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1.
Sensors (Basel) ; 24(3)2024 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-38339723

RESUMO

Accurately extracting pixel-level buildings from high-resolution remote sensing images is significant for various geographical information applications. Influenced by different natural, cultural, and social development levels, buildings may vary in shape and distribution, making it difficult for the network to maintain a stable segmentation effect of buildings in different areas of the image. In addition, the complex spectra of features in remote sensing images can affect the extracted details of multi-scale buildings in different ways. To this end, this study selects parts of Xi'an City, Shaanxi Province, China, as the study area. A parallel encoded building extraction network (MARS-Net) incorporating multiple attention mechanisms is proposed. MARS-Net builds its parallel encoder through DCNN and transformer to take advantage of their extraction of local and global features. According to the different depth positions of the network, coordinate attention (CA) and convolutional block attention module (CBAM) are introduced to bridge the encoder and decoder to retain richer spatial and semantic information during the encoding process, and adding the dense atrous spatial pyramid pooling (DenseASPP) captures multi-scale contextual information during the upsampling of the layers of the decoder. In addition, a spectral information enhancement module (SIEM) is designed in this study. SIEM further enhances building segmentation by blending and enhancing multi-band building information with relationships between bands. The experimental results show that MARS-Net performs better extraction results and obtains more effective enhancement after adding SIEM. The IoU on the self-built Xi'an and WHU building datasets are 87.53% and 89.62%, respectively, while the respective F1 scores are 93.34% and 94.52%.

2.
Small ; 19(9): e2205947, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36541728

RESUMO

The Ti3 C2 Tx film with metallic conductivity and high pseudo-capacitance holds profound promise in flexible high-rate supercapacitors. However, the restacking of Ti3 C2 Tx sheets hinders ion access to thick film electrodes. Herein, a mild yet green route has been developed to partially oxidize Ti3 C2 Tx to TiO2 /Ti3 C2 Tx by introducing O2  molecules during refluxing the Ti3 C2 Tx suspension. The subsequent etching away of these TiO2  nanoparticles by HF leaves behind numerous in-plane nanopores on the Ti3 C2 Tx sheets. Electrochemical impedance spectroscopy shows that longer oxidation time of 40 min yields holey Ti3 C2 Tx (H-Ti3 C2 Tx ) with a much shorter relax time constant of 0.85 s at electrode thickness of 25 µm, which is 89 times smaller than that of the pristineTi3 C2 Tx film (75.58 s). Meanwhile, H-Ti3 C2 Tx film with 25 min oxidation exhibits less-dependent capacitive performance in film thickness range of 10-84 µm (1.63-6.41 mg cm-2 ) and maintains around 60% capacitance as the current density increases from 1 to 50 A g-1 . The findings clearly demonstrate that in-plane nanopores not only provide more electrochemically active sites, but also offer numerous pathways for rapid ion impregnation across the thick Ti3 C2 Tx film. The method reported herein would pave way for fabricating porous MXene materials toward high-rate flexible supercapacitor applications.

3.
Food Chem ; 356: 129643, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-33812190

RESUMO

A rapid screening method of 70 colorants for regulatory control in dyeable foods was established using ultra-high-performance liquid chromatography-hybrid quadrupole-Orbitrap mass spectrometry (UHPLC-Q/Orbitrap MS) with customized accurate-mass database and mass spectral library. A rapid, high-throughput, and simple sample pretreatment condition with low reagent consumption and high recovery was developed on the basis of ultrasound-assisted extraction and dispersion solid-phase extraction. Rapid screening was conducted by comparing the experimentally measured exact mass of the parent and fragment ions, the isotope pattern, and the retention time with the accurate-mass database and by matching the acquired MS/MS spectra against the mass spectral library. The performance of the method was evaluated in terms of linearity, limits of detection, limits of quantitation, recovery, repeatability, reproducibility, and matrix effect. The proposed method was applied for simultaneous analysis of 70 colorants in seven kinds of dyeable foods, and it exhibited great potential for broad, sensitive, and reliable.


Assuntos
Corantes de Alimentos/química , Cromatografia Líquida de Alta Pressão , Bases de Dados Factuais , Alimentos , Limite de Detecção , Reprodutibilidade dos Testes , Extração em Fase Sólida , Espectrometria de Massas em Tandem , Fatores de Tempo
4.
Trials ; 21(1): 77, 2020 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-31937335

RESUMO

BACKGROUND: Acupoint selection is a key factor in the treatment of diseases and has not been well studied. The aim of this trial is to explore the differences in efficacy between compatible acupoints and a single acupoint for patients with functional dyspepsia (FD). METHODS: This randomized controlled trial will be conducted in the First Affiliated Hospital of Changchun University of Chinese Medicine in China. Two hundred and sixteen FD patients will be randomly assigned to the compatible acupoints group, single acupoint group, or sham acupuncture group. This trial will include a 1-week baseline period, a 4-week treatment period, and a 4-week follow-up period. During the 4-week treatment period, patients will receive 20 sessions of acupuncture (weekly cycles of one session per day for 5 consecutive days followed by a 2-day break). The primary outcome will be a change in the Nepean Dyspepsia Life Quality Index from baseline to after the 4-week treatment period. Secondary outcome measures will include the dyspeptic symptom sum score, Overall Treatment Effect questionnaire, and 36-item Short Form survey. Adverse events also will be recorded. Ultraweak photon emission and metabolomics tests will be performed at baseline and at the end of treatment to explore the mechanisms of the differences between compatible acupoints and a single acupoint. DISCUSSION: The results of this trial will allow us to compare the difference in efficacy between compatible acupoints and a single acupoint. The findings from this trial will be published in peer-reviewed journals. TRIAL REGISTRATION: Acupuncture-Moxibustion Clinical Trial Registry, AMCTR-IPC-18000176, registered on 4 March 2019; Chinese Clinical Trial Registry, ChiCTR1900023983, registered on 23 June 2019.


Assuntos
Pontos de Acupuntura/classificação , Terapia por Acupuntura/métodos , Dispepsia/fisiopatologia , Dispepsia/terapia , Terapia por Acupuntura/efeitos adversos , Adolescente , Adulto , Estudos de Casos e Controles , China/epidemiologia , Dispepsia/psicologia , Feminino , Humanos , Masculino , Metabolômica/métodos , Pessoa de Meia-Idade , Fótons , Qualidade de Vida , Projetos de Pesquisa , Inquéritos e Questionários , Resultado do Tratamento , Adulto Jovem
5.
Molecules ; 24(11)2019 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-31163647

RESUMO

Lepidium meyenii is now widely consumed as a functional food and medicinal product, which is known as an enhancer of reproductive health. However, the specific chemical composition and mechanism of action for improving sexual function are unclear. The present study aims at screening and determining the potential compounds, which promote mouse leydig cells (TM3) proliferation. The partial least squares analysis (PLS) was employed to reveal the correlation between common peaks of high performance liquid chromatography (HPLC) fingerprint of L. meyenii and the proliferation activity of TM3. The results suggested that three compounds had good activities on the proliferation of TM3 and promoting testosterone secretion, there were N-benzyl-hexadecanamide, N-benzyl-(9z,12z)-octadecadienamide and N-benzyl-(9z,12z,15z)-octadecatrienamide which might be the potential bioactive markers related to the enhancing sexual ability functions of L. meyenii. The first step in testosterone synthesis is the transport of cholesterol into the mitochondria, and the homeostasis of mitochondrial function is related to cyclophilin D (CypD). In order to expound how bioactive ingredients lead to promoting testosterone secretion, a molecular docking simulation was used for further illustration in the active sites and binding degree of the ligands on CypD. The results indicated there was a positive correlation between the binding energy absolute value and testosterone secretion activity. In addition, in this study it also provided the reference for a simple, quick method to screen the promoting leydig cell proliferation active components in traditional Chinese medicine (TCM).


Assuntos
Lepidium/química , Células Intersticiais do Testículo/citologia , Compostos Fitoquímicos/análise , Compostos Fitoquímicos/farmacologia , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem , Animais , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Análise dos Mínimos Quadrados , Células Intersticiais do Testículo/efeitos dos fármacos , Ligantes , Masculino , Camundongos , Simulação de Acoplamento Molecular , Análise Multivariada , Compostos Fitoquímicos/química , Testosterona/metabolismo
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