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Currently, most photoredox catalysis polymerization systems are limited by high excitation power, long polymerization time, or the requirement of electron donors due to the precise design of efficient photocatalysts still poses a great challenge. Herein, we propose a new approach: the creation of efficient photocatalysts having low ground state oxidation potentials and high excited state energy levels, along with through-space charge transfer (TSCT) induced intersystem crossing (ISC) properties. A cabazole-naphthalimide (NI) dyad (NI-1) characterized by long triplet excited state lifetime (τT=62â µs), satisfactory ISC efficiency (ΦΔ=54.3 %) and powerful reduction capacity [Singlet: E1/2 (PC+1/*PC)=-1.93â eV, Triplet: E1/2 (PC+1/*PC)=-0.84â eV] was obtained. An efficient and rapid polymerization (83 % conversion of 1â mM monomer in 30â s) was observed under the conditions of without electron donor, low excitation power (10â mW cm-2) and low catalyst (NI-1) loading (<50â µM). In contrast, the conversion rate was lower at 29 % when the reference catalyst (NI-4) was used for photopolymerization under the same conditions, demonstrating the advantage of the TSCT photocatalyst. Finally, the TSCT material was used as a photocatalyst in practical lithography for the first time, achieving pattern resolutions of up to 10â µm.
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The design of efficient heavy atom-free triplet photosensitizers (PSs) based on through bond charge transfer (TBCT) features is a formidable challenge due to the criteria of orthogonal donor-acceptor geometry. Herein, we propose using parallel (face-to-face) conformation carbazole-bodipy donor-acceptor dyads (BCZ-1 and BCZ-2) featuring through space intramolecular charge transfer (TSCT) process as efficient triplet PS. Efficient intersystem crossing (ΦΔ =61 %) and long-lived triplet excited state (τT =186â µs) were observed in the TSCT dyad BCZ-1 compared to BCZ-3 (ΦΔ =0.4 %), the dyad involving TBCT, demonstrating the superiority of the TSCT approach over conventional donor-acceptor system. Moreover, the transient absorption study revealed that TSCT dyads have a faster charge separation and slower intersystem crossing process induced by charge recombination compared to TBCT dyad. A long-lived charge-separated state (CSS) was observed in the BCZ-1 (τCSS =24â ns). For the first time, the TSCT dyad was explored for the triplet-triplet annihilation upconversion, and a high upconversion quantum yield of 11 % was observed. Our results demonstrate a new avenue for designing efficient PSs and open up exciting opportunities for future research in this field.
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OBJECTIVE: Because of their high metabolic activity and low-resting oxygen tension, the organs of the inner ear are vulnerable to hypoxia, a condition that occurs repetitively in obstructive sleep apnea-hypopnea syndrome (OSAHS). The present study aimed to investigate the inner ear function of patients with OSAHS. METHODS: A total of 58 patients with OSAHS (116 ears) and 20 adults without OSAHS were enrolled in the present study. The clinical features, such as air-conduction thresholds, auditory brainstem response (ABR, 11 times/s and 51 times/s stimulation rates), and distorted products otoacoustic emission (DPOAE), were evaluated and compared between these two groups. RESULTS: Air-conduction thresholds at 4 kHz and 8 kHz were higher in patients with OSAHS compared with controls (P < 0.001). At the rate of 11 times per second, biauricular wave I latencies and wave V latencies in the OSAHS group were longer than those in the control group (1.51 ± 0.13 vs. 1.33 ± 0.07 ms, P < 0.001; 5.65 ± 0.23 vs. 5.53 ± 0.23 ms, P = 0.0016). At the rate of 51 times per second, biauricular wave I latencies and wave V latencies in the OSAHS group were longer than those in the control group (1.64 ± 0.12 vs. 1.44 ± 0.06 ms, P = 0.0001; 5.92 ± 0.26 vs. 5.80 ± 0.18 ms, P = 0.0077). However, there was no significant difference in the wave I and wave V interval between these two groups (P = 0.10). DPOAE amplitude was significantly reduced in OSAHS patients, although no hearing loss was observed. CONCLUSION: High-frequency hearing loss was detected in adults with severe OSAHS, and wave I latencies and wave V latencies of ABR were prolonged.
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Orelha Interna/fisiopatologia , Apneia Obstrutiva do Sono/fisiopatologia , Adulto , Audiometria de Tons Puros , Limiar Auditivo/fisiologia , Orelha Interna/irrigação sanguínea , Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Feminino , Perda Auditiva de Alta Frequência/diagnóstico , Perda Auditiva de Alta Frequência/fisiopatologia , Humanos , Hipóxia/diagnóstico , Hipóxia/fisiopatologia , Isquemia/diagnóstico , Isquemia/fisiopatologia , Masculino , Emissões Otoacústicas Espontâneas/fisiologia , Tempo de Reação/fisiologia , Valores de Referência , Fatores de Risco , Apneia Obstrutiva do Sono/diagnósticoRESUMO
OBJECTIVE: Recognition of auditory brainstem response (ABR) waveforms may be challenging, particularly for older individuals or those with hearing loss. This study aimed to investigate deep learning frameworks to improve the automatic recognition of ABR waveforms in participants with varying ages and hearing levels. STUDY DESIGN: The research used a descriptive study design to collect and analyze pure tone audiometry and ABR data from 100 participants. SETTING: The research was conducted at a tertiary academic medical center, specifically at the Clinical Audiology Center of Tsinghua Chang Gung Hospital (Beijing, China). METHODS: Data from 100 participants were collected and categorized into four groups based on age and hearing level. Features from both time-domain and frequency-domain ABR signals were extracted and combined with demographic factors, such as age, sex, pure-tone thresholds, stimulus intensity, and original signal sequences to generate feature vectors. An enhanced Wide&Deep model was utilized, incorporating the Light-multi-layer perceptron (MLP) model to train the recognition of ABR waveforms. The recognition accuracy (ACC) of each model was calculated for the overall data set and each group. RESULTS: The ACC rates of the Light-MLP model were 97.8%, 97.2%, 93.8%, and 92.0% for Groups 1 to 4, respectively, with a weighted average ACC rate of 95.4%. For the Wide&Deep model, the ACC rates were 93.4%, 90.8%, 92.0%, and 88.3% for Groups 1 to 4, respectively, with a weighted average ACC rate of 91.0%. CONCLUSION: Both the Light-MLP model and the Wide&Deep model demonstrated excellent ACC in automatic recognition of ABR waveforms across participants with diverse ages and hearing levels. While the Wide&Deep model's performance was slightly poorer than that of the Light-MLP model, particularly due to the limited sample size, it is anticipated that with an expanded data set, the performance of Wide&Deep model may be further improved.
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Background: Sudden sensorineural hearing loss (SSNHL) is a prevalent emergency in ear, nose, and throat practice. Previous studies have demonstrated that intratympanic steroid therapy (IST) can serve as a salvage treatment for SSNHL after the failure of systemic steroid therapy (SST). Objective: This study aimed to analyze the efficacy of modified IST involving the insertion of a tympanic tube and gelfoam as a salvage treatment for patients with SSNHL, and to explore its associated factors. Methods: Totally, 74 patients who were aged 22-81 years with SSNHL were enrolled and allocated to either the control group (n = 25) or the treatment group (n = 49) based on their treatment modalities. All patients received SST lasting for at least 7 days. Subsequently, patients in the treatment group, after SST failure, underwent IST twice a week for 2-6 weeks, while the control group did not. Efficacy was assessed by the improvement in pure tone average at the affected frequency at the beginning and end of IST. Results: Hearing improvement in all patients after IST in the treatment group was 9.71 ± 14.84 dB, with significant improvement at affected frequencies (250-8000 Hz) compared with the control group (P < 0.05). The findings indicated the duration from the onset of SSNHL to the beginning of IST as an independent factor for pure tone average improvement after treatment (P = 0.002), whereas age, duration of SST, and time of IST were not (P > 0.05). Conclusion: The modified IST was demonstrated to be a safe and effective method as a salvage treatment for SSNHL. This study explored the efficacy of a modified IST approach, incorporating the utilization of tympanic tubes and gelfoam as key components. The findings underscore the advantages of gelfoam as a strategic drug carrier placed in the round window niche. By minimizing drug loss, extending action time, and increasing perilymph concentration, gelfoam enhances the therapeutic impact of IST, contributing to improved hearing outcomes in patients with SSNHL.
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Blebbistatin (Bleb) derivatives are a visible light photocage platform. During the photocleavage process, intramolecular charge transfer (ICT) and cationic intermediates play a decisive role. However, slow photolysis rate and low photolysis quantum yield are the main problems for Bleb's derivatives. Herein, by introducing a substituted OCH3 group at the para-position of the D ring, Bleb and Bleb derivatives with various leaving groups were synthesized and studied, and the photolysis performance was unveiled by steady-state spectra, photolysis rate experiments, photolysis quantum yield, and density functional theory calculations. Substituted OCH3 derivatives of Bleb may enhance the photolysis rate and increase the photolysis quantum yield because the electron-donating group can promote the ICT process and stabilize the cationic intermediate during the photolytic reaction. More generally, the insights gained from this structure-reactivity relationship may provide theoretical guidance and aid in the development of new highly efficient photoreactions.
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A growing body of research recently suggested the association between vestibular dysfunction and cognitive impairment. Meniere's disease (MD), a common clinical vestibular disorder, is usually accompanied by hearing loss and emotional stress, both of which may mediate the relationship between vestibule dysfunction and cognition. It is currently unknown whether the cognitive decline in MD patients could improve through treatment and how it relates to multiple clinical characteristics, particularly the severity of vertigo. Therefore, in the present study, the MD patients were followed up for 3, 6, and 12 months after treatment, and the cognitive functions, vertigo symptoms, and related physical, functional, and emotional effects of the patients were assessed using the Montreal Cognitive Assessment (MoCA) and Dizziness Handicap Inventory (DHI), aiming to explore the change in cognition before and after therapy and the correlation with various clinical features. It was found that cognitive decline in MD patients compared to healthy controls before therapy. Importantly, this cognitive impairment could improve after effective therapy, which was related to the severity of vertigo, especially in functional and physical impacts. Our results support the view that vestibular dysfunction is a potentially modifiable risk factor for cognitive decline.
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Notably, the intermolecular charge transfer between pyrene (Py) and benzophonenes (BPs) can significantly enhance the quantum yield of the triplet state of Py, which will convert Py from a fluorescence molecule to a phosphorescence molecule. The intermolecular charge transfer is confirmed by steady-state and time-resolved spectroscopy and theoretical study. Based on these foundations, Py is doped into BPs systems and a large Stokes-shift organic room temperature phosphorescence (ORTP) is observed. By using different benzophenone derivatives, a series of host-guest ORTP materials with different luminescent properties adjusted by intermolecular charge transfer features are developed. Fortunately, these host-guest ORTP systems from benzophenone derivatives and pyrene are readily fabricated, and the red gradient color lasting as long as 3 s is observed after removing UV excitation. This host-guest charge transfer strategy plays an important role in the mechanism of the luminous type shift. Our strategy paves the way to design ORTP materials conveniently and apply these materials in encryption and temperature alarm device.
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BACKGROUND: To investigate the effects of hypoxia degree and sleep duration on vestibular function in obstructive sleep apnea-hypopnea syndrome (OSAHS) patients. We made further study of the low oxygen levels of OSAHS and hypoxic duration on the impact of vestibular function, and further studied the OSAHS the longest apnea time and Vestibular Evoked Myogenic Potential (VEMP) abnormal rate and the relationship between the vestibular function of canal paralysis (CP). METHODS: A total of 87 OSAHS patients and 47 healthy individuals were enrolled in this study. There was no difference in gender, age and body mass index (BMI) values in matched experimental groups. Other diseases of other systems were excluded. All the participants completed sleepiness questionnaires (i.e., the Epworth sleepiness scale and the STOP-BANG questionnaire) and the Dizziness Handicap Inventory (DHI). Additionally, a caloric test, positional test, electrocochleogram, and VEMP test were administered to evaluate the vestibular function of all the participants. A polysomnography (PSG) was also performed. RESULTS: The current investigation generated the following three major findings: (I) there was a significant correlation between body mass index and canal paresis [CP; P=0.014, odds ratio (OR) =1.791, 95% confidence interval (CI): 1.125-2.851] and a significant positive correlation between the DHI score and VEMP results (P=0.0061, OR =3.667, 95% CI: 1.449-9.276); (II) the CP abnormality rate of the OSAHS group was significantly higher than that of the control group (P<0.05); (III) there was a significant correlation between the longest apnea duration and the DHI score (r=-0.191, P<0.05). CONCLUSIONS: The abnormality rate of the vestibular function of OSAHS patients is higher than that of healthy people. OSAHS intermittent hypoxia can affect vestibular function in the inner ear, and the longer the duration of prolonged hypoxia, the more serious the vestibular function damage.
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Apneia Obstrutiva do Sono , Sonolência , Estudos de Casos e Controles , Humanos , Hipóxia , Polissonografia , Apneia Obstrutiva do Sono/complicações , SíndromeRESUMO
BACKGROUND: This study aimed to analyze the abnormal rates of immune related factors in serum of sudden deafness (SD) patients, and to discuss the correlation between these indicators and the degree of pathological changes of SD patients. METHODS: From March 2018 to January 2021, 90 patients with SD who were hospitalized in Beijing Tsinghua Changgeng Hospital were enrolled as participants, and 60 healthy examinees served as the control group. Antinuclear antibody (ANA), anticardiolipin antibody immunoglobulin G (ACA-IgG), anticardiolipin antibody immunoglobulin M (ACA-IgM), and anti-ß-glucoprotein (anti-ß-GP) antibody were detected by enzyme-linked immunosorbent assay (ELISA). RESULTS: In the SD group, 43 participants were positive for ANA, while in the control group, only 9 participants were positive for ANA. The titer of antibodies was significantly higher in the SD group than in the control group. The differences in abnormal rates of ACA-IgG, ACA-IgM, and anti-ß-GP antibodies between the SD group and control group were not statistically significant (P>0.05). CONCLUSIONS: The pathogenesis of SD is correlated with autoimmune factors to a certain extent. In the course of clinical treatment, in addition to vasodilation, neurotrophic therapy, and thrombolytic therapy, patients can also be approached from the perspective of autoimmunity, which may achieve more ideal treatment effects.