In this paper, the most appropriate buffer structure, page replacement policy and buffering scheme for closest pairs queries, where both spatial datasets are stored in R-trees, are investigated. Three buffer structures (i.e. single, hybrid and by levels) over two buffering schemes (i.e. local to each R-tree, and global to the query) using several page replacement algorithms (e.g. FIFO, LRU, 2Q,...

the stripe (yellow) rust in wheat is one of the most important plant diseases in iran. since 1993 several epidemics have occurred in iran causing the breakdown of widely util-ized sources of resistance in wheat cultivars. twenty-seven pathotypes were identified during 2003 and 2004 in greenhouse tests. pathotypes 6e6a+, 6e22a+, 6e130a+, 6e134a+, 6e142a+, 6e158a+, 134e130a+ and 134e142a+ were mo...

objective(s):ischemia is described as organs and tissues are destitute of oxygen due to decreased arterial or venous blood flow. many mechanisms play role in cell death happened as a consequence of a new blood flow is needed for both cell regeneration and to clean toxic metabolites during ischemia and later. lung damage induced by ischemia/reperfusion (i/r) is a frequent problem in lung transpl...

Staphylococcus aureus possesses three MsrA enzymes (MsrA1, MsrA2, MsrA3) that reduce the S-epimer of methionine sulfoxide (MetO) and an MsrB enzyme that reduces R-MetO. The four msr genes are expressed from three different promoters. The msrA1/msrB genes are coexpressed. To determine the expression pattern of msr genes, three independent reporter strains were constructed where msr promoter was ...

A novel removing polymerase chain reaction (R-PCR) technique was developed, which can eliminate undesired genes, cycle by cycle, with efficiencies of 60.9% (cDNAs), 73.6% (genomic DNAs), and ~ 100% (four DNA fragments were tested). Major components of the R-PCR include drivers, a thermostable restriction enzyme - ApeKI, and a poly(dA) adapter with mismatched restriction enzyme recognition sites...