background escherichia coli o157:h7 is an enteric pathogen which can be frequently found asymptomatically in ruminant mammals, but can cause diseases from mild diarrhea to hemolytic uremic syndrome in humans. methods we developed fluorescent amplification-based specific hybridization (flash–pcr) assay to detect the stx-encoding gene stx-1 of e. coli o157:h7. result pcr product of 336 bp was suc...

background & objectives: although isoniazid is the most efficient in killing the tuberculosis bacilli, resistance to this drug also develops most readily. mutations in katg, inha and ahpc are responsible for isoniazid resistance in a large proportion of tuberculosis cases. the frequency of these mutations varies with population samples, however. this study provided the first molecular character...

Using a six-orientifold on top of a NS-fivebrane we construct a chiral N = 1 supersymmetric gauge theory in four dimensions with gauge group SU(Nc) and matter in the symmetric, antisymmetric and (anti)fundamental representations. Anomaly cancellation is fulfilled by the requirement of a smooth RR 7-form charge distribution and leads us to the introduction of 8 half D-sixbranes ending on the NS-...

We discuss nonplanar anomalies in noncommutative gauge theories. In particular we show that a nonplanar anomaly exists when the external noncommutative momentum is zero and that it leads to a non-conservation of the associated axial charge. In the case of nonplanar local anomalies, a cancellation of the anomaly can be achieved by a Green-Schwarz mechanism. In an example of D3 branes placed on a...

We derive the general form of the anomaly for chiral spinors and self-dual antisymmetric tensors living on D-brane and O-plane intersections, using both path-integral and index theorem methods. We then show that the anomalous couplings to RR forms of D-branes and O-planes in a general background are precisely those required to cancel these anomalies through the inflow mechanism. This allows, fo...

Intersecting Dp-branes often give rise to chiral fermions living on their intersections. We study the construction of four-dimensional chiral gauge theories by considering configurations of type II D(3 + n)-branes wrapped on non-trivial n-cycles on T × (R/ZN), for n = 1, 2, 3. The gauge theories on the four non-compact dimensions of the brane world-volume are generically chiral and non-supersym...

abrin known as ribosome inactivating protein’s (rip) it is a high cytotoxic plant protein. high lethality and low cost and easy access to plant and seeds lead to this toxin used in crimes and terrorist acts. because obtaining purified toxins requires advanced laboratory equipment and complex procedures, so, it appears that the perpetrators of such crimes use crude extracts. as a result, remaini...

avian influenza virus (aiv) infection is a major cause of bird or human mortality and morbidity, therefore the rapid identification of the virus is of important clinical and epidemiological implication. methods: a multiplex reverse transcriptase pcr (rt-pcr) was optimized for the detection of influenza a virus and the h5 and h9 subtypes. the influenza type a specific primers were directed to th...

We use the BRST formalism to classify the gauge orbits of type II string theory’s Ramond-Ramond (RR) field strengths under large RR gauge transformations of the RR gauge potentials. We find that this construction is identical to the AtiyahHirzebruch spectral sequence construction of twisted K-theory, where the AtiyahHirzebruch differentials are the BRST operators. The actions of the large gauge...