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1.
Artigo em Inglês | MEDLINE | ID: mdl-38083131

RESUMO

Meal supervision for post-stroke dysphagia patients significantly improves prognosis during rehabilitation. Aspiration often occurs during meals, which may further incur aspiration pneumonia. Therefore, it's necessary to know the patient's swallowing ability as well as the occurrence of cough. Recently, some researchers have detected swallowing or coughing with audio signals and have made remarkable achievements. However, the users need to stay in quiet environments or wear uncomfortable cervical auscultation devices because the signals generated by swallowing are weak. In this work, we present MealCoach, a system that utilizes a contact microphone to collect high-quality signals to identify the events during meals. We take advantage of the insensitivity of contact microphones to ambient noise for free-living environment supervision. After balancing the wearing experience and identification accuracy, we elaborately select the optimal site to leverage the unique characteristics of cricoid cartilage movement during meals to accurately identify swallowing, coughing, speaking, and other events during meals. We collected data from thirty PSD patients in the hospital and evaluated our system, and the results demonstrate that MealCoach achieves a mean classification accuracy of 95.4%.


Assuntos
Transtornos de Deglutição , Acidente Vascular Cerebral , Humanos , Transtornos de Deglutição/diagnóstico , Transtornos de Deglutição/etiologia , Deglutição , Acidente Vascular Cerebral/complicações , Pescoço , Tosse/etiologia
2.
Behav Sci (Basel) ; 13(8)2023 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-37622786

RESUMO

Smartphone addiction is widespread among college students. Physical exercise and core self-evaluation are two potential factors that may influence smartphone addiction. This study aimed to investigate the relationship between physical exercise and college students' smartphone addiction, as well as the mediating effect of core self-evaluation. Here, 643 undergraduate university students are surveyed via questionnaire using the Physical Activity Rating Scale, the Smartphone Addiction Scale for College Students, and the Core Self-Evaluations Scale. The participants include 363 males (56.5%) and 280 females (43.5%), with ages ranging from 17 to 25 years old (mean = 19.68, SD = 1.40). The obtained data are analyzed using SPSS26.0 and the PROCESS plugins. The main findings of the study are as follows: (1) There is a significant negative correlation between physical exercise and smartphone addiction (r = -0.30, p < 0.01), a significant positive correlation between physical exercise and core self-evaluation (r = 0.25, p < 0.01), and a significant negative correlation between core self-evaluation and smartphone addiction (r = -0.52, p < 0.01). (2) There is a mediating effect of core self-evaluation between physical exercise and smartphone addiction. The current study can provide new evidence for the impact of physical exercise on smartphone addiction and highlights the importance of core self-evaluation. Moreover, research ideas and methodological guidance are provided for the following interventions and treatments targeting college students' smartphone addiction.

3.
Digit Health ; 9: 20552076231183548, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37434729

RESUMO

Objective: This study aims to establish a real-time dynamic monitoring system for silent aspiration (SA) to provide evidence for the early diagnosis of and precise intervention for SA after stroke. Methods: Multisource signals, including sound, nasal airflow, electromyographic, pressure and acceleration signals, will be obtained by multisource sensors during swallowing events. The extracted signals will be labeled according to videofluoroscopic swallowing studies (VFSSs) and input into a special dataset. Then, a real-time dynamic monitoring model for SA will be built and trained based on semisupervised deep learning. Model optimization will be performed based on the mapping relationship between multisource signals and insula-centered cerebral cortex-brainstem functional connectivity through resting-state functional magnetic resonance imaging. Finally, a real-time dynamic monitoring system for SA will be established, of which the sensitivity and specificity will be improved by clinical application. Results: Multisource signals will be stably extracted by multisource sensors. Data from a total of 3200 swallows will be obtained from patients with SA, including 1200 labeled swallows from the nonaspiration category from VFSSs and 2000 unlabeled swallows. A significant difference in the multisource signals is expected to be found between the SA and nonaspiration groups. The features of labeled and pseudolabeled multisource signals will be extracted through semisupervised deep learning to establish a dynamic monitoring model for SA. Moreover, strong correlations are expected to be found between the Granger causality analysis (GCA) value (from the left middle frontal gyrus to the right anterior insula) and the laryngeal rise time (LRT). Finally, a dynamic monitoring system will be established based on the former model, by which SA can be identified precisely. Conclusion: The study will establish a real-time dynamic monitoring system for SA with high sensitivity, specificity, accuracy and F1 score.

4.
Carbohydr Polym ; 253: 117260, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33278942

RESUMO

Assembling cellulose nanocrystals (CNCs) can induce photonic emission. It is free of photobleaching and aggregation-induced quenching, which has great potential in the application of information security. However, the emission suffers a low emission quantum yield (EQY), and the assembly mediate (solvents) can affect the assembly or the emission. Herein, we established a strategy of nanoscale assembly to integrate emission enhancement methods and improve the assembly induced emission. Via controlling the CNC assembly in the nanoscale space of metal-organic frameworks (MOFs), the EQY of CNC array primarily increased by 50 %. When carbon nanodots were further incorporated in MOF, their plasmonic resonance could enhance the emission coupling rate and offset the loss in emission intensity from the extinction of MOF particles, leading to a 6.9-time increase in EQY (to 64.84 %). Such a high EQY from two emission enhancement mechanisms make this nanomaterial able to hide and present photonic information effectively.

5.
Phys Chem Chem Phys ; 22(37): 21445-21452, 2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-32945293

RESUMO

The development of organic room-temperature phosphorescence (RTP) is accompanied by opportunities and challenges. RTP from crystal polymorphism has aroused much attention, due to the significant different photophysical characteristics and intermolecular packings found in the same molecule with different crystal phases. Herein, we report three organic molecules BP-o-BO, BP-m-BO, and BP-p-BO, in which two crystal polymorphisms of BP-p-BO are successfully cultivated with different emission properties. BP-p-BO-A exhibits bright cyan photoluminescence (PL) with a quantum yield of 11.3% and a distinct RTP with a lifetime of 17.1 ms, which is much higher than the deep blue PL of BP-p-BO-B (6.9%) and the corresponding RTP lifetime of 3.3 ms. Crystal structure analyses indicate that the different emission properties can be ascribed to the different intermolecular packing, further demonstrating the essential role of molecular packing in the designing of RTP materials.

6.
Angew Chem Int Ed Engl ; 59(45): 20161-20166, 2020 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-32710517

RESUMO

Herein, norbornyl (NB), a bulky annular nonconjugated spacer, is melded into π systems to construct two groups of ladder-type room-temperature phosphorescence (RTP) luminogens. The effect of the NB on π-π interactions, packing modes and RTP performance is explored systematically. The experimental and computational results demonstrate the versatility of NB in reducing π-π distances and synergistically intensifying the intermolecular interactions, which not only induces intersystem crossing from S1 to Tn but also diminishes the nonradiative decay of triplet excitons. Impressively, 1800-fold phosphorescence lifetime enhancement is achieved in comparison with the reference compounds without NB. The molecular packing and RTP performance can be further modulated by the length of the backbones and terminal end-groups. It is quite peculiar that NB-annulated phthalic acid exhibits reversible photochromism in the solid state, likely due to the formation of persistent radical pairs. Our study paves an ingenious avenue towards enhancing intermolecular interactions and provides significant implications for a better comprehensive understanding of the origin of their RTP and the inherent photophysical mechanism.

7.
Research (Wash D C) ; 2020: 8649102, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32190835

RESUMO

For the first time, electroplex emission is utilized to enhance the performance of nondoped blue organic light-emitting diodes (OLEDs). By decorating the twisted blue-emitting platform and adjusting the electronic structure, three molecules of 3Cz-Ph-CN, 3Cz-mPh-CN, and 3Ph-Cz-CN with a donor-acceptor structure are synthesized and investigated. When external voltage is applied, electroplex emission, which contributes to the emission performance of OLED, can be realized at the interface between the emitting layer and the electron-transporting layer. Accordingly, high external quantum efficiency of 18.1% can be achieved, while the emission wavelength of the device can be controlled in the blue region. Our results provide the possibility to enhance the performance of OLED through electroplex emission, in addition to the generally investigated thermally activated delayed fluorescence (TADF). Excitedly, when 3Ph-Cz-CN is used as host material in orange-emitting phosphorous OLEDs (PO-01 as the dopant), unprecedented high external quantum efficiency of 27.4% can also be achieved.

8.
J Phys Chem Lett ; 10(22): 7141-7147, 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31659902

RESUMO

Achieving efficient ultralong purely organic phosphorescent luminophores is still a big challenge due to the slow intersystem crossing (ISC) process. Herein, we present a facile molecular design strategy that incorporates a secondary group (Br atom or methoxy group) into o-BrCz that can significantly enhance the ISC rate constant (kISC) and achieve high phosphorescence quantum yields (ΦP). As a result, DBrCz and MeBrCz achieved a profound increase of kISC ≈ 108 s-1 and obtained excellent ΦP values up to 24.53 and 27.81% in solid powder, respectively. Given the highly efficient ΦP and proper τp, DBrCz and MeBrCz are applied to alternating current (AC) light-emitting diodes (LEDs), achieving a white LED with CIE coordinates (0.28, 0.29) and a CRI over 90. As a proof of concept, we demonstrate its compensation effect on the dark duration of AC-LED with a reduced percent flicker of 78%. This result extends a new potential application for RTP luminophores in the lighting field.

9.
Chemistry ; 25(28): 7031-7037, 2019 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-30882928

RESUMO

Organic luminescence with different forms continues to be one of the most active research fields in science and technology. Herein, an ultra-simple organic molecule (TPA-B), which exhibits both mechanoluminescence (ML) and photo-induced room-temperature phosphorescence (RTP) in the crystalline state, provides an opportunity to reveal the internal mechanism of ML and the dynamic process of photo-induced RTP in the same molecule. Through the detailed investigation of photophysical properties together with crystal structures, the key role of molecular packing and intermolecular interactions was highlighted in the luminescence response by mechanical and light stimulus, affording efficient strategies to design potential smart functional materials with multiple luminescence properties.

10.
Angew Chem Int Ed Engl ; 57(51): 16821-16826, 2018 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-30375137

RESUMO

Organic tribophosphorescence materials are rarely reported and the introduction of Br atoms may be a practical way to design such materials. Here four bromine-substituted fluorene-based derivatives are presented and BrFlu-CBr, having fluorescence-phosphorescence dual-emission induced not only by UV light but also by mechanical stimulus, manifests the highest phosphorescence efficiency of 4.56 % upon photoirradiation. During the grinding process, three different triboluminescent spectra were identified. Upon introduction of a mechanical stimulus, the triboluminescence emission is cyan, whereas after an extended period it changed to blue. After removing the mechanical stimulus, green-white phosphorescent emission was observed. Careful research on single-crystal structures and theoretical calculations demonstrate that strong Br⋅⋅⋅Br interactions are vital to facilitate spin-orbit coupling and promote intersystem crossing, thus generating the unique properties.

11.
ACS Nano ; 12(9): 9532-9540, 2018 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-30134104

RESUMO

The development of fluorogens with deep-red emission is one of the hottest topics of investigation in the field of bio/chemosensors and bioimaging. Herein, the tunable fluorescence of perylene diimide (PDI) derivatives was achieved by the incorporation of varied isolation groups linked on the PDI core. With the enlarged sizes of isolation groups, the conversion from aggregation caused quenching to aggregation-induced emission was obtained in their fluorescence variations from solutions to nanoparticles, as the result of the efficient inhibition of π-π stacking by the larger isolation groups. Accordingly, DCzPDI bearing 1,3-di(9H-carbazol-9-yl)benzene as the biggest isolation group exhibited the bright deep-red emission in the aggregated state with a quantum yield of 12.3%. Combined with the three-photon excited fluorescence microscopy (3PFM) technology, through-skull 3PFM imaging of mouse cerebral vasculature can be realized by DCzPDI nanoparticles with good biocompatibility, and the penetration depth can be as deep as 450 µm.


Assuntos
Derivados de Benzeno/química , Carbazóis/química , Corantes Fluorescentes/química , Imidas/química , Microscopia de Fluorescência por Excitação Multifotônica/métodos , Nanopartículas/química , Imagem Óptica/métodos , Perileno/análogos & derivados , Animais , Derivados de Benzeno/farmacocinética , Derivados de Benzeno/toxicidade , Vasos Sanguíneos/diagnóstico por imagem , Vasos Sanguíneos/metabolismo , Encéfalo/irrigação sanguínea , Encéfalo/diagnóstico por imagem , Carbazóis/farmacocinética , Carbazóis/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Corantes Fluorescentes/farmacocinética , Corantes Fluorescentes/toxicidade , Células HeLa , Humanos , Imidas/farmacocinética , Imidas/toxicidade , Camundongos , Perileno/química , Perileno/farmacocinética , Perileno/toxicidade , Distribuição Tecidual
12.
Sci Bull (Beijing) ; 63(2): 108-116, 2018 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36658922

RESUMO

Perylene diimide (PDI) derivatives, due to their special opto-electronic property, have been successfully utilized in organic field-effect transistor (OFET), solar cells, and as non-fullerene acceptor and others, while few cases in organic light-emitting diodes (OLEDs). In this work, six perylene bisimide-based red emitters, N,N'-bis(2-decyltetradecyl)-1-([1,1':3',1″-terphenyl]-5'-yl)perylene-3,4,9,10-diimide (STPH), N,N'-bis(2-decyltetradecyl)-1,7-bis([1,1':3',1″-terphenyl]-5'-yl)perylene-3,4,9,10-diimide (DTPH), N,N'-bis(2-decyltetradecyl)-1-(5'-phenyl-[1,1':3',1″-terphenyl]-4-yl)perylene-3,4,9,10-diimide (STRPH), N,N'-bis(2-decyltetradecyl)-1,7-bis(5'-phenyl-[1,1':3',1″-terphenyl]-4-yl)perylene-3,4,9,10-diimide (DTRPH), N,N'-bis(2-decyltetradecyl)-1-(4-(2,2-diphenylvinyl)phenyl)perylene-3,4,9,10-diimide (STTPE) and N,N'-bis(2-decyltetradecyl)-1,7-bis(4-(2,2-diphenylvinyl)phenyl)perylene-3,4,9,10-diimide (DTTPE), with the excellent chemical, thermal and photo-chemical stability, are synthesized through the convenient Suzuki coupling reaction, in which, the fluorescent properties can be modified easily from ACQ to AIE by just simply changing the bulky volume of the introduced aromatic substituents. After being fabricated into organic light-emitting diodes, STRPH exhibits the best performance with the maximum luminescence, power efficiency, current efficiency and external quantum efficiency of 1,948 cd m-2, 2.04 lm W-1, 5.85 cd A-1, 4.93% at Commission Internationale de L'Eclairage (CIE) coordinates of (0.56, 0.34), as the result of the high efficient energy transfer and good energy match achieved in the device.

13.
Angew Chem Int Ed Engl ; 56(48): 15299-15303, 2017 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-28981197

RESUMO

Two stable, purely organic luminogens exhibit both mechano- (ML) and photoluminescence (PL) with dual fluorescence-phosphorescence emissions at room temperature. Careful analysis of the crystal structures, coupled with theoretical calculations, demonstrate that room-temperature phosphorescence and ML properties are strongly related to molecular packing. In particular, the formation and fracture of molecular dimers with intermolecular charge-transfer properties has a significant effect on intersystem crossing, as well as excited triplet state emissions, in both PL and ML processes.

14.
Biomed Res Int ; 2017: 8176089, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28133612

RESUMO

Tang-luo-ning (TLN) is a traditional Chinese herbal recipe for treating diabetic peripheral neuropathy (DPN). In this study, we investigated mitochondrial protein profiles in a diabetic rat model and explored the potential protective effect of TLN. Diabetic rats were established by injection of streptozocin (STZ) and divided into model, alpha lipoic acid (ALA), and TLN groups. Mitochondrial proteins were isolated from dorsal root ganglia and proteomic analysis was used to quantify the differentially expressed proteins. Tang-luo-ning mitigated STZ-induced diabetic symptoms and blood glucose level, including response time to cold or hot stimulation and nerve conductive velocity. As compared to the normal, there were 388 differentially expressed proteins in the TLN group, 445 in ALA group, and 451 in model group. As compared to the model group, there were 275 differential proteins in TLN group and 251 in ALA group. As compared to model group, mitochondrial complex III was significantly decreased, while glutathione peroxidase and peroxidase were increased in TLN group. When compared with ALA group, the mitochondrial complex III was increased, and mitochondrial complex IV was decreased in TLN group. Together, TLN should have a strong antioxidative activity, which appears to be modulated through regulation of respiratory complexes and antioxidases.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Medicamentos de Ervas Chinesas/uso terapêutico , Gânglios Espinais/enzimologia , Mitocôndrias/enzimologia , Oxirredutases/metabolismo , Proteômica/métodos , Animais , Glicemia/metabolismo , Cromatografia por Troca Iônica , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/fisiopatologia , Modelos Animais de Doenças , Medicamentos de Ervas Chinesas/farmacologia , Gânglios Espinais/efeitos dos fármacos , Hemoglobinas Glicadas/metabolismo , Masculino , Espectrometria de Massas , Mitocôndrias/efeitos dos fármacos , Proteínas Mitocondriais/metabolismo , Condução Nervosa/efeitos dos fármacos , Peptídeos/metabolismo , Ratos Sprague-Dawley , Estreptozocina , Ácido Tióctico/farmacologia , Ácido Tióctico/uso terapêutico
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