Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 5 de 5
Filtrar
Más filtros











Base de datos
Intervalo de año de publicación
1.
Materials (Basel) ; 17(14)2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-39063898

RESUMEN

The effects of chromium (Cr) addition ranging 0.1-0.3 wt.% on the microstructure and mechanical properties of Al-7Si-4Cu-0.25Mg (wt.%) alloy have been investigated. The cast Cr-free alloy consisted of α-Al, eutectic Si, Q-Al5Mg8Cu2Si6 and θ-Al2Cu phases. Doping of Cr resulted in the appearance of a polyhedron-shaped α-Al13Cr4Si4 phase with a cubic structure. The Al13Cr4Si4 particles were found to embed with Al2Cu blocks and bring about size reduction for the Al2Cu blocks. The area fraction of Al13Cr4Si4 monotonously increased with Cr content. After T6 treatment, the Al2Cu blocks almost fully dissolved and transformed to θ'-Al2Cu precipitates in the Cr-containing alloys. TEM observation revealed relatively large-sized θ' precipitates attached to Al13Cr4Si4 dispersoids. The Cr-containing alloys showed impressive mechanical properties, with the peak strength up to 452 MPa at room temperature. The ductility exhibited an increasing trend with Cr content, but the strength dropped dramatically when the Cr content reached 0.3 wt.%. It is suggested that the strength contribution from the Al13Cr4Si4 phase is limited, especially at an elevated temperature.

2.
Appl Opt ; 62(35): 9343-9352, 2023 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-38108706

RESUMEN

A terahertz imaging system is considered to be an effective method to study the thermal barrier coating defects in gas turbine engines. However, due to the influence of the system hardware and terahertz wavelength, the imaging system has slow acquisition efficiency, low image resolution, and serious edge blur, which cannot meet the demand for defect detection. To overcome the above defects, a model-driven terahertz image reconstruction method is proposed, which uses simulation data to build datasets, reduces the dependence on experimental data, and has a good reconstruction effect on experimental images. A fusion loss function based on the edge intensity was designed to optimize the edge effect of reconstructed images. Compared with the bicubic, SRCNN, and VDSR methods, the proposed method can achieve better results in terms of visual and evaluation indices for the reduced terahertz images. It is proved that this method can effectively restore the defect contour in the terahertz image, sharpen the edge of the image, and improve the image quality. It has a good application value in the industry.

3.
Medicine (Baltimore) ; 101(4): e28707, 2022 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-35089232

RESUMEN

BACKGROUND: Poststroke depression (PSD) is a syndrome that occurs after stroke. The efficacy of Chinese herbal medicine (CHM) for PSD has also received widespread attention, but there is still a lack of clinical evidence because this overview evaluates the published meta-analyses (MAs)/Systematic reviews (SRs). To provide evidence for the clinical application of CHM in the treatment of PSD. METHODS: Two researchers searched 7 databases for SRs/MAs which are about randomized controlled trials on CHM for PSD. Two investigators use the systematic review assessment tool (AMSTAR-2), the risk of bias in systematic scale, the list of preferred reporting items for systematic reviews and meta-analysis, and the classification of recommended assessments for evaluation, development and evaluation system to assess the included SRs/MAs. RESULTS: Our findings will be published in peer-reviewed journals. CONCLUSION: This study provides evidence-based medical evidence for the impact of CHM on PSD. REGISTRATION NUMBER: INPLASY202210001.


Asunto(s)
Depresión/tratamiento farmacológico , Medicamentos Herbarios Chinos/uso terapéutico , Bases de Datos Factuales , Depresión/etiología , Humanos , Metaanálisis como Asunto , Revisiones Sistemáticas como Asunto
4.
Ann Transl Med ; 9(10): 858, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-34164492

RESUMEN

BACKGROUND: To date, vascular dementia (VaD) lacks effective treatment in clinical practice. There is also growing evidence that VaD may be closely related to the immune response. The development of high-throughput technology, and the recently discovered group of new mediators called competitive endogenous RNAs (ceRNA), provides a unique opportunity to study the immunomodulation of VaD. METHODS: In this study, we used gene expression profiles in the Gene Expression Omnibus (GEO) database to obtain immune-related gene coexpression modules through a weighted gene coexpression network analysis (WGCNA) and gene enrichment analysis. We extracted and merged long non-coding RNA (lncRNA) and microRNA (miRNA) expressions from the GEO database and mapped them with related databases. Subsequently, we used Cytoscape to construct a lncRNA-miRNA-mRNA network, and then we performed an enrichment analysis on the mRNAs in the network to determine their regulatory function. Subsequently, we used an ImmuCellAI immune infiltration analysis and constructed a ceRNA sub-network of related immune cells. Finally, we conducted a gene set enrichment analysis (GSEA) to determine the potential regulatory pathways of the key factors. RESULTS: As a result, we identified the blue module as the key module of immunity and constructed the related CeRNA network. Immune infiltration analysis showed that natural killer T (NKT) cells may be the key immune cells of VaD. Using a Pearson correlation analysis, we identified that B4GALT1, PPP1R3B, MICB, HHAT, DSC2, DNA2, SCARA3, and lncRNA NEAT1 may be the key factors of VaD. Our subsequent GSEA analysis showed that lncRNA NEAT1 may be regulated by NK cells and toll-like receptors. CONCLUSIONS: Our research provides new therapeutic targets for vascular dementia from the immunological perspective for the first time, including B4GALT1, PPP1R3B, MICB, HHAT, DSC2, DNA2, SCARA3, and lncRNA NEAT1, and our research hopes to provide new treatment options for VaD.

5.
Rev Sci Instrum ; 85(11): 113701, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25430114

RESUMEN

To date, rotating mirror (RM) cameras still serve as indispensable imaging equipment for the diagnosis of microsecond transient processes due to their excellent characteristics. This paper, for upgrading the optical information capacity of the cameras, presents the new optical acceleration principle to increase the framing frequency or scanning velocity, the new design theory without principle errors instead of the classical theories with some flaws in principle to have applied to design our simultaneous streak and framing rotating mirror camera with continuous access, and the new rotating mirror with novel structure, made of an aluminum alloy, to have considerably reduced lateral deformation of the RM and improved the performance of the camera.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA