Chiral color symmetry and possible G′G'-boson effects at the Tevatron and LHC

A gauge model with chiral color symmetry is considered and possible effects of the color $G'$-boson octet predicted by this symmetry are investigated in dependence on two free parameters, the mixing angle $\theta_G$ and $G'$ mass $m_{G'}$. The allowed region in the $m_{G'} - \theta_G$ plane is found from the Tevatron data on the cross section $\sigma_{t\bar{t}}$ and forward-backward asymmetry $A_{\rm FB}^{p \bar p}$ of the $t\bar{t}$ production. The mass limits for the $G'$-boson are shown to be stronger than those for the axigluon. A possible effect of the $G'$-boson on the $t\bar{t}$ production at the LHC is discussed and the mass limits providing for the $G'$-boson evidence at the LHC are estimated in dependence on $\theta_G$.Comment: 11 pages, 2 figures, accepted for publication in Modern Physics Letters

The soft and the hard pomerons: elastic scattering and unitarisation

The hard pomeron component needed to reproduce small-x data seems to be present in elastic scattering at moderate energy. If this is the case, it is likely that the total cross section at the LHC will be appreciably larger than previously expected.Comment: Talk given at 12th International Conference on Elastic and Diffractive Scattering: Forward Physics and QCD, Hamburg, DESY, Germany, 21-25 May 200

Hard pomeron contribution to forward elastic scattering

The introduction of a hard singularity in fits to total cross sections and to the ratio of real to imaginary parts enables to reproduce perfectly the data for sqrt(s)< 100 GeV using only simple-pole parametrisations, both for the soft and for the hard pomerons.Comment: Contribution to the proceedings of the XIth International Conference on Elastic and Diffractive Scattering, Chateau de Blois, France, May 15 - 20, 2005. Needs Blois.sty (provided

Potentiation of the antimicrobial effect of Lactobacillus reuteri DSM 17938 cell-free extracts by ascorbic acid.

The purpose of this study was to evaluate the effect of supplementing the culture medium with ascorbic acid on the antimicrobial properties of Lactobacillus reuteri cell-free extracts (CFEs). CFEs were prepared using commercial strain L. reuteri DSM 17938 by culturing lactobacilli in its own disintegrated cell suspension (DCS) supplemented with ascorbic acid in sub-inhibitory (5 mg/ml, CFE5) or minimal inhibitory concentration (20 mg/ml, CFE20) and without supplementation (CFE0). Staphylococcus aureus AТСС 25923, Escherichia coli AТСС 25922 reference strains and Pseudomonas aeruginosa extensively drug resistant (XDR) clinical isolate were used as indicator cultures. Screening of the inhibitory properties of the studied CFEs and elucidation of the nature of inhibitory products were done using modified Micro scale Optical Density Assay (MODA). The inhibition indices (InhI) were calculated for the studied CFEs and ascorbic acid of appropriate concentrations. CFEs were subjected to HPLC-analysis. CFE5 and CFE20 showed significantly higher antimicrobial activity toward to indicator cultures than CFE0. InhI calculated for extracts CFE5 and CFE20 mainly exceeded the sum of the corresponding indicators calculated for CFE0 and ascorbic acid (АА) of appropriate concentrations: InhICFE5 ≥ InhI CFE0 + InhI AA5; InhICFE20 &gt; InhI CFE0 + InhI AA20. Acidic metabolic products have made the greatest contribution to the antimicrobial effect of the studied CFEs. HPLC-nalysis showed that the modified ascorbic acid was the substance found in CFE20 in the greatest quantity. The revealed effect of potentiation of antimicrobial activity of CFEs by ascorbic acid should be taken into account when developing new biotechnological products based on derivatives of L. reuteri DSM 17938