@shell or concave NiO-Co3O4@C (YNCC or CNCC) nanocubes have been fabricated by the simple and versatile thermolysis-induced transformation of metal-organic frameworks (MOFs), aimed at simultaneously addressing the capacity fade and conductivity deficiency of metal oxides. The as-prepared nanocomposites with plentiful hierarchical pores integrate the distinct functionalities of the ternary components: NiO and Co3O4 as the major active materials can guarantee high capacity, while carbon can improve the conductivity and accommodate volume changes. Benefitting from the intrinsic material and architecture features, the YNCC and CNCC nanocomposites deliver excellent electrochemical performances with high reversible specific capacity, superior cycling stability (803 and 870 mAh g-1 at 100 mA g-1 after 100 cycles), and good rate capability (339 and 398 mAh g-1 at 2 A g-1) as anode materials for lithium-ion batteries.

8.
Am J Otolaryngol ; 38(4): 422-427, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28390808

RESUMO

Objective To investigate characteristics of congenital aural stenosis (CAS) patients' external auditory canal (EAC) (position, length, orientation, etc.) and compare them with normal EAC. METHODS: CT images of normal people and CAS patient were utilized. We obtained coordinates of EAC landmarks. Then the Matlab program could calculate some anatomic parameters about EAC, including distances from central point of tympanic annulus (CA), central point of osseous EAC opening (CO), central point of cartilaginous EAC inside opening (CCi), central point of cartilaginous EAC outside opening (CCo) to the Frankfurt horizontal plane (Pfrkt), the median sagittal plane (Psag), the coronal plane (Pcor); orientations of EAC bendings; straight and arc lengths of EAC. RESULTS: Distances from CA, CO, CCi and CCo to Pfrkt were all shorter in CAS group than control group (p<0.05). The straight and arc lengths of cartilaginous EAC in CAS group were shorter than control group (p<0.05). Straight and arc lengths of EAC in CAS group were shorter than those in control group (p<0.05). The proportion of one bending in cartilaginous EAC in control group was significantly lower than CAS group (p<0.05). Orientations of EAC bendings in CAS group differed from those in control group (p<0.05). CONCLUSION: In addition to smaller diameters, compared with normal EAC, the position of CAS patients' osseous EAC was higher compared with the normal. The majority of CAS patients have a bending and downward slanting cartilaginous EAC. Orientations of EAC bending in CAS patients were different from normal. Besides, the length of CAS patients' cartilaginous EAC was shorter. However, there were no significant differences between CAS patients and normal people in length of osseous EAC. These differences in anatomic parameters could provide the basis for optimizing the meatoplasty.


Assuntos
Anormalidades Congênitas/patologia , Meato Acústico Externo/patologia , Orelha/anormalidades , Adolescente , Adulto , Pesos e Medidas Corporais , Estudos de Casos e Controles , Criança , Anormalidades Congênitas/diagnóstico por imagem , Constrição Patológica/patologia , Orelha/diagnóstico por imagem , Orelha/patologia , Meato Acústico Externo/diagnóstico por imagem , Feminino , Humanos , Masculino , Tomografia Computadorizada por Raios X , Adulto Jovem
9.
Chemistry ; 22(34): 12081-7, 2016 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-27406922

RESUMO

The preparation of novel one-dimensional core-shell Fe/Fe2 O3 nanowires as anodes for high-performance lithium-ion batteries (LIBs) is reported. The nanowires are prepared in a facile synthetic process in aqueous solution under ambient conditions with subsequent annealing treatment that could tune the capacity for lithium storage. When this hybrid is used as an anode material for LIBs, the outer Fe2 O3 shell can act as an electrochemically active material to store and release lithium ions, whereas the highly conductive and inactive Fe core functions as nothing more than an efficient electrical conducting pathway and a remarkable buffer to tolerate volume changes of the electrode materials during the insertion and extraction of lithium ions. The core-shell Fe/Fe2 O3 nanowire maintains an excellent reversible capacity of over 767 mA h g(-1) at 500 mA g(-1) after 200 cycles with a high average Coulombic efficiency of 98.6 %. Even at 2000 mA g(-1) , a stable capacity as high as 538 mA h g(-1) could be obtained. The unique composition and nanostructure of this electrode material contribute to this enhanced electrochemical performance. Due to the ease of large-scale fabrication and superior electrochemical performance, these hybrid nanowires are promising anode materials for the next generation of high-performance LIBs.

10.
Chemistry ; 22(4): 1467-74, 2016 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-26748911

RESUMO

Rational composite materials made from transition metal sulfides and reduced graphene oxide (rGO) are highly desirable for designing high-performance lithium-ion batteries (LIBs). Here, rGO-coated or sandwiched CoSx composites are fabricated through facile thermal sulfurization of metal-organic framework/GO precursors. By scrupulously changing the proportion of Co(2+) and organic ligands and the solvent of the reaction system, we can tune the forms of GO as either a coating or a supporting layer. Upon testing as anode materials for LIBs, the as-prepared CoSx -rGO-CoSx and rGO@CoSx composites demonstrate brilliant electrochemical performances such as high initial specific capacities of 1248 and 1320 mA h g(-1) , respectively, at a current density of 100 mA g(-1) , and stable cycling abilities of 670 and 613 mA h g(-1) , respectively, after 100 charge/discharge cycles, as well as superior rate capabilities. The excellent electrical conductivity and porous structure of the CoSx /rGO composites can promote Li(+) transfer and mitigate internal stress during the charge/discharge process, thus significantly improving the electrochemical performance of electrode materials.

11.
Chemistry ; 21(40): 14140-5, 2015 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-26251115

RESUMO

Binary metal oxides have been deemed as a promising class of electrode materials for high-performance lithium ion batteries owing to their higher conductivity and electrochemical activity than corresponding monometal oxides. Here, NiFe2O4 nanoplates consisting of nanosized building blocks have been successfully fabricated by a facile, large-scale NaCl and KCl molten-salt route, and the changes in the morphology of NiFe2O4 as a function of the molten-salt amount have been systemically investigated. The results indicate that the molten-salt amount mainly influences the diameter and thickness of the NiFe2O4 nanoplates as well as the morphology of the nanosized building blocks. Cyclic voltammetry (CV) and galvanostatic charge-discharge measurements have been conducted to evaluate the lithium storage properties of the NiFe2O4 nanoplates prepared with a Ni(NO3)2/Fe(NO3)3/KCl/NaCl molar ratio of 1:2:20:60. A high reversible capacity of 888 mAh g(-1) is delivered over 100 cycles at a current density of 100 mA g(-1). Even at a current density of 5000 mA g(-1) , the discharge capacity could still reach 173 mAh g(-1). Such excellent electrochemical performances of the NiFe2O4 nanoplates are contributed to the short Li(+) diffusion distance of the nanosized building blocks and the synergetic effect of the Ni(2+) and Fe(3+) ions.

12.
Chemistry ; 20(35): 11214-9, 2014 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-25044261

RESUMO

Hierarchical porous core-shell NiFe2O4@TiO2 nanorods have been fabricated with the help of hydrothermal synthesis, chemical bath deposition, and a subsequent calcinating process. The nanorods with an average diameter of 48 nm and length of about 300-600 nm turn out have a highly uniform morphology and are composed of nanosized primary particles. Owing to the synergistic effect of individual constituents as well as the hierarchical porous structure, the novel core-shell NiFe2O4@TiO2 nanorods exhibit superior electrochemical performance when evaluated as anode materials for lithium-ion batteries. At the current density of 100 mA g(-1), the composite exhibits a reversible specific capacity of 1034 mAh g(-1) up to 100 charge-discharge cycles, which is much higher than the uncoated NiFe2O4 nanorods. Even when cycled at 2000 mA g(-1), the discharge capacity could still be maintained at 358 mAh g(-1).

13.
Chemistry ; 20(52): 17523-9, 2014 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-25346404

RESUMO

Core-shell hierarchical porous carbon spheres (HPCs) were synthesized by a facile hydrothermal method and used as host to incorporate sulfur. The microstructure, morphology, and specific surface areas of the resultant samples have been systematically characterized. The results indicate that most of sulfur is well dispersed over the core area of HPCs after the impregnation of sulfur. Meanwhile, the shell of HPCs with void pores is serving as a retard against the dissolution of lithium polysulfides. This structure can enhance the transport of electron and lithium ions as well as alleviate the stress caused by volume change during the charge-discharge process. The as-prepared HPC-sulfur (HPC-S) composite with 65.3 wt % sulfur delivers a high specific capacity of 1397.9 mA h g(-1) at a current density of 335 mA g(-1) (0.2 C) as a cathode material for lithium-sulfur (Li-S) batteries, and the discharge capacity of the electrode could still reach 753.2 mA h g(-1) at 6700 mA g(-1) (4 C). Moreover, the composite electrode exhibited an excellent cycling capacity of 830.5 mA h g(-1) after 200 cycles.

14.
J Colloid Interface Sci ; 663: 961-970, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38447409

RESUMO

High-voltage medium-nickel low-cobalt lithium layered oxide cathode materials are intriguing for lithium-ion batteries (LIBs) applications because of their relatively low cost and high capacity. Unfortunately, high charging voltage induces bulk layered structure decline and interface environment deterioration, low cobalt content reduces lithium diffusion kinetics, severely limiting the performance liberation of this kind of cathode. Here, a multifunctional Al/Zr dual cation doping strategy is employed to enhance the electrochemical performance of LiNi0.6Co0.05Mn0.35O2 (NCM) cathode at a high charging cut-off voltage of 4.5 V. On the one hand, Al/Zr co-doping weakens the Li+/Ni2+ mixing through magnetic interactions due to the inexistence of unpaired electrons for Al3+ and Zr4+, thereby increasing the lithium diffusion rate and suppressing the harmful coexistence of H1 and H2 phases. On the other hand, they enhance the lattice oxygen framework stability due to strong Al-O and Zr-O bonds, inhibiting the undesired H2 to H3 phase transition and interface lattice oxygen loss, thereby enhancing the stability of the bulk structure and cathode-electrolyte interface. As a result, Al/Zr co-doped NCM (NCMAZ) shows a 94.2 % capacity retention rate after 100 cycles, while that of NCM is only 79.4 %. NCMAZ also exhibits better rate performance than NCM, with output capacities of 92 mAh/g and 59 mAh/g at a high current density of 5C, respectively. The modification strategy will make the high-voltage medium-nickel low-cobalt cathode closer to practical applications.

15.
Mater Horiz ; 11(8): 2032-2040, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38372566

RESUMO

Exploration of high-performance catalysts holds great importance for on-demand H2 production from ammonia borane (AB) hydrolysis. In this work, a hollow bowl-like porous carbon-anchored Ru-MgO hetero-structured nano-pair with high-intensity interfaces is made, using a tailored design approach. Consequently, the optimized catalyst shows AB hydrolysis activity with a turnover frequency value of 784 min-1 in aqueous media and 1971 min-1 in alkaline solvent. Robust durability is also achieved, with slight deactivation after a ten-cycle test. Combined experimental and theoretical calculations validate the positive function of the interface between Ru and MgO for facilitating H transfer and boosting water activation, thus leading to improved AB hydrolysis performance. This study could be valuable in guiding the upgradation of Ru catalytic systems, to advance their practical applications.

16.
Braz J Otorhinolaryngol ; 89(3): 477-484, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36805347

RESUMO

OBJECTIVES: The aim of this study was to examine the changes in gray matter in nasopharyngeal carcinoma patients with normal hearing (Group 1) and nasopharyngeal carcinoma patients with hearing loss (Group 2) after radiotherapy using voxel-based morphological analysis and to analyze the relationship with the radiation doses of the temporal lobe. METHODS: 21 patients in Group 1, 14 patients in Group 2, and 21 healthy volunteers were selected. All participants underwent an otologic examination and three-dimensional magnetization preparatory rapid acquisition gradient echo sequence scan. The correlation between the variation of whole brain gray matter volume and the doses of the temporal lobe was analyzed by Data Processing & Analysis for Brain Imaging software. RESULTS: Compared with the normal control group, the brain areas with reduced gray matter volume in nasopharyngeal carcinoma patients after radiotherapy were mainly in the left posterior cerebellar lobe (T = -8.797), left insular lobe (T = -7.96), and the right insular lobe (T = -6.632). Compared to Group 1, the brain areas of Group 2 patients with reduced gray matter volume were mainly in the left superior temporal gyrus (T = -2.366), left olfactory bulb (T = -2.52), left Rolandic operculum (T = -2.431), and right olfactory bulb (T = -3.100). Compared with Group 1, the brain areas of Group 2 patients with increased gray matter volume were mainly in the left calcarine sulcus (T=3.425) and right calcarine sulcus (T=3.169). There were no correlations between the changes of brain gray matter volume and the radiation doses of the temporal lobe in both Group 1 and Group 2. CONCLUSIONS: The radiotherapy may cause the changes of brain areas associated with cognitive function in nasopharyngeal carcinoma in a long-term follow-up. At the same time, nasopharyngeal carcinoma patients with the radiation-induced hearing loss had abnormal gray matter volumes in the auditory center and other sensory centers. Our findings might provide new understanding into the pathogenesis of radiation-induced brain damage in normal-appearing brain tissue. Yet this exploratory study should be taken with caution.


Assuntos
Perda Auditiva , Neoplasias Nasofaríngeas , Humanos , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Carcinoma Nasofaríngeo/radioterapia , Carcinoma Nasofaríngeo/patologia , Seguimentos , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Imageamento por Ressonância Magnética , Neoplasias Nasofaríngeas/diagnóstico por imagem , Neoplasias Nasofaríngeas/radioterapia , Neoplasias Nasofaríngeas/patologia
17.
Auris Nasus Larynx ; 50(1): 57-61, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35649956

RESUMO

OBJECTIVE: The auditory steady-state response (ASSR) amplitudes fall in the presence of contralateral noise. However, whether and to what extent medial olivocochlear (MOC) activity involves in contralateral suppression of ASSR remain unclear. Therefore, we assess the role of MOC activity in contralateral suppression of ASSR. METHODS: Mice were treated with strychnine to completely eliminate MOC activity and then measured ASSR amplitudes in the presence of contralateral noise. RESULTS: The contralateral noise reduces ASSR amplitudes at some stimulus intensity. After treating with the strychnine to eliminate MOC activity, ASSR amplitudes recovered again. CONCLUSIONS: MOC activity participated in contralateral suppression of ASSR.


Assuntos
Ruído , Estricnina , Animais , Camundongos , Estimulação Acústica , Estricnina/farmacologia , Cóclea/fisiologia , Núcleo Olivar/fisiologia
18.
Neuroreport ; 33(18): 786-790, 2022 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-36367795

RESUMO

Our purpose was to study the expression of purinergic receptors 2X2 (P2X2) and purinergic receptors 2X3 (P2X3) in spiral ganglion neurons (SGNs), the afferent nerves of medial olivocochlear (MOC) reflex, after long-term moderate noise exposure, and its relationship with the enhancement of MOC reflex. Mice were exposed a moderate broadband noise for 4 weeks consecutively. Then mouse hearing functions, including threshold auditory brainstem responses, distortion-product otoacoustic emissions, and MOC reflex, were evaluated and the expression of P2X2 and P2X3 on SGNs were assessed by cochlear immunofluorescence. AF-353 was injected before each noise exposure. Four weeks later, mice were also tested for hearing functions and expression of P2X2 and P2X3 on SGNs. The long-term moderate noise strengthened MOC reflex, and AF-353 reduced it in mice and P2X3 expression on SGNs increased after long-term moderate noise exposure, and AF-353 can downregulate it. The P2X3 on SGNs of mice increased after long-term moderate noise exposure, and the upregulation of it mediated the enhancement of MOC reflex.


Assuntos
Cóclea , Gânglio Espiral da Cóclea , Camundongos , Animais , Cóclea/fisiologia , Reflexo/fisiologia , Neurônios , Receptores Purinérgicos , Estimulação Acústica
19.
Anat Rec (Hoboken) ; 305(2): 436-445, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34050614

RESUMO

Given the limited source of human external auditory canal (EAC) skin, animal experiments remain an important approach for studying functional EAC reconstruction. However, differences between humans and animals in terms of the general EAC structure, histological characteristics of EAC skin, and cell markers of its specific glands in cartilaginous EAC skin remain unknown. We compared the characteristics of the EAC between humans and large animals, as a basis for appropriate animal model selection. Temporal bone computed tomography was used to compare the EACs of humans, goats, pigs, and dogs. EAC skin samples were harvested and their histological characteristics evaluated. The skin's ultrastructure and the histological structure of specific glands and cell markers related to cell phenotype and function were further identified. The EAC structure in goats was similar to that in humans in terms of diameter, length, and cartilaginous segment ratio of the EAC, while that of pigs and dogs differed markedly. Furthermore, histological evaluation showed that there were abundant ceruminous and sebaceous glands in the goat's cartilaginous skin, while dogs and pigs showed notably fewer of these glands in cartilaginous skin than humans. Nevertheless, ceruminous glands in all species studied showed similar expression of cell biomarkers and secretion function. Goats might have advantages in terms of surgery and reconstruction of the functional EAC skin compared to dogs and pigs and can be a useful candidate for ceruminous gland cell sources.


Assuntos
Meato Acústico Externo , Pele , Animais , Modelos Animais de Doenças , Cães , Meato Acústico Externo/diagnóstico por imagem , Cabras , Humanos , Suínos , Tomografia Computadorizada por Raios X
20.
ACS Appl Mater Interfaces ; 13(49): 58871-58884, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34859994

RESUMO

High-voltage high-nickel low-cobalt lithium layered oxide cathodes show great application prospects for lithium-ion batteries due to their low cost and high capacity. However, deterioration of the bulk structure and the electrode-electrolyte interface will significantly endanger the cycle life and thermal stability of the battery as the nickel content and voltage increase. We present here a lattice doping strategy to greatly improve the cell performance by doping a small dose of Ti (2 mol %) in LiNi0.6Co0.05Mn0.35O2. Through density functional theory calculations, we know that the diffusion energy barrier of Li+ decreases and the activation energy of surface lattice oxygen atom loss increases after Ti doping, thereby improving the rate performance and inhibiting the undesired phase transition. The battery in situ X-ray diffraction (XRD) pattern demonstrates that Ti doping tunes the H1-H2 phase-transition process from a two-phase reaction to a single-phase reaction and inhibits the undesired H2-H3 phase transition, minimizing the mechanical degradation. The variable temperature in situ XRD reveals delayed phase-transition temperature to improve thermal stability. These improvements can be attributed to Ti doping to passivate the reactivity of the layered oxide cathode, which is fundamentally related to the strong Ti-O bond and no unpaired electrons for Ti4+. This work provides valuable strategic guidelines for the use of high-voltage high-nickel low-cobalt cathodes in lithium-ion batteries.

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