A study was conducted to determine if the fermentation conditions of Nham (Thai fermented sausage) were effective against Escherichia coli O157:H7 and three non-O157:H7 Shiga toxin-producing E. coli, O8 (stx2+, eaeA-), O111 (stx1+, eaeA+) and untypable O serogroup (stx1+, eaeA-) strain, compared with non pathogenic E. coli, E780 as a negative control. Nham was produced using starter cultures of...

We use the cosmic microwave background angular power spectra to place upper limits on the degree to which global defects may have aided cosmic structure formation. We explore this under the inflationary paradigm, but with the addition of textures resulting from the breaking of a global O(4) symmetry during the early stages of the Universe. As a measure of their contribution, we use the fraction...

In this paper we consider the design of a four-cavity microwave circuit for a high-gain K-band gyroklystron. The goal is to use this device to test a high gradient linear accelerator structure. The frequency doubling circular gyroklystron uses a beam voltage of 500 kV, beam current of 200 A in the circular TE011 mode and provides an output in the TE021 mode. We study the behavior of the four-ca...

We review recent progress in the physics and technology of cold cathode electron emitters. The characteristics of emission from field emitter arrays, photocathodes, and ferroelectrics are presented, together with a summary of the understanding of the physics involved. The paper concludes with a description of L-band micropulse gun, based on secondary emission in an RF cavity. Emphasis is placed...

The microwave band fixed wireless access (FWA) systems are expected to operate in non-line-of-sight (NLOS) environments in order to loosen the restrictions on antenna installation at a subscriber station (SS). In addition, it is planning to adopt array antenna at a SS in the next generation FWA. In this case, Direction of arrival (DOA) is a one of the important propagation parameters. We carrie...

The detection and disposal of anti-personnel landmines is one of the most diicult and intractable problems faced in ground connict. This paper rst presents current detection methods which use a separated aperture microwave sensor and an artiicial neural-network pattern classiier. Several data-speciic pre-processing methods are developed to enhance neural-network learning. In addition, a general...

We investigate cosmological structure formation seeded by topological defects which may form during a phase transition in the early universe. First we derive a partially new, local and gauge invariant system of perturbation equations to treat microwave background and dark matter fluctuations induced by topological defects or any other type of seeds. We then show that this system is well suited ...

We discuss the possibility to constrain the relation between redshift and temperature of the cosmic microwave background (CMB) using multifrequency Sunyaev-Zeldovich (SZ) observations. We have simulated a catalog of clusters of galaxies detected through their SZ signature assuming the sensitivities that will be achieved by the Planck satellite at 100, 143 and 353 GHz, taking into account the in...

In this paper a novel bio-inspired neural network (BINN) has been created for microwave diversity imaging compression. This work focuses on, firstly incorporating BINN and back propagation learning into a multiresolution, and secondly, training the highpass channel for perfect reconstruction so that the BINN filterbank within realistic coding conditions. Experiments have shown the robustness an...

The paper reviews the properties of periodic and guiding structures which now play an important part in the operation of components, antennas, electron tubes and low-noise amplifiers. An account is first given of dispersive propagation in periodic-loaded lines, showing how the frequency characteristic breaks into pass and stop bands. The formation of forwardand backward-space harmonics and the ...