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This study aims to evaluate the impact of image factors on the performance of deep learning models used for ophthalmic ultrasound image diagnosis. A total of 3,373 ophthalmic ultrasound images are used to deeply evaluate the influence of image factors on the performance of deep learning classification models. Inceptionv3, Xception, and the fusion model Inceptionv3-Xception are used to explore how brightness, contrast, gain, noise, size, format, pseudo-color seven image-related factors affect the classification performance of the model. Inceptionv3-Xception has advantages in the recognition accuracy of various image factors. When the image brightness changes, the model's performance shows a downward trend (0.5 vs. 1 vs. 1.8, ACC 95.73 vs. 97.06 vs. 93.54, P < 0.05). When the image contrast changes, the model's performance is comparable (0.5 vs. 1 vs. 1.2, ACC 96.23 vs. 96.95 vs. 97.45, P > 0.05). When the image gain drops to 50 dB, the model's accuracy decreases significantly (50 dB vs. 105 dB, ACC 96.49 vs. 97.57, P < 0.05). When Gaussian noise is added to the image, the model's performance gradually decreases (0.02 vs. 0, ACC 89.48vs97.06, P < 0.05). When the image size drops to 25% of the original image, the model's performance decreases significantly (25% vs. 100%, ACC 93.18 vs. 97.06, P < 0.01). When the image format changes, the model's recognition accuracy is similar (JPG vs. BMP vs. PNG, ACC 96.98 vs. 97.06 vs. 97.06, P > 0.05). The accuracy of the model in recognizing pseudo-color images decreases significantly compared to grayscale images (grayscale vs. pseudo-color, ACC 35.96 vs. 97.06). These results indicate that image quality greatly influences the model training process, and acquiring high-quality images is an important prerequisite for high recognition performance of the model. This study offers valuable insights for the improvement of other robust deep learning models for ophthalmic ultrasound image recognition. • High-quality images are a prerequisite for high model recognition performance. • Reference ranges of parameters in ophthalmic images for intelligent diagnosis. • The robustness of model performance varies among different image factors. • The network structure of the fusion model is more stable than the single model. [ABSTRACT FROM AUTHOR]

Abstract: Several noteworthy Cretaceous tracksites are known in the Huizhou District (Huangshan City) in the Yangtzee valley of southern Anhui Province. These include some that have been known since the late 1970s but have not been studied in detail until now. The footprints described here occur in siliciclastic fluvial deposits in three distinct horizons. The Xiaohutian tracksite in the Upper Cretaceous Xiaoyan Formation is the most interesting, being situated at a historically famous location used as a Taoist and Buddhist shrine. The Xiaohutian tracksite yields an assemblage with three different morphotypes of non-avian theropod tracks including the new ichnotaxon Paracorpulentapus zhangsanfengi that can be attributed to a theropod with relatively short “fleshy” toes showing convergence with the footprints of small ornithopods. A further diagnostic feature is the trackway pattern with relatively short steps. Associated ichnofossils are invertebrate traces that can be assigned to eurybathic forms such as Palaeophycus and ?Planolites or ?Scoyenia. Thus far skeletal remains from the Xiaoyan Formation have proved the pachycephalosaur Wannanosaurus and indeterminate sauropods. The ichnoassemblages enlarge the known dinosaur fauna by small- to medium-sized theropods that are identified here as the trackmakers and that are otherwise rare in Upper Cretaceous deposits of eastern China. The Shangshangen locality is another significant tracksite which has yielded small bird tracks (cf. Koreanaornis) in association with small tracks of non-avian theropods. [Copyright &y& Elsevier]

Abstract: The Wuyishan metallogenic belt, a part of the circum-Pacific tectonomagmatic belt, is considered one of the 19 key metallogenic belts in China because of its abundant mineral resources and vast prospecting potential. Specifically, the North Wuyi area is an important Cu–Pb–Zn polymetal ore-concentrated district in East China. We report new geochronological dates in this area, which suggest that the formation of mineralization-related magmatic rocks have mainly occurred during the Paleozoic and Mesozoic in four stages: the Caledonian (530Ma to 430Ma), Early–Middle Jurassic (183Ma to 160Ma), Early Cretaceous (140Ma to 110Ma), and Late Cretaceous (63Ma to 85Ma). The mineralization events are either coeval or slightly postdate the related magmatic activities. Nappe structures are widespread in the North Wuyi area and play an important role in the formation and preservation of ore deposits, as determined from field observations and structural analyses of mining tunnels. The regional distribution and structural styles of the thrust faults in the North Wuyi area and new 40Ar–39Ar dating results (415Ma to 390Ma) confirm that intensive tectonic activity during the Early Paleozoic, when the South China Block was about to separate from Gondwana, has wiped out evidence of Caledonian mineralization. All nappe structures with regional scales (several thousand meters) were formed during the Early Cretaceous period, with an 40Ar–39Ar age of 120Ma to 129Ma. The thrust direction of the nappe structures is mainly southeast during the Early Cretaceous in the main body and north piedmont of the Wuyi Mountain. These early thrust faults have not only broken or reformed the existing ore deposits, but have also provided hydrothermal ore-forming channels and spaces for metallogenism that are coeval or posterior to the thrust. The subsequent nappe structures thrust mainly from southeast to northwest and overprint the previous southeastward thrust faults. Using 40Ar–39Ar dating of the structural belt, U–Pb SHRIMP zircon dating of the wall rocks, and Re–Os dating of the ore formation, we analyze the genetic connection between the structures and ore bodies in different ore fields. Our results serve as useful information on prospecting for the latent ore body in the North Wuyi area, especially the ore bodies destroyed by faulting activities. [Copyright &y& Elsevier]

Abstract: New geochemical and isotopic data are reported from Cretaceous volcanic rocks of the Ganhang Tectonic Belt, southeast China. Two periods of basaltic eruptions (143±1.1–139±0.7Ma and 105–98Ma), each representing results of previous tectonic events, are recognized in the belt. Rock types associated with the eruptions are significantly different in mineral and chemical composition. For the 143±1.1–139±0.7Ma basalts, 87Sr/86Sr ratio (0.7041–0.7048) and Sm–Nd isotopic compositions (ɛNd =+3.78 to +4.38) suggest that the magma came from the depleted mantle and had not mixed with crustal material. During the second episode of magmatic and tectonic activities (105–98Ma), volcanism was accompanied by intense regional extension and the development of a series of “red basins”. The geochemical characteristics of these basalts exhibit both tholeiite and alkaline olivine-types, indicating inhomogeneous mixing of magma with crustal material. The tholeiites have a medium–high 87Sr/86Sr ratio (0.7054–0.7070) and a low ɛNd value (1.69–0.70), indicating that the magma of these basalts came from an unchanged mantle. The alkaline olivine basalts, on the other hand, have a relatively higher 87Sr/86Sr ratio (0.7076–0.7080) and a relatively lower value of ɛNd (−6.43 to −5.18), suggesting that these magmas came from mantle enriched by mixing with subducted crustal material. Based on comprehensive geological analyses, it is concluded that an extensional environment existed in the region from early in the Early Cretaceous, and the Ganhang Belt represents the main rift zone in southeast China during much of the Early Cretaceous. [Copyright &y& Elsevier]