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1.
Molecules ; 28(15)2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37570767

RESUMEN

High-performance non-enzymatic glucose sensor composite electrodes were prepared by loading Ni onto a boron-doped diamond (BDD) film surface through a thermal catalytic etching method. A carbon precipitate with a desired thickness could be formed on the Ni/BDD composite electrode surface by tuning the processing conditions. A systematic study regarding the influence of the precipitated carbon layer thickness on the electrocatalytic oxidation of glucose was conducted. While an oxygen plasma was used to etch the precipitated carbon, Ni/BDD-based composite electrodes with the precipitated carbon layers of different thicknesses could be obtained by controlling the oxygen plasma power. These Ni/BDD electrodes were characterized by SEM microscopies, Raman and XPS spectroscopies, and electrochemical tests. The results showed that the carbon layer thickness exerted a significant impact on the resulting electrocatalytic performance. The electrode etched under 200 W power exhibited the best performance, followed by the untreated electrode and the electrode etched under 400 W power with the worst performance. Specifically, the electrode etched under 200 W was demonstrated to possess the highest sensitivity of 1443.75 µA cm-2 mM-1 and the lowest detection limit of 0.5 µM.

2.
Molecules ; 28(11)2023 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-37298787

RESUMEN

The transformations of physicochemical properties on manganese oxides during peroxymonosulfate (PMS) activation are vital factors to be concerned. In this work, Mn3O4 nanospheres homogeneously loaded on nickel foam are prepared, and the catalytic performance for PMS activation is evaluated by degrading a target pollutant, Acid Orange 7, in aqueous solution. The factors including catalyst loading, nickel foam substrate, and degradation conditions have been investigated. Additionally, the transformations of crystal structure, surface chemistry, and morphology on the catalyst have been explored. The results show that sufficient catalyst loading and the support of nickel foam play significant roles in the catalytic reactivity. A phase transition from spinel Mn3O4 to layered birnessite, accompanied by a morphological change from nanospheres to laminae, is clarified during the PMS activation. The electrochemical analysis reveals that more favorable electronic transfer and ionic diffusion occur after the phase transition so as to enhance catalytic performance. The generated SO4•- and •OH radicals through redox reactions of Mn are demonstrated to account for the pollutant degradation. This work will provide new understandings of PMS activation by manganese oxides with high catalytic activity and reusability.


Asunto(s)
Nanosferas , Níquel , Manganeso , Óxidos/química , Peróxidos/química
3.
Med Eng Phys ; 125: 104118, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38508807

RESUMEN

In terms of speed and accuracy, the deep learning-based polyp segmentation method is superior. It is essential for the early detection and treatment of colorectal cancer and has the potential to greatly reduce the disease's overall prevalence. Due to the various forms and sizes of polyps, as well as the blurring of the boundaries between the polyp region and the surrounding mucus, most existing algorithms are unable to provide highly accurate colorectal polyp segmentation. Therefore, to overcome these obstacles, we propose an adaptive feature aggregation network (AFANet). It contains two main modules: the Multi-modal Balancing Attention Module (MMBA) and the Global Context Module (GCM). The MMBA extracts improved local characteristics for inference by integrating local contextual information while paying attention to them in three regions: foreground, background, and border. The GCM takes global information from the top of the encoder and sends it to the decoder layer in order to further investigate global contextual feature information in the pathologic picture. Dice of 92.11 % and 94.76 % and MIoU of 91.07 % and 94.54 %, respectively, are achieved by comprehensive experimental validation of our proposed technique on two benchmark datasets, Kvasir-SEG and CVCClinicDB. The experimental results demonstrate that the strategy outperforms other cutting-edge approaches.


Asunto(s)
Algoritmos , Moco , Procesamiento de Imagen Asistido por Computador
4.
Polymers (Basel) ; 14(11)2022 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-35683956

RESUMEN

High thermal conductivity and good mechanical properties are significant for photo-thermal conversion in solar energy utilization. In this work, we constructed a three-dimensional network structure in polyethylene (PE) and ethylene-propylene-diene monomer (EPDM)-based phase change composites by mixing with a carbon nanotube (CNT). Two-dimensional flake expanded graphite in PE-EPDM-based phase change materials and one-dimensional CNT were well mixed to build dense three-dimensional thermal pathways. We show that CNT (5.40%wt)-PE-EPDM phase change composites deliver excellent thermal conductivity (3.11 W m-1 K-1) and mechanical properties, with tensile and bending strength of 10.19 and 21.48 MPa. The melting and freezing temperature of the optimized phase change composites are measured to be 64.5 and 64.2 °C and the melting and freezing latent enthalpy are measured to be 130.3 and 130.5 J g-1. It is found that the composite phase change material with high thermal conductivity is conducive to the rapid storage of solar energy, so as to improve the efficiency of heat collection.

5.
Nanomaterials (Basel) ; 9(3)2019 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-30841489

RESUMEN

In this work, the CMK-3 is successfully prepared with SBA-15 as the template and first annealed to 2000 °C to improve thermal conductivity. The annealed CMK-3 has a thermal conductivity of 6.981 W m-1 K-1 higher than un-annealed CMK-3. The annealed CMK-3 is used to encapsulate the RT44HC, and RT44HC/annealed CMK-3 has 10-fold of thermal conductivity and enhanced thermal stability than RT44HC. The RT44HC/annealed CMK-3 has a large melting enthalpy of 177.8 J g-1 and good thermal stability. The RT44HC/annealed CMK-3 has optical absorptive coefficient of visible range of solar spectrum, which identify seven-fold higher than RT44HC. The RT44HC/annealed CMK-3 has great photo-thermal performance, and the photo-driven energy charging and discharging rate of RT44HC/annealed CMK-3 is almost 30-fold larger than the RT44HC. The results show that the annealed CMK-3 is a great mesoporous carbon nanomaterial for phase change materials and the annealed CMK-3 based phase change material has great potential in solar thermal utilizations such as solar water heating system and solar heating building systems.

6.
Mol Med Rep ; 16(4): 4113-4118, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28765958

RESUMEN

Interleukin-12 (IL-12) serves an important role in immune responses and antitumor activity. The study of the association between autophagy and cancer cells remains controversial. The present study aimed to investigate the effect of IL­12 on autophagy in the human breast cancer cell lines MDA­MB­231 and MCF­7, and the possible molecular mechanism. Breast cancer cells were treated with different concentrations of recombinant IL­12. The expression of the autophagy-associated protein microtubule­associated protein light chain 3 (LC3) was determined using western blot analysis, fluorescein isothiocyanate­labeled LC3 was detected using fluorescence microscopy and autophagosomes were examined using transmission electron microscopy. Alterations in the phosphatidylinositol 3­kinase/Rac­α serine/threonine protein kinase (PI3K/Akt) and 5'­AMP­activated protein kinase subunit ß­1 (AMPK) pathways, in addition to pathway­associated proteins, were detected using western blotting, following treatment with IL­12 and pretreatment with the PI3K/Akt activator insulin­like growth factor or the AMPK inhibitor compound C. It was observed that IL­12 was able to upregulate the expression of the autophagy­associated protein LC3 in a concentration­ and time­dependent manner, and induce the formation of autophagosomes in the two cell lines, and that the above effects involved the inhibition of the PI3K/Akt signaling pathway and the activation of the AMPK signaling pathway.


Asunto(s)
Proteínas Quinasas Activadas por AMP/metabolismo , Autofagia/efectos de los fármacos , Neoplasias de la Mama/enzimología , Neoplasias de la Mama/patología , Interleucina-12/farmacología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal/efectos de los fármacos , Autofagosomas/efectos de los fármacos , Autofagosomas/metabolismo , Autofagosomas/ultraestructura , Neoplasias de la Mama/ultraestructura , Línea Celular Tumoral , Técnica del Anticuerpo Fluorescente , Humanos , Proteínas Asociadas a Microtúbulos/metabolismo
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