CR3 complement receptor: cloning and characterization in rainbow trout.
ABSTRACT The beta 2 integrin CR3 is a leukocyte adhesion heterodimeric glycoprotein which functions both as receptor for iC3b and in several cell-cell and cell-substrate adhesion interactions. In order to elucidate the molecular evolution of the CR3 receptor, here we report the cloning and characterization of its beta2 (CD18) and aM (CD11b) subunits in rainbow trout (Oncorhynchus mykiss). The predicted polypeptide sequences of trout CD18 and CD11b-like exhibit 50, 49, or 61% and 25, 25, or 30% identity with human, mouse, and zebrafish orthologs, respectively. The 'domain' architecture of trout CD18 and CD11b-like subunits retains several characteristics of the mammalian ortholog proteins, such as cysteine-rich regions, N-linked glycosylation sites and several proposed domains and signal sequences (von Willebrand factor type A, Integrin alpha, Integrin B tail, EGF, and Transmembrane domain). The tissue expression profiles of trout CR3 subunits diverge from those of mammalian counterparts, showing the kidney as the main source of the trout CD18 and CD11b-like mRNA transcripts. This is the first report of cloning and characterization of the CR3 receptor in low vertebrates.
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Article: Bit-Flipping BIST[Show abstract] [Hide abstract]
ABSTRACT: A scan-based BIST scheme is presented which guarantees complete fault coverage with very low hardware overhead. A probabilistic analysis shows that the output of an LFSR which feeds a scan path has to be modified only at a few bits in order to transform the random patterns into a complete test set. These modifications may be implemented by a bit-flipping function which has the LFSR-state as an input, and flips the value shifted into the scan path at certain times. A procedure is described for synthesizing the additional bit-flipping circuitry, and the experimental results indicate that this mixed-mode BIST scheme requires less hardware for complete fault coverage than all the other scan-based BIST approaches published so far. Keywords: Mixed-Mode BIST 1. Introduction Built-in self-test (BIST) is one of the most important techniques for testing large and complex systems. The efficiency of a BIST implementation is characterized by the test length and the hardware overhead required to ...06/2000;
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