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Chao-Chin Chang

Publications and source records attributed to Chao-Chin Chang.

2 recordsLinked to original sources

The Sedimentary Geochemistry and Paleoenvironments Project Phase 2 data release: An open data resource for the study of Earth's environmental history

Geochemical data from sedimentary rocks are the primary source of information regarding Earth's surface evolution through time, including its air and water envelopes and interactions with life and deep Earth processes. The Sedimentary Geochemistry and Paleoenvironments Project (SGP) is a scientific consortium centered around open data and community-driven development of cyberinfrastructure tools and resources for sedimentary geochemistry and Earth history. Here we describe the SGP Phase 2 data release, which focused on incorporating Paleoproterozoic and Mesoproterozoic (2500–1000 million years ago) data and better accommodating carbonate data. This data release was built through the involvement of >200 researchers worldwide in academia, government, and industry, and provides the largest available public data resource for our user community in the academic fields of geochemistry, sedimentology, tectonics, paleontology, Earth history, and paleoclimate, as well as the petroleum and minerals industries. The dataset now encompasses 126,006 samples and 4,132,371 geochemical analyses. In addition to direct entry by SGP Team Members, we have ingested and incorporated datasets from the Geoscience Australia OZCHEM database, the Alberta Geological Survey, and the Deep-Time Marine Sedimentary Element Database (DM-SED) compilation. This paper details sampling in the Phase 2 dataset with respect to age, geography, lithology, and other geological characteristics, documents access via our search website and API, discusses possible issues and/or biases in the dataset that could impact analyses, describes plans for governance and stewardship of data from Indigenous lands, and serves as the citable reference paper for the data release.

Chemical Geology↗

Identification of Chelonid herpesvirus 5 (ChHV5) in endangered green turtles (Chelonia mydas) with fibropapillomatosis in Asia

Fibropapillomatosis (FP), a debilitating tumor disease of sea turtles, was first identified in green turtles [ Chelonia mydas (Linnaeus, 1758)] in Florida in 1938. In recent decades, FP has been observed globally and is an emerging panzootic disease in sea turtles. However, few reports of FP in Asia exist. Here, we provide the first evidence of Chelonid herpesvirus 5 (ChHV5) DNA associated with FP in endangered green turtles from Taiwan, through molecular characterization, phylogenetic analysis, and histopathological examination. In our study, ChHV5 was successfully detected by PCR in the FP tumor lesions of green turtles. The sequences were found to be consistent with those of tumor-inducing viruses shown to affect sea turtles in the other parts of the world. ChHV5 RNA from the FP tissues was further detected by RT-PCR, indicating active replication of the viruses inside FP tumors. In addition to the molecular evidence of ChHV5 in FP, epidermal intranuclear inclusions were identified in tumor lesions upon histopathological examination. This further suggests that ChHV5 should be in a transcriptionally active (i.e., non-latent) state in FP tumors of affected green turtles. The phylogenetic tree revealed that ChHV5 from the green turtles in Taiwan were closest to the ChHV5 from Hawaii, Puerto Rico, and Sao Tome. For conservation of endangered sea turtles, ChHV5 should be considered an emerging virus, which threatens sea turtles in marine waters in Asia.

Bulletin of Marine Science↗