85 research outputs found
A new broad spectrum disinfectant suitable for the food industry
A unique biocide composition (patent pending) that is formed from a hydrogen peroxide and sodium hypochlorite mixture was investigated. A biocidal complex is formed by adding the peroxide to the hypochlorite in an amount so that the weight ratio of the peroxide to the hypochlorite is no less than 1:10. The chemical structure of this biocidal complex is uncertain but we postulate that it is a semi-stable complex, whose stability is disrupted by heat, acid, U/V exposure and the presence of organic matter (i.e., microbes) The antimicrobial activity of the biocidal complex is most likely a combination effect between oxidation and reductive mechanisms The biocidal complex needed from one sixth to one half the concentration of hydrogen peroxide and from one twentieth to one half that of sodium hypochlorite to kill a range of Gram-positive and Gram-negative cells. In the case of bacterial spores (Bacillus sp.), MICs of the biocidal complex ranged from one twentieth to one half and from one fourth to one half for hydrogen peroxide and sodium hypochlorite, respectively. FIC values for both bacterial cells and spores were less than one. FIC values of less than one indicate that a synergistic effect exists between biocide components. The activity of the biocide is stable at alkaline pH, with a half-life of at least 42 days. It is non-corrosive and can be effective in both a dip and spray mode against bacterial cells in their planktonic or sessile state. Our studies indicate that sodium hypochlorite is not only synergistic with hydrogen peroxide but with sodium peroxide as well The use of this biocidal complex may provide a safe, effective and easy method for killing potential pathogens as well as for disinfecting and removing biofilms, as they pose a threat to human safety, particularly in the Food Industry
Evolution of the sand lizards (Lacertilia: Iguanidae): phylogeny, convergence, evolutionary rates, and heterochrony
A Color Transformation For The Compression Of CMYK Images
A CMYK image is often viewed as a large amount of device-dependent data ready to be printed. In several circunstances, CMYK data needs to be compressed, but the conversion to and from device-independent spaces is imprecise at best. In this paper, with the goal of compressing CMYK images, color space transformations were studied. In order to have a practical importance we developed a a new transformation to a YYCC color space, which is deviceindependent and image-independent, i.e. a simple linear transformation between device-dependent color spaces. The transformation from CMYK to YYCC was studied extensively in image compression. For that a distortion measure that would account for both device-dependence and spatial visual sensitivity has been developed. It is shown that transformation to YYCC consistently outperforms the transformation to other device-dependent 4D color spaces such as YCbCrK, while being competitive with the image-dependent KLT-based approach. Other interesting conclusions were also drawn from the experiments, among them the fact that color transformations are not always advantageous over independent compression of CMYK color planes and the fact that chrominance subsampling is rarely advantageous. 1
UNIVERSALITY OF SURFACE EXPONENTS OF SELF-AVOIDING WALKS ON A MANHATTAN LATTICE
The authors use phenomenological renormalization group techniques to study the bulk and surface properties of self-avoiding walks on a Manhattan lattice. They find that, as is the case for the bulk exponents, the underlying bond directionality does not change the universality class of the surface exponents relative to undirected lattices. They also obtain an estimate for the position of the binding transition
Fast JPEG Encoding for Color Fax Using HVQ
We derive a JPEG compliant image compressor which is based on hierarchical vector quantization (HVQ). The goal is to reduce complexity while increasing compression speed. For each block, the DCT DC coefficient is encoded in the regular way while the residual is mapped through HVQ to a pre-computed bit-stream corresponding to the compressed DCT AC coefficients. Approximation quality is generally good for high compression ratios. Color Fax is the primary application target for the proposed system. 1. INTRODUCTION TO COLO
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