Reshock behavior of silicon carbide

The shear strength of a ceramic is an important material property which is indicative of its behaviour under impact loading condition. The brittle nature of ceramics suggest that impact loading of a ceramic attained due to subsonic impact could change the initial shear strength of the ceramic. If so, the subsequent behaviour of the ceramic may not be dependent on the the initial strength. Thus, it is necessary to determine the shear strength of a cermaic under single and multiple impacts. The present work determines the change in the shear strength of silicon carbide under a single shock, shock-reshock, and shock-release wave propagation, respectively. The material used in this work is marketed by CERCOM Inc. as SiC-B. The results of this work indicate that shear strength of SiC-B increases under shock-reshock

Computational prediction of microRNA genes in silkworm genome

MicroRNAs (miRNAs) constitute a novel, extensive class of small RNAs (~21 nucleotides), and play important gene-regulation roles during growth and development in various organisms. Here we conducted a homology search to identify homologs of previously validated miRNAs from silkworm genome. We identified 24 potential miRNA genes, and gave each of them a name according to the common criteria. Interestingly, we found that a great number of newly identified miRNAs were conserved in silkworm and Drosophila, and family alignment revealed that miRNA families might possess single nucleotide polymorphisms. miRNA gene clusters and possible functions of complement miRNA pairs are discussed