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1.
IEEE Trans Med Imaging ; 43(1): 542-557, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37713220

RESUMEN

The early detection of glaucoma is essential in preventing visual impairment. Artificial intelligence (AI) can be used to analyze color fundus photographs (CFPs) in a cost-effective manner, making glaucoma screening more accessible. While AI models for glaucoma screening from CFPs have shown promising results in laboratory settings, their performance decreases significantly in real-world scenarios due to the presence of out-of-distribution and low-quality images. To address this issue, we propose the Artificial Intelligence for Robust Glaucoma Screening (AIROGS) challenge. This challenge includes a large dataset of around 113,000 images from about 60,000 patients and 500 different screening centers, and encourages the development of algorithms that are robust to ungradable and unexpected input data. We evaluated solutions from 14 teams in this paper and found that the best teams performed similarly to a set of 20 expert ophthalmologists and optometrists. The highest-scoring team achieved an area under the receiver operating characteristic curve of 0.99 (95% CI: 0.98-0.99) for detecting ungradable images on-the-fly. Additionally, many of the algorithms showed robust performance when tested on three other publicly available datasets. These results demonstrate the feasibility of robust AI-enabled glaucoma screening.


Asunto(s)
Inteligencia Artificial , Glaucoma , Humanos , Glaucoma/diagnóstico por imagen , Fondo de Ojo , Técnicas de Diagnóstico Oftalmológico , Algoritmos
2.
J Hazard Mater ; 414: 125487, 2021 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-33676255

RESUMEN

Plasma Cu-decorated TiO2-x/CoP particle-level hierarchical heterojunction photocatalysts with surface engineering were fabricated through solvothermal and solid phase reduction strategies. The CoP nanoparticles not only serve as a cost-effective cocatalyst but also provide abundant surface active sites, which facilitate rapid transfer of photogenerated carriers. The Ti3+ and oxygen vacancy defects extend photoresponse from UV to visible light region, and enhance the separation efficiency of photogenerated carriers efficiently. Because of surface plasma resonance (SPR) of Cu, Cu/TiO2-x/CoP with average particle size of 100-200 nm has significant photothermal effect, in which the temperature of Cu/TiO2-x/CoP is increased by 76 °C with irradiation for 30 s, ~ 8 times higher than that of the original TiO2. Cu/TiO2-x/CoP exhibits a high photocatalytic degradation rates for highly toxic 2,4-dichlorophenol (99.2%) and 2,4,6-trichlorophenol (98.5%), which higher 7.6 and 8.9 times than the initial TiO2, respectively. Thanks to the particle-level hierarchical heterojunction, the efficient surface engineering and SPR effect favoring the spatial charge separation, Cu/TiO2-x/CoP shows excellent photocatalytic-photothermal Performance. This particle-level hierarchical heterojunction architectural design provides a new insight for synthesizing particulate photocatalysts with high-efficiency.

3.
J Colloid Interface Sci ; 568: 255-263, 2020 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-32092554

RESUMEN

Three-dimensional mesoporous graphite-like carbon nitride (Meso-g-C3N4/WP/Meso-g-C3N4) laminated heterojunction nanosheets are successfully synthesized by solid-phase in situ reduction combined with high temperature calcination. Meso-g-C3N4/WP/Meso-g-C3N4 has a relatively high specific surface area of 82 m2 g-1, a large pore size of 8-15 nm, and a narrow band gap of ~2.7 eV. The solar-driven photocatalytic reaction hydrogen production rate (~198.1 µmol h-1g-1) for Meso-g-C3N4/WP/Meso-g-C3N4 3D laminated heterojunctions is approximately 10 times higher than that of pristine g-C3N4. This discrepancy can be attributed to the synergistic effect of the 3D interbed heterojunction structure, which favors the spatial separation of photogenerated charge carriers due to its suitable band positions; its nanosheet structure, favoring the charge transfer to surface; and its mesoporous structures, offering more surface active sites and facilitating mass transfer. This novel sandwich-like laminated heterojunction structure offers new insights for the fabrication of other high-performance photocatalysts.

4.
Nanotechnology ; 30(48): 485401, 2019 11 29.
Artículo en Inglés | MEDLINE | ID: mdl-31532759

RESUMEN

Plasmon Ag and co-catalyst Co x P decorated mesoporous graphite carbon nitride nanosheet assemblies have been synthesized via a template-calcination and ball milling strategy combined with photoreduction. The obtained composites are characterized by x-ray diffraction, Fourier transmission infrared spectroscopy, x-ray photoelectron spectroscopy, transmission electron microscopy, and UV-vis diffuse reflectance spectroscopy. The results show that the sample assembly with mesoporous structure has specific surface area of 50.4 m2 g-1, pore size of 11.3 nm and pore volume of 0.21 cm3 g-1. The Ag and Co x P nanoparticles are decorated on the surface of graphite carbon nitride uniformly. Under solar light irradiation, the photocatalytic degradation rate of ceftazidime for the prepared sample assembly is up to ∼92%, and the photocatalytic reaction rate constant is about 10 times higher than that of bare graphite carbon nitride. Moreover, the sample assembly also exhibits a solar-driven photocatalytic hydrogen production rate of 96.66 µmol g-1 h-1. It can attributed to the surface plasmon resonance effect of Ag nanoparticles and Co x P co-catalyst promoting the spatial charge separation and the mesoporous structure providing more surface active sites and favoring mass transfer. This special structure offers new insights for fabricating other high-performance photocatalysts with high spatial charge separation.

5.
J Hazard Mater ; 377: 330-340, 2019 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-31173983

RESUMEN

Novel nano-zero-valent iron (Fe0)/MnOx/BiVO4 ternary magnetic assemblies are fabricated through hydrothermal and photo-deposition strategy. The assemblies are characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, photoluminescence, X-ray photoelectron spectroscopy, and UV-vis diffuse reflectance spectroscopy. Fe0 as a reduction cocatalyst are deposited on surface of monoclinic BiVO4 decahedron supersturcture. Meanwhile, MnOx as an oxidation cocatalyst is selectively anchored on oxidative {110} facet of BiVO4 by photodeposition. The photogenerated electrons and holes can be transmitted to Fe0 and MnOx, respectively, which favors the spatial charge separation. The adjunction of Fe0 significantly enhances light absorption, and forms a photocatalysis-Fenton coupling system simultaneously. The assemblies with narrow band gap of 2.10 eV display an exceptional photocatalytic activity, and the visible-light-driven photocatalytic degradation ratio of 2,4-dichlorophenol and Bisphenol A are up to 95.4 and 91.4%, respectively, which are several times higher than that of pristine BiVO4. This is ascribed to the selective decoration of Fe0 and MnOx favoring the spatial charge separation, and the photocatalysis-Fenton coupling system enhancing degradation. Moreover, the superior magnetic property due to Fe0 decoration realizes magnetic separation of catalysts, which is favorable in practical applications.

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