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1.
Materials (Basel) ; 17(10)2024 May 07.
Article in English | MEDLINE | ID: mdl-38793240

ABSTRACT

Metal halide perovskite semiconductors have emerged as promising materials for various optoelectronic applications due to their unique crystal structure and outstanding properties. Among different forms, perovskite nanowires (NWs) offer distinct advantages, including a high aspect ratio, superior crystallinity, excellent light absorption, and carrier transport properties, as well as unique anisotropic luminescence properties. Understanding the formation mechanism and structure-property relationship of perovskite NWs is crucial for exploring their potential in optoelectronic devices. In this study, we successfully synthesized all-inorganic halide perovskite NWs with high aspect ratios and an orthorhombic crystal phase using the hot-injection method with controlled reaction conditions and surface ligands. These NWs exhibit excellent optical and electrical properties. Moreover, precise control over the halogen composition through a simple anion exchange process enables the tuning of the bandgap, leading to fluorescence emission, covering a wide range of colors across the visible spectrum. Consequently, these perovskite NWs hold great potential for efficient energy conversion and catalytic applications in photoelectrocatalysis.

2.
Materials (Basel) ; 17(7)2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38612121

ABSTRACT

As a direct band gap semiconductor, perovskite has the advantages of high carrier mobility, long charge diffusion distance, high defect tolerance and low-cost solution preparation technology. Compared with traditional metal halide perovskites, which regulate energy band and luminescence by changing halogen, perovskite quantum dots (QDs) have a surface effect and quantum confinement effect. Based on the LaMer nucleation growth theory, we have synthesized CsPbBr3 QDs with high dimensional homogeneity by creating an environment rich in Br- ions based on the general thermal injection method. Moreover, the size of the quantum dots can be adjusted by simply changing the reaction temperature and the concentration of Br- ions in the system, and the blue emission of strongly confined pure CsPbBr3 perovskite is realized. Finally, optical and electrochemical tests suggested that the synthesized quantum dots have the potential to be used in the field of photocatalysis.

3.
RSC Adv ; 13(5): 3071-3078, 2023 Jan 18.
Article in English | MEDLINE | ID: mdl-36756424

ABSTRACT

The transition-metal centered boron molecular wheels have attracted the attention of chemists. The highest deca-coordination number for central metal atoms was observed in D 10h Ta©B10 - and Nb©B10 - molecular wheels. Here, we report a theoretical study of La©B8C4 q (q = +1, 0, -1) clusters with the dodeca-coordinated La atom. The La©B8C4 q clusters adopt fascinating molecular wheel structures, showing a La atom enclosed by a perfect B8C4 monocyclic ring. The cationic La©B8C4 + cluster has a C 4v symmetry with the distinctly out-of-plane distortion of the La atom (0.70 Å), which is gradually flattened by the sequential reduction reaction. The distortion of the La atom from the plane in the neutral La©B8C4 cluster decreases to 0.46 Å. The La©B8C4 - species turns out to be perfectly planar. Chemical bonding analyses indicate that the neutral La©B8C4 and anionic La©B8C4 - possess 10σ and 9π/10π double aromaticity, respectively, obeying the principle of double aromaticity. However, the cationic La©B8C4 + has 10σ and 8π conflicting aromaticity, representing a counterexample in planar hyper-coordinated molecular wheels. The dodeca-coordination number in La©B8C4 q (q = +1, 0, -1) clusters is unprecedented, which provides a new idea and concept for searching planar hyper-coordinated systems.

4.
Nature ; 609(7929): 925-930, 2022 09.
Article in English | MEDLINE | ID: mdl-36171386

ABSTRACT

The paradigmatic example of a topological phase of matter, the two-dimensional Chern insulator1-5, is characterized by a topological invariant consisting of a single integer, the scalar Chern number. Extending the Chern insulator phase from two to three dimensions requires generalization of the Chern number to a three-vector6,7, similar to the three-dimensional (3D) quantum Hall effect8-13. Such Chern vectors for 3D Chern insulators have never been explored experimentally. Here we use magnetically tunable 3D photonic crystals to achieve the experimental demonstration of Chern vectors and their topological surface states. We demonstrate Chern vector magnitudes of up to six, higher than all scalar Chern numbers previously realized in topological materials. The isofrequency contours formed by the topological surface states in the surface Brillouin zone form torus knots or links, whose characteristic integers are determined by the Chern vectors. We demonstrate a sample with surface states forming a (2, 2) torus link or Hopf link in the surface Brillouin zone, which is topologically distinct from the surface states of other 3D topological phases. These results establish the Chern vector as an intrinsic bulk topological invariant in 3D topological materials, with surface states possessing unique topological characteristics.

5.
Front Neurol ; 13: 980150, 2022.
Article in English | MEDLINE | ID: mdl-36090873

ABSTRACT

Objectives: This study aims to explore the relationship between bone-turnover biomarkers and the recovery of SSNHL to provide clues for further improvements in etiological research and predictors. Methods: The medical history, hearing thresholds, biomarkers of bone-turnover, and related hormones of 117 SSNHL patients were collected prospectively between August 2018 and December 2021. Linear correlation and logistic regression models were applied to examine the association between bone-turnover biomarkers and the prognosis of SSNHL. Results: Age, the incidence of vertigo, pure tone average of the impaired frequencies (PTAimpairedfre), and the levels of bone turnover [including alkaline phosphatase (ALP), ß-carboxy terminal crosslinked telopeptide of type 1 collagen (ß-CTX), and N-terminal-midfragment of osteocalcin (N-MID)] were higher in the nonresponders than responders (P < 0.05). Logistic regression showed that the age (OR = 1.035, P = 0.027), time to treatment (OR = 1.157, P = 0.038), PTAimpairedfre (OR = 1.031, P = 0.008), and ß-CTX (OR = 1.004, P = 0.001) were independent risk factors for the prognosis of SSNHL. In the women SSNHL subgroup, age, postmenopause percentage, PTAimpairedfre, the activity of ALP, levels of ß-CTX, and N-MID were significantly higher in the nonresponders than the responders (P < 0.05). Compared to the men SSNHL subgroup, ß-CTX has a higher correlation coefficient and predictive efficiency in the women SSNHL subgroup, and logistic regression showed that ß-CTX (OR = 1.004, P = 0.004) was an independent risk factor for the women SSNHL. Conclusions: Bone-turnover biomarkers are risk factors for poor prognosis in SSNHL, especially ß-CTX. The differences were significant in women SSNHL, which may be related to the rapid regression of estrogen after menopause that leads to the occurrence of osteoporosis with a high conversion rate.

6.
Front Endocrinol (Lausanne) ; 12: 763021, 2021.
Article in English | MEDLINE | ID: mdl-34867805

ABSTRACT

Glycosylated hemoglobin A1c (HbA1c) level has strong relevance to microvascular disorders, which are also thought to be the current main aspect of sudden sensorineural hearing loss (SSNHL), so we aim to elucidate the association of the HbA1c level with the severity, types, and prognosis of SSNHL. In this study, comparative analyses based on propensity score matching of the severity, types, and prognosis of SSNHL with the HbA1c level in 116 patients diagnosed as SSNHL were conducted, where they were divided into diabetes mellitus (DM) group and non-DM group. We finally found that, among patients with SSNHL, diabetic patients had a higher HbA1c level, more severe hearing loss, and poorer prognosis than non-diabetic patients. The HbA1c level was found to be significantly correlated with the severity and types of SSNHL, while no strong relevance was found between the higher HbA1c level and the poorer prognosis of SSNHL.


Subject(s)
Diabetes Mellitus/blood , Diabetes Mellitus/epidemiology , Glycated Hemoglobin/metabolism , Hearing Loss, Sensorineural/blood , Hearing Loss, Sensorineural/epidemiology , Adult , Aged , Diabetes Mellitus/diagnosis , Female , Follow-Up Studies , Hearing Loss, Sensorineural/diagnosis , Hearing Loss, Sudden/blood , Hearing Loss, Sudden/diagnosis , Hearing Loss, Sudden/epidemiology , Hearing Tests/methods , Humans , Male , Middle Aged , Prospective Studies , Young Adult
7.
Front Neurosci ; 15: 744959, 2021.
Article in English | MEDLINE | ID: mdl-34924928

ABSTRACT

Objectives: Mandarin-speaking users of cochlear implants (CI) perform poorer than their English counterpart. This may be because present CI speech coding schemes are largely based on English. This study aims to evaluate the relative contributions of temporal envelope (E) cues to Mandarin phoneme (including vowel, and consonant) and lexical tone recognition to provide information for speech coding schemes specific to Mandarin. Design: Eleven normal hearing subjects were studied using acoustic temporal E cues that were extracted from 30 continuous frequency bands between 80 and 7,562 Hz using the Hilbert transform and divided into five frequency regions. Percent-correct recognition scores were obtained with acoustic E cues presented in three, four, and five frequency regions and their relative weights calculated using the least-square approach. Results: For stimuli with three, four, and five frequency regions, percent-correct scores for vowel recognition using E cues were 50.43-84.82%, 76.27-95.24%, and 96.58%, respectively; for consonant recognition 35.49-63.77%, 67.75-78.87%, and 87.87%; for lexical tone recognition 60.80-97.15%, 73.16-96.87%, and 96.73%. For frequency region 1 to frequency region 5, the mean weights in vowel recognition were 0.17, 0.31, 0.22, 0.18, and 0.12, respectively; in consonant recognition 0.10, 0.16, 0.18, 0.23, and 0.33; in lexical tone recognition 0.38, 0.18, 0.14, 0.16, and 0.14. Conclusion: Regions that contributed most for vowel recognition was Region 2 (502-1,022 Hz) that contains first formant (F1) information; Region 5 (3,856-7,562 Hz) contributed most to consonant recognition; Region 1 (80-502 Hz) that contains fundamental frequency (F0) information contributed most to lexical tone recognition.

8.
Front Neurol ; 12: 747561, 2021.
Article in English | MEDLINE | ID: mdl-34733230

ABSTRACT

Objectives: As a common otology emergency, sudden sensorineural hearing loss (SSNHL) has a great impact on quality of life. The diagnosis and treatment of SSNHL remain challenging. This study aims to identify and investigate the association of liver functions with SSNHL. Methods: A total of 135 SSNHL patients and 135 sex- and age-matched controls were prospectively enrolled. The baseline and clinical characteristics, along with liver function levels of participators, were collected. Linear correlation, logistic regression, and receiving operator characteristic curve analysis tests were applied to examine the association between liver function levels and SSNHL. Results: There were no differences in baseline characteristics between SSNHL and control groups. The albumin (ALB) level of the SSNHL group was significantly lower than that in the control group (p < 0.001). The logistic regression showed that the low ALB level may be a predictive factor of SSNHL with an adjusted OR of 0.809 (95% CI, 0.742-0.882, p < 0.001). By comparing the indicators of different prognosis groups, we found that the effective group had a significantly lower hearing impair onset and higher ALB (p = 0.001) and AGR (p = 0.003) levels than the ineffective group. Logistic regression revealed that the hearing level onset (OR, 0.976; 95% CI, 0.956-0.997; p = 0.026) and ALB level (OR, 1.181; 95% CI, 1.071-1.301; p = 0.001) showed strong associations with treatment outcome. Conclusions: Lower ALB levels, within the normal ranges, were associated with the occurrence and unfavorable outcome of SSNHL. However, further research on the underlying mechanisms needs to be conducted.

9.
Front Neurosci ; 15: 670192, 2021.
Article in English | MEDLINE | ID: mdl-34335156

ABSTRACT

OBJECTIVES: Acoustic temporal envelope (E) cues containing speech information are distributed across all frequency spectra. To provide a theoretical basis for the signal coding of hearing devices, we examined the relative weight of E cues in different frequency regions for Mandarin disyllabic word recognition in quiet. DESIGN: E cues were extracted from 30 continuous frequency bands within the range of 80 to 7,562 Hz using Hilbert decomposition and assigned to five frequency regions from low to high. Disyllabic word recognition of 20 normal-hearing participants were obtained using the E cues available in two, three, or four frequency regions. The relative weights of the five frequency regions were calculated using least-squares approach. RESULTS: Participants correctly identified 3.13-38.13%, 27.50-83.13%, or 75.00-93.13% of words when presented with two, three, or four frequency regions, respectively. Increasing the number of frequency region combinations improved recognition scores and decreased the magnitude of the differences in scores between combinations. This suggested a synergistic effect among E cues from different frequency regions. The mean weights of E cues of frequency regions 1-5 were 0.31, 0.19, 0.26, 0.22, and 0.02, respectively. CONCLUSION: For Mandarin disyllabic words, E cues of frequency regions 1 (80-502 Hz) and 3 (1,022-1,913 Hz) contributed more to word recognition than other regions, while frequency region 5 (3,856-7,562) contributed little.

10.
Sci Rep ; 11(1): 13879, 2021 Jul 06.
Article in English | MEDLINE | ID: mdl-34230596

ABSTRACT

Quantum image representation (QIR) is a necessary part of quantum image processing (QIP) and plays an important role in quantum information processing. To address the problems that NCQI cannot handle images with inconsistent horizontal and vertical position sizes and multi-channel image processing, an improved color digital image quantum representation (INCQI) model based on NCQI is proposed in this paper. The INCQI model can process color images and facilitate multi-channel quantum image transformations and transparency information processing of images using auxiliary quantum bits. In addition, the quantum image control circuit was designed based on INCQI. And quantum image preparation experiments were conducted on IBM Quantum Experience (IBMQ) to verify the feasibility and effectiveness of INCQI quantum image preparation. The prepared image information was obtained by quantum measurement in the experiment, and the visualization of quantum information was successfully realized. The research in this paper has some reference value for the research related to QIP.

11.
Article in Chinese | MEDLINE | ID: mdl-33794643

ABSTRACT

As isolated anatomical position, limited labyrinthine artery supply, and blood-labyrinth barrier hampers systemic drug delivery to the inner ear. The efficient concentration of drug treatment is unsatisfactory and there's possible side effects after systemic administration. Intratympanic injection of drug can bypass the blood-labyrinth and permeated to the hair cells or synaptic area via the round-or oval window of the cochlea. Efficacy and safety of pharmacotherapy has become increasingly relied on the inner ear delivery carrier system. The goal of this review focus on the anatomical barrier that need to be overcome in the intratympanic applications, the improvement of drug retention and specific targets, and the safety of novel drug carriers, these emerging strategies of local drug delivery promise novel and better guidance for the clinical application.


Subject(s)
Drug Carriers , Ear, Inner , Cochlea , Drug Delivery Systems , Round Window, Ear
12.
Front Cell Dev Biol ; 9: 642946, 2021.
Article in English | MEDLINE | ID: mdl-33732708

ABSTRACT

Noise-induced hearing loss (NIHL) is characterized by cellular damage to the inner ear, which is exacerbated by inflammation. High-mobility group box 1 (HMGB1), a representative damage-associated molecular pattern (DAMP), acts as a mediator of inflammation or an intercellular messenger according to its cellular localization. Blocking or regulating HMGB1 offers an attractive approach in ameliorating NIHL. However, the precise therapeutic intervention must be based on a deeper understanding of its dynamic molecular distribution and function in cochlear pathogenesis after acoustic trauma. Here, we have presented the spatiotemporal dynamics of the expression of HMGB1, exhibiting distribution variability in specific cochlear regions and cells following noise exposure. After gene manipulation, we further investigated the characteristics of cellular HMGB1 in HEI-OC1 cells. The higher cell viability observed in the HMGB1 knocked-down group after stimulation with H2O2 indicated the possible negative effect of HMGB1 on cellular lifespan. In conclusion, this study demonstrated that HMGB1 is involved in NIHL pathogenesis and its molecular biology has essential and subtle influences, preserving a translational potential for pharmacological intervention.

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