Modulation of humoral immune response to oral BCG vaccination by Mycobacterium bovis BCG Moreau Rio de Janeiro (RDJ) in healthy adults

Background  

Oral administration of BCG was the route initially used by Calmette and Guérin, but was replaced by intradermal administration in virtually all countries after the Lubeck accident. However, Brazil continued to administer oral BCG Moreau RDJ, which was maintained until the mid-1970s when it was substituted by the intradermal route. Although BCG vaccination has been used in humans since 1921, little is known of the induced immune response. The aim of this study was to analyse immunological responses after oral vaccination with M. bovis BCG Moreau RDJ.     

The kinetics of the thermal bromination of CF3I. Determination of the bond dissociation energy D(CF3−I)

The kinetics of the thermal bromination reaction have been studied in the range of 173–321°C. For the step we obtain where θ=2.303RT cal/mole. From the activation energy for reaction (11), we calculate that This is compared with previously published values of D(CF₃?I). The relevance of the result to published work on k_c for a combination of CF₃ radicals is discussed.     

The kinetics of the thermal gas-phase reaction Br2 + C6F5I → BrI + C6F5Br. An attempt to determine the bond dissociation energy D(C6F5-I)

The kinetics of the thermal bromination reaction have been studied in the range of 261°–391°C. The observed rate law is compatible with initiation by the step for which we obtain where Θ = 2.303RT cal/mol. Using the above value of E₆, we have This result disagrees with values of D(C₆F₅-I) obtained in other ways and we conclude that reaction (3) probably does not involve initiation by reaction (6). Instead, initiation may involve an addition of Br to the ring in C₆F₅I followed by decomposition of the adduct to give C₆F₅Br. If correct, this implies that the Arrhenius parameters above refer to the addition reaction rather than to reaction (6).     

The determination of the arrhenius parameters for the reaction Cl + C2F5I → ICl + C2F5 using a competitive method

The reactions have been studied competitively over the range of 28–182°C by photolysis of mixtures of Cl₂ + C₂F₅I+ CH₄. We obtain where θ = 2.303RT J/mol. The use of published data on reaction (2) leads to log (k₁cm³/mol sec) = (13.96 ± 0.2) ? (11,500 ± 2000)/θ.     

A Mössbauer study of rapidly quenchedCuFe alloys — Antiferromagnetic γ-Fe

A series ofCuFe alloys containing 5, 10 and 16 at% Fe has been prepared using standard ribbon spinning techniques. It is found that samples containing significant fractions ( 5%) of Fe in the form of r-Fe can be obtained readily on quenching from the (r + liquid) phase, applied field spectra (0–5.2 T) on antiferromagnetic r-Fe at 4. 2 K indicate that the anisotropy energy is small and that spins tilt from the minimum energy configuration (spin axes perpendicular to B_appl) for B_appl 2.5T.     

Analysis and display of the size dependence of chemical similarity coefficients

We discuss the size-bias inherent in several chemical similarity coefficients when used for the similarity searching or diversity selection of compound collections. Limits to the upper bounds of 14 standard similarity coefficients are investigated, and the results are used to identify some exceptional characteristics of a few of the coefficients. An additional numerical contribution to the known size bias in the Tanimoto coefficient is identified. Graphical plots with respect to relative bit density are introduced to further assess the coefficients. Our methods reveal the asymmetries inherent in most similarity coefficients that lead to bias in selection, most notably with the Forbes and Russell-Rao coefficients. Conversely, when applied to the recently introduced Modified Tanimoto coefficient our methods provide support for the view that it is less biased toward molecular size than most. In this work we focus our discussion on fragment-based bit strings, but we demonstrate how our approach can be generalized to continuous representations.     

The kinetics of the reactions of methyl radicals with Br2, Cl2, and BrCl

A general competitive method is described for the study of the kinetics of the reactions of radicals with halogens and interhalogen compounds in the gas phase. The method is applied to the reactions over the temperature range of 48°–199°C. It is found that where Θ=2.303RT J/mol. Also There is no correlation between differences in activation energies and differences in enthalpy changes for these reactions, but polar effects may be important in reactions (7) and (8).     

Ultra short pulse laser annealing of FeB metallic glasses

We present the results of picosecond laser annealing of as-quenched Fe₈₅B₁₅ and Fe₈₂B₁₈ metallic glasses. The influence of the laser radiation on the surface and bulk properties are studied using CrK X-ray diffraction and transmission Mössbauer spectroscopy. The X-ray data show that the amorphous nature of the surface of the samples can be improved with laser treatment. The mat (cooling) surfaces of the ribbons appear to be more affected by the laser treatment, and show a higher stability. The Mössbauer data reveal that laser annealing of ribbon surfaces also affects the bulk properties of these materials due to induced stresses from the surface layer. The magnetic properties of these materials can be modified by laser annealing.     

The kinetics of the reactions of C2F5 radicals with Br2 and HBr

A mixture of Br₂ + HBr + C₂F₅I was photolyzed in the vapor phase. The reaction forms C₂F₅ radicals which are removed by Competitive studies over the range of 74–146°C gave ratios of k₁₀/k₉, and these were combined with values obtained previously by different methods at higher temperatures upto 515°C to give where θ = 2.303RT J/mol. A value is assigned to the activation energy E₁₀, and this, with other data, leads to at 25°C. This result is in excellent agreement with two previous independent determinations.