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1.
Adv Mater ; : e2402708, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38837440

RESUMEN

Emerging intrinsically flexible fully π-conjugated polymers (FπCPs) are a promising functional material for flexible optoelectronics, attributed to their potential interchain interpenetration and entanglement. However, the challenge remains in obtaining elastic-plastic FπCPs with intrinsic robust optoelectronic property and excellent long-term and cycling deformation stability simultaneously for applications in deep-blue flexible polymer light-emitting diodes (PLEDs). This study, demonstrates a series of elastic-plastic FπCPs (P1-P4) with an excellent energy dissipation capacity via side-chain internal plasticization for the ultra-deep-blue flexible PLEDs. First, the freestanding P1 film exhibited a maximum fracture strain of 34.6%. More interestingly, the elastic behavior is observed with a low strain (≤10%), and the stretched film with a high deformation (>10%) attributed to plastic processing revealed the robust capacity to realize energy absorption and release. The elastic-plastic P1 film exhibits outstanding ultra-deep-blue emission, with an efficiency of 56.38%. Subsequently, efficient PLEDs are fabricated with an ultra-deep-blue emission of CIE (0.16, 0.04) and a maximum external quantum efficiency of 1.73%. Finally, stable and efficient ultra-deep-blue electroluminescence are obtained from PLEDs based on stretchable films with different strains and cycling deformations, suggesting excellent elastic-plastic behavior and deformation stability for flexible electronics.

2.
Adv Mater ; 36(19): e2307605, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38349697

RESUMEN

Emerging printed large-area polymer light-emitting diodes (PLEDs) are essential for manufacturing flat-panel displays and solid lighting devices. However, it is challenging to obtain large-area and stable ultradeep-blue PLEDs because of the lack of light-emitting conjugated polymers (LCPs) with robust deep-blue emissions, excellent morphological stabilities, and high charging abilities. Here, a novel unsymmetrically substituted polydiarylfluorene (POPSAF) is obtained with stable narrowband emission for large-area printed displays via triphenylamine (TPA) spirofunctionalization of LCPs. POPSAF films show narrowband and stable ultradeep-blue emission with a full width at half maximum (FWHM) of 36 nm, associated with their intrachain excitonic behavior without obvious polaron formation. Compared to controlled poly[4-(octyloxy)-9,9-diphenylfluoren-2,7-diyl]-co-[5-(octyloxy)-9,9-diphenylfluoren-2,7-diyl] (PODPF), excellent charge transport is observed in the POPSAF films because of the intrinsic hole transport ability of the TPA units. Large-area PLEDs are fabricated via blade-coating with an emission area of 9 cm2, which exhibit uniform ultradeep-blue emission with an FWHM of 36 nm and corresponding Commission internationale de l'éclairage (CIE) coordinates of (0.155, 0.072). These findings are attributed to the synergistic effects of robust emission, stable morphology, and printing capacity. Finally, preliminary printed passive matrix (PM) PLED displays with 20 × 20 pixels monochromes are fabricated, confirmed the effectiveness of spirofunctionalization in optoelectronics.

3.
JMIR Form Res ; 7: e42297, 2023 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-37079346

RESUMEN

BACKGROUND: Online medical and health communities provide a platform for internet users to share experiences and ask questions about medical and health issues. However, there are problems in these communities, such as the low accuracy of the classification of users' questions and the uneven health literacy of users, which affect the accuracy of user retrieval and the professionalism of the medical personnel answering the question. In this context, it is essential to study more effective classification methods of users' information needs. OBJECTIVE: Most online medical and health communities tend to provide only disease-type labels, which do not give a comprehensive summary of users' needs. The study aims to construct a multilevel classification framework based on the graph convolutional network (GCN) model for users' needs in online medical and health communities so that users can perform more targeted information retrieval. METHODS: Using the Chinese online medical and health community "Qiuyi" as an example, we crawled questions posted by users in the "Cardiovascular Disease" section as the data source. First, the disease types involved in the problem data were segmented by manual coding to generate the first-level label. Second, the needs were identified by K-means clustering to generate the users' information needs label as the second-level label. Finally, by constructing a GCN model, users' questions were automatically classified, thus realizing the multilevel classification of users' needs. RESULTS: Based on the empirical research of questions posted by users in the "Cardiovascular Disease" section of Qiuyi, the hierarchical classification of users' questions (data) was realized. The classification models designed in the study achieved accuracy, precision, recall, and F1-score of 0.6265, 0.6328, 0.5788, and 0.5912, respectively. Compared with the traditional machine learning method naïve Bayes and the deep learning method hierarchical text classification convolutional neural network, our classification model showed better performance. At the same time, we also performed a single-level classification experiment on users' needs, which in comparison with the multilevel classification model exhibited a great improvement. CONCLUSIONS: A multilevel classification framework has been designed based on the GCN model. The results demonstrated that the method is effective in classifying users' information needs in online medical and health communities. At the same time, users with different diseases have different directions for information needs, which plays an important role in providing diversified and targeted services to the online medical and health community. Our method is also applicable to other similar disease classifications.

4.
Nanomaterials (Basel) ; 13(12)2023 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-37368245

RESUMEN

We have demonstrated a two-step wet chemical approach for synthesizing ternary Ag/Ag2S/CdS heterostructures for efficient photocatalytic hydrogen evolution. The CdS precursor concentrations and reaction temperatures are crucial in determining the efficiency of photocatalytic water splitting under visible light excitation. In addition, the effect of operational parameters (such as the pH value, sacrificial reagents, reusability, water bases, and light sources) on the photocatalytic hydrogen production of Ag/Ag2S/CdS heterostructures was investigated. As a result, Ag/Ag2S/CdS heterostructures exhibited a 3.1-fold enhancement in photocatalytic activities compared to bare CdS nanoparticles. Furthermore, the combination of Ag, Ag2S, and CdS can significantly enhance light absorption and facilitate the separation and transport of photogenerated carriers through the surface plasma resonance (SPR) effect. Furthermore, the Ag/Ag2S/CdS heterostructures in seawater exhibited a pH value approximately 2.09 times higher than in de-ionized water without an adjusted pH value under visible light excitation. The ternary Ag/Ag2S/CdS heterostructures provide new potential for designing efficient and stable photocatalysts for photocatalytic hydrogen evolution.

5.
J Virol ; 85(7): 3517-25, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21228234

RESUMEN

High temperature (32 to 33°C) has been shown to reduce mortality in white spot syndrome virus (WSSV)-infected shrimps, but the mechanism still remains unclear. Here we show that in WSSV-infected shrimps cultured at 32°C, transcriptional levels of representative immediate-early, early, and late genes were initially higher than those at 25°C. However, neither the IE1 nor VP28 protein was detected at 32°C, suggesting that high temperature might inhibit WSSV protein synthesis. Two-dimensional gel electrophoresis analysis revealed two proteins, NAD-dependent aldehyde dehydrogenase (ALDH) and the proteasome alpha 4 subunit (proteasome α4), that were markedly upregulated in WSSV-infected shrimps at 32°C. Reverse transcription-PCR (RT-PCR) analysis of members of the heat shock protein family also showed that hsp70 was upregulated at 32°C. When aldh, proteasome α4, and hsp70 were knocked down by double-stranded RNA interference and shrimps were challenged with WSSV, the aldh and hsp70 knockdown shrimps became severely infected at 32°C, while the proteasome α4 knockdown shrimps remained uninfected. Our results therefore suggest that ALDH and Hsp70 both play an important role in the inhibition of WSSV replication at high temperature.


Asunto(s)
Aldehído Deshidrogenasa/metabolismo , Proteínas HSP70 de Choque Térmico/metabolismo , Penaeidae/virología , Temperatura , Replicación Viral/efectos de la radiación , Virus del Síndrome de la Mancha Blanca 1/fisiología , Virus del Síndrome de la Mancha Blanca 1/efectos de la radiación , Animales , Electroforesis en Gel Bidimensional , Perfilación de la Expresión Génica , Técnicas de Silenciamiento del Gen , Complejo de la Endopetidasa Proteasomal/metabolismo , Subunidades de Proteína/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Proteínas Virales/metabolismo
6.
Nanomaterials (Basel) ; 12(22)2022 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-36432278

RESUMEN

This study used a rapid and simple microwave-assisted synthesis method to grow ZnO nanoneedle arrays on the silicon substrate with the ZnO seed layer. The effects of reaction temperature and time on the lengths of ZnO nanoneedle arrays were investigated. The appropriate temperature programming step can grow the longer ZnO nanoneedle arrays at the same reaction time (25 min), which is 2.08 times higher than without the temperature programming step. The geometry of the ZnO nanoneedle arrays features a gradual decrease from the Si substrate to the surface, which provides an excellent progressive refractive index between Si and air, resulting in excellent antireflection properties over an extensive wavelength range. In addition, the ZnO nanoneedle arrays exhibit a suitable structure for uniform deposition of Ag nanoparticles, which can provide three-dimensional hot spots and surface active sites, resulting in higher surface-enhanced Raman scattering (SERS) enhancement, high uniformity, high reusability, and low detection limit for R6G molecule. The ZnO/Ag nanoneedle arrays can also reveal a superior SERS-active substrate detecting amoxicillin (10-8 M). These results are promising for applying the SERS technique for rapid low-concentration determination in different fields.

7.
Materials (Basel) ; 15(24)2022 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-36556814

RESUMEN

ZnO nanowires and nanowalls can be fabricated on the glass substrate with a ZnO seed film and low-cost aluminum (Al) foil by the aqueous solution method (ASM), respectively. The different concentrations of ZnO precursors can use to control the densities of ZnO nanowalls. In addition, FESEM, FETEM, EDS, XRD, XPS, and CL were used to evaluate the characteristics of ZnO nanowalls. The ZnO nanowalls exhibited higher photocatalytic efficiency (99.4%) than that of ZnO nanowires (53.3%) for methylene blue (MB) degradation under UVC light irradiation at the ZnO precursors of 50 mM. This result is attributed to ZnO nanowalls with Al-doped, which can improve the separation of photogenerated electron-hole pairs for enhanced photocatalytic activity. In addition, ZnO nanowalls can also reveal higher photocatalytic activity for the degradation of tetracycline capsules (TC) rather than commercial ZnO nanopowder under UVC light irradiation. The superoxide and hydroxyl radicals play essential roles in the degradation of MB and TC solutions by the radical-trapping experiment. Furthermore, the ZnO nanowalls exhibit excellent recycling and reuse capacity for up to four cycles for the degradation of MB and TC. This study highlights the potential use of ZnO nanowalls directly grown on commercial and low-cost Al foil as noble metal-free photocatalysis.

8.
Stem Cell Res Ther ; 12(1): 508, 2021 09 22.
Artículo en Inglés | MEDLINE | ID: mdl-34551822

RESUMEN

BACKGROUND: The c.G6055A (p.G2019S) mutation in leucine-rich repeat kinase 2 (LRRK2) is the most prevalent genetic cause of Parkinson's disease (PD). CRISPR/Cas9-mediated genome editing by homology-directed repair (HDR) has been applied to correct the mutation but may create small insertions and deletions (indels) due to double-strand DNA breaks. Adenine base editors (ABEs) could convert targeted A·T to G·C in genomic DNA without double-strand breaks. However, the correction efficiency of ABE in LRRK2 c.G6055A (p.G2019S) mutation remains unknown yet. This study aimed to compare the mutation correction efficiencies and off-target effects between HDR and ABEs in induced pluripotent stem cells (iPSCs) carrying LRRK2 c.G6055A (p.G2019S) mutation. METHODS: A set of mutation-corrected isogenic lines by editing the LRRK2 c.G6055A (p.G2019S) mutation in a PD patient-derived iPSC line using HDR or ABE were established. The mutation correction efficacies, off-target effects, and indels between HDR and ABE were compared. Comparative transcriptomic and proteomic analyses between the LRRK2 p.G2019S iPSCs and isogenic control cells were performed to identify novel molecular targets involved in LRRK2-parkinsonism pathways. RESULTS: ABE had a higher correction rate (13/53 clones, 24.5%) than HDR (3/47 clones, 6.4%). Twenty-seven HDR clones (57.4%), but no ABE clones, had deletions, though 14 ABE clones (26.4%) had off-target mutations. The corrected isogenic iPSC-derived dopaminergic neurons exhibited reduced LRRK2 kinase activity, decreased phospho-α-synuclein expression, and mitigated neurite shrinkage and apoptosis. Comparative transcriptomic and proteomic analysis identified different gene expression patterns in energy metabolism, protein degradation, and peroxisome proliferator-activated receptor pathways between the mutant and isogenic control cells. CONCLUSIONS: The results of this study envision that ABE could directly correct the pathogenic mutation in iPSCs for reversing disease-related phenotypes in neuropathology and exploring novel pathophysiological targets in PD.


Asunto(s)
Células Madre Pluripotentes Inducidas , Enfermedad de Parkinson , Neuronas Dopaminérgicas , Edición Génica , Humanos , Proteína 2 Quinasa Serina-Treonina Rica en Repeticiones de Leucina/genética , Mutación , Enfermedad de Parkinson/genética , Enfermedad de Parkinson/terapia , Fenotipo , Proteómica
9.
Dev Comp Immunol ; 34(10): 1068-74, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20546774

RESUMEN

AAP-1 (WSSV449), an anti-apoptosis protein encoded by white spot syndrome virus (WSSV), blocked apoptosis in insect cells (SF9) induced by Penaeus monodon effector caspase (Pm caspase). Here, to characterize in detail the anti-Pm caspase activity of AAP-1, both proteins were expressed and purified from Escherichia coli and their interactions were assayed in vitro. We found that although AAP-1 could inhibit Pm caspase activity, the inhibition was not as efficient as that of baculovirus anti-apoptosis protein P35. We further confirmed the binding and cleavage of AAP-1 by Pm caspase, and detected three AAP-1 cleavage products. Mutational analysis and protein N-terminal sequencing revealed that whereas both Asp233 and Asp272 residues of AAP-1 are involved in binding and cleavage by Pm caspase, only the Asp272 is involved in Pm caspase inhibition. Asp233, on the other hand, negatively regulates AAP-1's anti-Pm caspase activity. Lastly, AAP-1 homotypically interacts with each other both in vitro and in insect cells.


Asunto(s)
Proteínas Reguladoras de la Apoptosis/metabolismo , Caspasas Efectoras/metabolismo , Infecciones por Virus ADN/metabolismo , Pandalidae , Proteínas Reguladoras y Accesorias Virales/metabolismo , Virus del Síndrome de la Mancha Blanca 1/fisiología , Animales , Apoptosis/genética , Proteínas Reguladoras de la Apoptosis/genética , Baculoviridae , Línea Celular , Análisis Mutacional de ADN , Infecciones por Virus ADN/genética , Infecciones por Virus ADN/inmunología , Infecciones por Virus ADN/virología , Represión Enzimática , Insectos , Unión Proteica , Proteínas Virales/metabolismo , Proteínas Reguladoras y Accesorias Virales/genética , Virus del Síndrome de la Mancha Blanca 1/patogenicidad
10.
Ai Zheng ; 23(10): 1210-2, 2004 Oct.
Artículo en Zh | MEDLINE | ID: mdl-15473938

RESUMEN

BACKGROUND & OBJECTIVE: It is difficult to diagnose tumor residue by CT/MRI after treatment. The application of (18)F-fluorodeoxyglucose positron emission tomography ((18)F-FDG PET) to determine the suspected tumor residue after treatment has become a hot target in the study of radiotherapy. This study was designed to discuss the clinical value of (18)-FDG PET imaging in post-operative and post-radiotherapeutic intracranial glioma. METHODS: (18)F-FDG PET imaging was performed in 23 patients with post-operative and post-radio-therapeutic intracranial glioma, and compared with CT/MRI. The final diagnosis of tumor residue was proved by pathology or clinical follow-up. RESULTS: Of 23 patients, 12 showed (18)F-FDG PET positive, and 11 showed negative,among which 3 were false negative. The accuracy of (18)F-FDG PET was 87.0% (20/23), significantly higher than 60.9% (14/23) of CT/MRI scan (P< 0.05). The diagnosis of tumor residue in 9 patients cannot be determined by CT/MRI, while 4 of these patients showed (18)F-FDG PET positive, and the other 5 showed (18)F-FDG PET negative. Eight of 23 patients diagnosed tumor residues by CT/MRI, showed (18)F-FDG PET positive,too. Six patients,diagnosed by CT/MRI as radioactive-disease sufferers, and PET indicated with low or deficient FDG metabolism, were proved to have radioactive diseases by follow-up. CONCLUSIONS: (18)F-FDG PET imaging has significant dominance in characterizing lesions,and differentiating tumor residue in post-operative and post-radiotherapeutic intracranial glioma. Combined with CT and MRI, it can provide both anatomical and functional information for treatment.


Asunto(s)
Neoplasias Encefálicas/diagnóstico por imagen , Fluorodesoxiglucosa F18 , Glioma/diagnóstico por imagen , Neoplasia Residual/diagnóstico por imagen , Radiofármacos , Adulto , Astrocitoma/diagnóstico por imagen , Astrocitoma/radioterapia , Astrocitoma/cirugía , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/cirugía , Femenino , Glioma/radioterapia , Glioma/cirugía , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Tomografía de Emisión de Positrones , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
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