Genetics

Scientists identify a key driver of myelin repair

New research from scientists at the Wu Tsai Neurosciences Institute at Stanford University has identified a key driver of myelination, the formation of protective fatty sheaths around nerve fibers.

Oncology & Cancer

New insights into the roles of cell mechanics in tumor malignancy

Cancer, as a life-threatening disease, has been a major research focus. Understanding the mechanisms of tumor progression has been a significant challenge. In recent years, increasing evidence has indicated a correlation ...

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Actinopterygii

The Actinopterygii /ˌæktɨnɒptəˈrɪdʒi.aɪ/ or ray-finned fishes constitute a class or sub-class of the bony fishes.

The ray-finned fishes are so called because they possess lepidotrichia or "fin rays", their fins being webs of skin supported by bony or horny spines ("rays"), as opposed to the fleshy, lobed fins that characterize the class Sarcopterygii which also, however, possess lepidotrichia. These actinopterygian fin rays attach directly to the proximal or basal skeletal elements, the radials, which represent the link or connection between these fins and the internal skeleton (e.g., pelvic and pectoral girdles).

In terms of numbers, actinopterygians are the dominant class of vertebrates, comprising nearly 96% of the 25,000 species of fish. They are ubiquitous throughout fresh water and marine environments from the deep sea to the highest mountain streams. Extant species can range in size from Paedocypris, at 8 millimetres (0.31 in), to the massive Ocean Sunfish, at 2,300 kilograms (5,100 lb), and the long-bodied Oarfish, to at least 11 metres (36 ft).

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