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1.
Opt Lett ; 48(8): 2054-2057, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-37058640

RESUMO

The dynamic control of magnetization by short laser pulses has recently attracted interest. The transient magnetization at the metallic magnetic interface has been investigated through second-harmonic generation and the time-resolved magneto-optical effect. However, the ultrafast light-driven magneto-optical nonlinearity in ferromagnetic heterostructures for terahertz (THz) radiation remains unclear. Here, we present THz generation from a metallic heterostructure, Pt/CoFeB/Ta, which is ascribed to an ∼6-8% contribution from the magnetization-induced optical rectification and an ∼94-92% contribution from both spin-to-charge current conversion and ultrafast demagnetization. Our results show that THz-emission spectroscopy is a powerful tool to study the picosecond-time-scale nonlinear magneto-optical effect in ferromagnetic heterostructures.

2.
Int J Cancer ; 151(1): 128-137, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35188268

RESUMO

Optimal treatment for resectable esophageal squamous cell carcinoma (ESCC) is controversial, especially in the context of potential benefit of combining PD-1 blockade with neoadjuvant therapy. This phase 2 study aimed to assess neoadjuvant camrelizumab plus chemotherapy in this population. Patients (clinical stage II-IVA) received two cycles of neoadjuvant chemoimmunotherapy (NIC) with camrelizumab (200 mg on day 1) plus nab-paclitaxel (260 mg/m2 in total on day 1 and day 8) and cisplatin (75 mg/m2 in total on days 1-3) of each 21-day cycle. Surgery was performed approximately 6 weeks after completion of NIC. Primary endpoint was complete pathologic response (CPR) rate in primary tumor. Secondary endpoints were objective response rate (ORR) per RECIST v1.1, 2-year progression-free survival (PFS) rate after surgery, PFS, overall survival (OS) and safety during NIC and perioperative period. Between 17 January 2020 and 8 December 2020, 56 patients were enrolled, and 51 received esophagectomy. Data cutoff date was 25 August 2021. The CPR rate was 35.3% (95% CI, 21.7%-48.9%). NIC had an ORR of 66.7% (95% CI, 40.0%-70.4%) and treatment-related adverse events (TRAEs) of low severity (grade 1-2, 75.0%; grade 3, 10.7%; grade 4-5, no). No perioperative mortality occurred. Three (5.9%) patients had tumor recurrence and one (2.0%) patient died. The 2-year PFS rate, median PFS and median OS had not been reached yet. Camrelizumab plus neoadjuvant chemotherapy in resectable ESCC demonstrates promising efficacy with acceptable toxicity, providing a feasible and effective option. Study is ongoing for long-term survival analyses.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Anticorpos Monoclonais Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Cisplatino/uso terapêutico , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/tratamento farmacológico , Carcinoma de Células Escamosas do Esôfago/patologia , Humanos , Terapia Neoadjuvante/efeitos adversos , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/etiologia
3.
J Cell Mol Med ; 24(18): 10501-10511, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32705806

RESUMO

Andrographolide (Andro), a component from Chinese medicinal herb Andrographis paniculata, could alleviate pulmonary fibrosis in rodents. Yet, whether and how Andro mitigates epithelial-mesenchymal transition (EMT) induced by TGF-ß1 remain unknown. This study aimed to explore the effect of Andro on TGF-ß1-induced EMT in human alveolar epithelial cells (AECs) and the mechanisms involved. We illustrated that Andro inhibited TGF-ß1-induced EMT and EMT-related transcription factors in alveolar epithelial A549 cells. Andro also reduced TGF-ß1-induced cell migration and synthesis of pro-fibrotic factors (ie CCN-2, TGF-ß1), matrix metalloproteinases (ie MMP-2, MMP-9) and extracellular matrix (ECM) components (ie collagen 1), implying the inhibiting effect of Andro on TGF-ß1-induced EMT-like cell behaviours. Mechanistically, Andro treatment not only repressed TGF-ß1-induced Smad2/3 phosphorylation and Smad4 nuclear translocation, but also suppressed TGF-ß1-induced Erk1/2 phosphorylation and nuclear translocation in A549 cells. And treatment with ALK5 inhibitor (SB431542) or Erk1/2 inhibitors (SCH772984 and PD98059) remarkably reduced EMT evoked by TGF-ß1. In addition, Andro also reduced TGF-ß1-induced intracellular ROS generation and NOX4 expression, and elevated antioxidant superoxide dismutase 2 (SOD2) expression, demonstrating the inhibiting effect of Andro on TGF-ß1-induced oxidative stress, which is closely linked to EMT. Furthermore, Andro remarkably attenuated TGF-ß1-induced down-regulation of sirtuin1 (Sirt1) and forkhead box O3 (FOXO3), implying that Andro protects AECs from EMT partially by activating Sirt1/FOXO3-mediated anti-oxidative stress pathway. In conclusion, Andro represses TGF-ß1-induced EMT in AECs by suppressing Smad2/3 and Erk1/2 signalling pathways and is also closely linked to the activation of sirt1/FOXO3-mediated anti-oxidative stress pathway.


Assuntos
Células Epiteliais Alveolares/metabolismo , Diterpenos/farmacologia , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Fator de Crescimento Transformador beta1/farmacologia , Células A549 , Células Epiteliais Alveolares/efeitos dos fármacos , Antioxidantes/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Diterpenos/química , Regulação para Baixo/efeitos dos fármacos , Proteína Forkhead Box O3/metabolismo , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Oxidantes/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sirtuína 1/metabolismo , Proteínas Smad/metabolismo , Fatores de Transcrição/metabolismo
4.
Nanotechnology ; 31(47): 475404, 2020 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-32886645

RESUMO

Fe/N/C catalysts have been regarded as prospective electrocatalysts for oxygen reduction reactions (ORR). As reported, doping S into the Fe/N/C catalyst is an effective strategy to further enhance its ORR performance. Herein, a rational design is demonstrated to synthesize Fe/S/N/C catalysts with a flexible ratio of the doped Fe and S. Through atomic substitution and molecular confinement methods, Fe and S were incorporated into the ZIF-8 precursor, respectively. After further pyrolysis, the Fe/S/N/C catalyst was obtained with uniformly dispersed Fe-Nx, C-S-C active sites and high specific surface area. The Fe/S/N/C catalyst shows a high half-wave potential in alkaline medium, nearly 32 mV higher than the commercial Pt/C, owing to the strong synergistic effect from Fe-Nx and C-S-C active sites. Additionally, the Fe/S/N/C catalyst exhibits good long-term electrocatalytic durability and high endurance to methanol crossover, implying it is a suitable candidate to take the place of conventional Pt or Pt-based catalysts in electrochemical devices.

5.
J Sep Sci ; 43(2): 462-469, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31630474

RESUMO

Two proposed syringe membrane filter solid phase microextraction and syringe membrane filter liquid/solid phase microextraction, coupled separately with high performance liquid chromatography, were developed for simultaneous enrichment and determination of the trace level of flavonoids in traditional Chinese medicine. In syringe membrane filter solid phase microextraction, the membrane of syringe membrane filter was served as a solid adsorption film to adsorb target analytes. And in syringe membrane filter liquid/solid phase microextraction, the membrane of syringe membrane filter was used as not only an adsorption phase, but also as a holder of extraction solvent to realize liquid-solid synergistic extraction. The simple operation, rapid extraction, and little or no organic solvent consumption make the two approaches very interesting. To evaluate the two proposed approaches, the crucial parameters affecting the enrichment factors of target analytes were investigated and optimized, and the two microextractions were intercompared. Moreover, their microextraction mechanisms were analyzed and described. Under the optimized conditions, both the new approaches achieved good linearities, accuracies, precisions, and low limits of detection, and the two methods were successfully applied for concentration of the flavonoids in traditional Chinese medicines.


Assuntos
Flavonoides/análise , Microextração em Fase Líquida , Microextração em Fase Sólida , Seringas , Cromatografia Líquida de Alta Pressão , Microextração em Fase Líquida/instrumentação , Medicina Tradicional Chinesa , Estrutura Molecular , Microextração em Fase Sólida/instrumentação
6.
Small ; 15(15): e1900354, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30861634

RESUMO

Interfacial solar vapor generation is considered to be an efficient and eco-friendly technology for harvesting solar energy and providing freshwater. However, the efficient and long-term steady evaporation of seawater under 1 sun becomes a critical issue when it comes to practical applications. Based on this issue, a special double-layer structure, which contains a metal-organic-framework-derived hierarchical porous carbon membrane (HPCM) for solar absorption and a polystyrene sulfonate (PSS)@Cu3 (BTC)3 •3H2 O (HKUST-1)/single-walled carbon nanotube (SWCNT) (PHS) membrane for water supply and salt blocking, is designed in this work. The converted heat is utilized efficiently in situ to drive the evaporation of water-trapped HPCM. The PHS membrane with PSS modified channels successfully prevents the deposition of salt. Due to the synergistic combination of the HPCM and PHS membranes, the device exhibits a remarkably high water evaporation rate of 1.38 kg m-2 h-1 and solar-vapor generation efficiency of 90.8% under 1 sun.

7.
Analyst ; 144(12): 3892-3897, 2019 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-31120053

RESUMO

Mercury, as one of the most prevalent toxic metals released by various natural and anthropogenic processes, causes severe pollution of soil and groundwater. In this work, R-phycoerythrin (R-PE) proteins encapsulated into ZIF-8 composite thin films were prepared via a solid-confinement conversion process and applied as fluorescent sensors for mercury ion detection. The R-PE proteins encapsulated into ZIF-8 exhibit dual color emissions including green (518 nm) and red (602, 650 nm) fluorescence, while the original orange emission (578 nm) of pure R-PE is significantly suppressed. R-PE@ZIF-8 presents excellent selectivity and sensitivity for mercury detection in a large pH range without buffer solution. Under the optimal conditions, there is a good linear relationship between the fluorescence quenching efficiencies of R-PE@ZIF-8 and logarithmic concentrations of mercury ions in the range of 0.001-50 µM with the detection limit (LOD) of 6.7 nM much lower than the guideline value given by the World Health Organization. Furthermore, multi-peak detection of R-PE@ZIF-8 improves the detection accuracy of Hg2+ concentration.


Assuntos
Mercúrio/análise , Estruturas Metalorgânicas/química , Ficoeritrina/química , Fluorescência , Hidróxidos/química , Limite de Detecção , Membranas Artificiais , Porphyra/química , Espectrometria de Fluorescência/métodos , Compostos de Zinco/química
8.
J Sep Sci ; 42(13): 2231-2238, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31021051

RESUMO

This study proposed a new ballpoint connector-protected salt-oil-salt liquid phase microextraction for extraction and enrichment of trace rhein and chrysophanol in rhubarb prior to determination of the analytes by high performance liquid chromatography. In this study, a handy ballpoint connector (between ballpoint tip and ink chamber) was used as extraction device, in which its cavity was filled with n-octanol, and the bare n-octanol in its two opening ends was covered with a thin layer of sodium chloride film. The design subtly assembled salt film onto ballpoint connector for extraction and enrichment, which greatly improved the enrichment factors of the target analytes. Moreover, the novel procedure and its extraction mechanism were described and analyzed, and several crucial parameters reflecting the extraction effect were investigated and optimized. Under optimum conditions, high enrichment factors (247 and 127), good linearities with r ≥ 0.9998, limits of detection (0.6-1.1 ng/mL), relative standard deviations of intra- and interday (2.2-8.8% and 4.3-8.9%), and average recoveries (97.6-98.1%), were obtained, respectively. The proposed method can not only eliminate the negative effects from viscosity and ion strength at high salt concentration of sample phase, but also make salting-out effect be focused on small area so as to maximize the extraction effect.


Assuntos
Antraquinonas/análise , Microextração em Fase Líquida , Óleos/química , Rheum/química , Cloreto de Sódio/química , Cromatografia Líquida de Alta Pressão
9.
IEEE Trans Biomed Eng ; PP2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38470574

RESUMO

Some classification studies of brain-computer interface (BCI) based on speech imagery show potential for improving communication skills in patients with amyotrophic lateral sclerosis (ALS). However, current research on speech imagery is limited in scope and primarily focuses on vowels or a few selected words. In this paper, we propose a complete research scheme for multi-character classification based on EEG signals derived from speech imagery. Firstly, we record 31 speech imagery contents, including 26 alphabets and 5 commonly used punctuation marks, from seven subjects using a 32-channel electroencephalogram (EEG) device. Secondly, we introduce the wavelet scattering transform (WST), which shares a structural resemblance to Convolutional Neural Networks (CNNs), for feature extraction. The WST is a knowledge-driven technique that preserves high-frequency information and maintains the deformation stability of EEG signals. To reduce the dimensionality of wavelet scattering coefficient features, we employ Kernel Principal Component Analysis (KPCA). Finally, the reduced features are fed into an Extreme Gradient Boosting (XGBoost) classifier within a multi-classification framework. The XGBoost classifier is optimized through hyperparameter tuning using grid search and 10-fold cross-validation, resulting in an average accuracy of 78.73% for the multi-character classification task. We utilize t-Distributed Stochastic Neighbor Embedding (t-SNE) technology to visualize the low-dimensional representation of multi-character speech imagery. This visualization effectively enables us to observe the clustering of similar characters. The experimental results demonstrate the effectiveness of our proposed multi-character classification scheme. Furthermore, our classification categories and accuracy exceed those reported in existing research.

10.
Int J Numer Method Biomed Eng ; 39(3): e3682, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36625630

RESUMO

The biomechanical stimulus is the most important factor for fracture healing and mainly determined by the structural stiffness of bone plate. Currently, the materials commonly used in bone plates are stainless steel and titanium, which often lead to stress shielding effects because of their higher elastic modulus compared with the bone. This article suggests an optimal design method of lattice bone plate based on fracture healing theory. First, the mechanical regulation model with deviatoric strain is established to simulate the tissue differentiation process during fracture healing process. The ratio of the average elastic modulus of callus at the 120th day to the elastic modulus of mature bone is used to characterize the fracture healing rate. Second, the optimal elastic modulus of the design domain is obtained by the optimization mathematical model with the maximum fracture healing rate. Then, the design domain is filled with microstructures, the porosity of which is adjusted to make it possible that the equivalent elastic modulus is equal to the optimized value. And the finite element analysis of the bone plate with microstructure is executed. Finally, the designed lattice bone plates are manufactured through 3D printing, and the mechanical test is carried out. The simulation results indicate that the fracture healing rate is maximum when the elastic modulus of material in design domain is 38 GPa under the constraints of fixation stability. And both the finite element analysis and experiment results show that the designed lattice bone plate meet the strength requirements of fracture internal fixation implants.


Assuntos
Consolidação da Fratura , Fraturas Ósseas , Humanos , Consolidação da Fratura/fisiologia , Placas Ósseas , Fixação Interna de Fraturas/métodos , Módulo de Elasticidade , Fenômenos Biomecânicos , Análise de Elementos Finitos , Estresse Mecânico
11.
Sci Rep ; 13(1): 11140, 2023 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-37429969

RESUMO

Exercise has profound but variable effects on the immune system. However, only limited information exists about the changes of exercise-induced gene expression in whole immune cells. The aim of this study is to unravel the potential molecular changes of genes which are related to immunity after exercise. The raw expression data and corresponding clinical of GSE18966 were downloaded from Gene Expression Omnibus database. The differentially expressed genes between control group and treat groups were performed by in-house developed perl scripts. A total of 83 differentially expressed genes (DEGs) (|log2 FC|> 1, FDR < 0.05) were identified between control and treat group 1 (0 h after exercise), 128 DEGs (|log2 FC|> 1, FDR < 0.05) between control and treat group 2 (4 h after exercise), and there was no significant difference between control and treat group 3 (20 h after exercise). Next, we identified 51 overlapping genes between treat group 1 (0 h after exercise) and treat group 2 (4 h after exercise) using Venn analysis. Protein-protein interaction (PPI) network was constructed by Cytoscape 3.7.2, and nine hub genes (S100A12, FCGR3B, FPR1, VNN2, AQP9, MMP9, OSM, NCF4, HP) were identified. Finally, 9 hub genes were identified as the potential biomarkers of exercise using validation set (GSE83578) verification analysis. These hub genes might serve as potential molecular targets of monitoring exercise and training processes in the further.


Assuntos
Perfilação da Expressão Gênica , Transcriptoma , Humanos , Leucócitos , Homologia de Genes , Bases de Dados Factuais
12.
Neuroscience ; 509: 103-112, 2023 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-36460220

RESUMO

Reconstructing visual stimulus images from the brain activity signals is an important research task in the field of brain decoding. Many methods of reconstructing visual stimulus images mainly focus on how to use deep learning to classify the brain activities measured by functional magnetic resonance imaging or identify visual stimulus images. Accurate reconstruction of visual stimulus images by using deep learning still remains challenging. This paper proposes an improved deep generative multiview model to further promote the accuracy of reconstructing visual stimulus images. Firstly, an encoder based on residual-in-residual dense blocks is designed to fit the deep and multiview visual features of human natural state, and extract the features of visual stimulus images. Secondly, the structure of original decoder is extended to a deeper network in the deep generative multiview model, which makes the features obtained by each deconvolution layer more distinguishable. Finally, we configure the parameters of the optimizer and compare the performance of various optimizers under different parameter values, and then the one with the best performance is chosen and adopted to the whole model. The performance evaluations conducted on two publicly available datasets demonstrate that the improved model has more accurate reconstruction effectiveness than the original deep generative multiview model.


Assuntos
Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Cabeça
13.
Cogn Neurodyn ; 17(2): 373-384, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37007202

RESUMO

Brain-computer interface (BCI) can obtain text information by decoding language induced electroencephalogram (EEG) signals, so as to restore communication ability for patients with language impairment. At present, the BCI system based on speech imagery of Chinese characters has the problem of low accuracy of features classification. In this paper, the light gradient boosting machine (LightGBM) is adopted to recognize Chinese characters and solve the above problems. Firstly, the Db4 wavelet basis function is selected to decompose the EEG signals in six-layer of full frequency band, and the correlation features of Chinese characters speech imagery with high time resolution and high frequency resolution are extracted. Secondly, the two core algorithms of LightGBM, gradient-based one-side sampling and exclusive feature bundling, are used to classify the extracted features. Finally, we verify that classification performance of LightGBM is more accurate and applicable than the traditional classifiers according to the statistical analysis methods. We evaluate the proposed method through contrast experiment. The experimental results show that the average classification accuracy of the subjects' silent reading of Chinese characters "(left)", "(one)" and simultaneous silent reading is improved by 5.24%, 4.90% and 12.44% respectively.

14.
Artigo em Inglês | MEDLINE | ID: mdl-37874631

RESUMO

Spin-orbit torque (SOT)-induced magnetization switching in ferrimagnetic materials is promising for application in a new generation of information storage devices. Here, we demonstrate SOT-induced field-free magnetization switching of the perpendicularly magnetized CoTb ferrimagnet layer in the IrMn/CoTb bilayer, in which the in-plane magnetic inversion symmetry is broken by a spontaneous in-plane exchange bias (IEB) established by isothermal crystallization of the IrMn layer. We obtain a significant SOT effective field acting on the CoTb layer and a large effective spin Hall angle in this system, derived by the second harmonic voltage measurement method. Moreover, the IrMn/CoTb bilayer demonstrates multistate magnetic switching behavior with different amplitudes of current pulses at zero field, which can mimic the synaptic weight updates in the neuromorphic network. These findings make the IrMn/CoTb bilayer with spontaneous IEB a promising candidate for potential applications in multilevel storage and neuromorphic computing.

15.
BMJ Open ; 12(1): e050280, 2022 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-34983757

RESUMO

OBJECTIVES: To explore the significance of intraoperative common hepatic arterial lymph node dissection in patients with ooesophageal squamous carcinoma (ESCC) without coeliac trunk lymph node metastasis indicated by abdominal enhanced CT. METHODS: Patients aged 18-75 years who underwent oesophagectomy in three medical centres from June 2012 to June 2015, for whom R0 resection was completed and lymph node metastasis in the abdominal trunk was not identified before the operation were retrospectively analysed. The effects of the application value of common hepatic arterial lymph node dissection on survival were evaluated in patients with ESCC without coeliac trunk lymph node metastasis indicated by preoperative CT. According to the eighth version ofAmerican Joint Committee on Cancer (AJCC)/Union for International Cancer Control (UICC) staging, we selected patients with a Pathological Tumor Node Metastasis (pTNM) stage ranging from IA to IVA for analysis. RESULTS: Among the 816 qualified patients, 577 did not have coeliac trunk lymph node metastasis based on preoperative abdominal enhanced CT, and common hepatic arterial lymph node dissection was performed during the operation (observation group). Two hundred and thirty-nine preoperative CT examinations indicated no coeliac trunk lymph node metastasis, and common hepatic arterial lymph node dissection was not performed during the operation (control group). A multifactor Cox proportional hazards model showed no risk factors for overall survival (OS) (adjusted HR (HRadj)=0.91; p=0.404) or disease-free survival (DFS) (HRadj=0.86; p=0.179), regardless of whether common hepatic arterial lymph node dissection was performed. For patients with positive left gastric arterial lymph node metastasis, a multifactor Cox proportional hazards model indicated that common hepatic arterial lymph node dissection was a risk factor for OS (HRadj=0.63; p=0.035) and DFS (HRadj=0.58; p=0.026). CONCLUSIONS: For patients with ESCC without celiac trunk metastasis indicated by abdominal enhanced CT, common hepatic arterial lymph node dissection conferred no survival benefits. However, for patients with left gastric arterial lymph node metastasis, common hepatic arterial lymph node dissection was beneficial.


Assuntos
Carcinoma de Células Escamosas , Excisão de Linfonodo , Adolescente , Adulto , Idoso , Carcinoma de Células Escamosas/cirurgia , Humanos , Linfonodos/diagnóstico por imagem , Linfonodos/patologia , Linfonodos/cirurgia , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Retrospectivos , Adulto Jovem
16.
Nanomaterials (Basel) ; 12(23)2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36500890

RESUMO

Due to its high sensitivity and because it does not rely on the magneto-optical response, terahertz (THz) emission spectroscopy has been used as a powerful time-resolved tool for investigating ultrafast demagnetization and spin current dynamics in nanometer-thick ferromagnetic (FM)/heavy metal (HM) heterostructures. Here, by changing the order of the conductive HM coating on the FM nanometer film, the dominant electric dipole contribution to the laser-induced THz radiation can be unraveled from the ultrafast magnetic dipole. Furthermore, to take charge equilibration into account, we separate the femtosecond laser-induced spin-to-charge converted current and the instantaneous discharging current within the illuminated area. The THz emission spectroscopy gives us direct information into the coupled spin and charge dynamics during the first moments of the light-matter interaction. Our results also open up new perspectives to manipulate and optimize the ultrafast charge current for promising high-performance and broadband THz radiation.

17.
Adv Sci (Weinh) ; 8(7): 2004552, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33854905

RESUMO

Though evaporation-driven electricity generation has emerged as a novel eco-friendly energy and attracted intense interests, it is typically demonstrated in pure water or a very low salt concentration. Integrating evaporation-driven electricity generation and solar steam desalination simultaneously should be more promising. Herein, a polyaniline coated metal-organic frameworks (MOFs) nanorod arrays membrane is synthesized which inherits the merits of both polyaniline and MOFs, demonstrating nice stability, good interfacial solar steam desalination, and evaporation-driven electricity generation. Moreover, an integrated system based on this hybrid membrane achieves good interfacial solar-heating evaporation and prominently enhanced evaporation-driven electricity generation under one sun. Notably, the realization of effective seawater desalination and efficient evaporation-driven electricity generation simultaneously by the non-carbon-based materials is reported for the first time, which provides a new alternative way for cogenerating both freshwater and electricity by harvesting energy from seawater and solar light.

18.
Dalton Trans ; 50(8): 2731-2735, 2021 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-33599638

RESUMO

In this work, a unique photoswitch is reported based on the intrinsic photothermal properties of a HKUST-1 metal-organic framework (MOF) membrane. The HKUST-1 membrane is synthesized through a solid conversion process at room temperature. It exhibits excellent reversible photoswitchable proton conductivity owing to its intrinsic localized photothermal effect with an optimal on/off ratio of 299 at 55 °C under 95% RH. This may have potential application in remote controlled smart devices.

19.
Ann Transl Med ; 9(9): 764, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34268377

RESUMO

BACKGROUND: Andrographolide (Andro), a diterpenoid extracted from Andrographis paniculata, has been shown to attenuate pulmonary fibrosis in rodents; however, the potential mechanisms remain largely unclear. This study investigated whether and how Andro alleviates bleomycin (BLM)-induced NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome activation and epithelial-mesenchymal transition (EMT) in the lung epithelial cells. METHODS: The in vivo effects of Andro were evaluated in a rat model of BLM-induced pulmonary fibrosis. The roles of Andro in BLM-induced NLRP3 inflammasome activation, EMT and AKT/mTOR signaling were investigated using human alveolar epithelial A549 cells. RESULTS: We found that Andro significantly alleviated pulmonary edema and histopathological changes, decreased weight loss, and reduced collagen deposition. Andro downregulated the levels of NLRP3, the adaptor molecule apoptosis-associated speck-like protein containing a CARD (ASC), and Caspase-1 in the lungs of BLM-treated rats, suggesting the inhibitory effect of Andro on NLRP3 inflammasome activation in vivo. Additionally, the symptoms of BLM-mediated EMT phenotype in the lung were also attenuated after Andro administration. In vitro, Andro also markedly inhibited BLM-induced NLRP3 inflammasome activation and EMT in A549 cells. Moreover, Andro inhibited BLM-induced phosphorylation of AKT and mTOR in A549 cells, suggesting that AKT/mTOR inactivation mediates Andro-induced effects on BLM-induced NLRP3 inflammasome activation and EMT. CONCLUSIONS: These data indicate that Andro can reduce BLM-induced pulmonary fibrosis through suppressing NLRP3 inflammasome activation and EMT in lung epithelial cells via AKT/mTOR signaling pathway.

20.
Chem Commun (Camb) ; 56(89): 13840-13843, 2020 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-33084650

RESUMO

Hybrid heterogeneous solid acid catalysts polyoxometalate-decorated metal organic framework (POM@MOFs) thin films were synthesized from POMs and metal hydroxide nanostrands via a self-confinement method at room temperature, which show high hydrolyzing activity (1027.5 µmol g-1 min-1) for ethyl acetate with durable stability and an easy recovery. This provides a general way to easily prepare nano POM@MOF thin film catalysts.

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