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The lower Cambrian trilobite Eodontopleura Chien and Lin in Yin and Lee 1978 from South China was once thought to be an ancestor of the post-Cambrian trilobite Odontopleurida due to its unique odontopleurid-like glabella. Here, we revise this genus as an oryctocephalid based on the articulated exoskeletons found recently in the Balang Formation (Cambrian Series 2, Stage 4) of South China. Phylogenetic analysis supports that Eodontopleura represents a typical example of trilobite convergent evolution, suggesting that even the most exclusive features may have been repeated in the evolutionary history of trilobites, which additionally reminds us of the universality of convergence and its possible misleading effect on trilobite taxonomic studies. Moreover, our discovery indicates the remarkable specialisation potential of oryctocephalids, which highlights the evolution of early deep-water trilobites. [ABSTRACT FROM AUTHOR]

Pressure induced cavitation is a promising heat dissipation technology since it enables phase-change heat transfer at relatively low temperature. In this study, the sustainability properties of induced cavitation in protruding structure are studied by the Lattice Boltzmann Method. The simulation results suggest that a typical cavitation process is composed of four stages: 1st: cavitation appears in front of inflow liquid, 2nd: bubble shedding, 3rd: cavitation area gradually stretches towards downstream, 4th: cavitation area reaches equilibrium steady state. The flow pattern varies as the increase of inlet velocity. Only inlet velocity greater than "critical inlet velocity" can cavitation bubbles exist perpetually in protruding structure. The value of the critical inlet velocity decreases as the increase of width ratio and the resulting cavitation number falls to 1.8–2.1. The main mechanism for cavitation in protruding structure is pressure drop, rather than shear force. [ABSTRACT FROM AUTHOR]