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Exact close-coupling calculations for H2 rigid rotor scattering from a LiF (001) surface are presented. Using a standard model potential, rotation-diffraction transition probabilities are reported for a range of collision energies up to 0.7 eV and for various surface corrugations. The calculations are aimed to serve as a reference for approximate approaches. The exact transition probabilities are compared with existing quasiclassical trajectory calculations and with results obtained by the matrix-diagonalization sudden method. In agreement with previous approximate treatments it is found that the coupling between rotations and diffractions is only weak so that both can essentially be treated independently. [ABSTRACT FROM AUTHOR]

The interaction potential for the elastic diffractive scattering of low-energy He atoms from the highly corrugated LiF(001) crystal surface is derived from semi ab initio pair potentials in the framework of the recently developed Tang–Toennies potential model [J. Chem. Phys. 80, 3726 (1984)]. In addition to the sum of all He atom-crystal ion two-body potentials the induced dipole potential caused by the electric field of the ion lattice is taken into account, leaving only one free parameter, the C6 dispersion constant of the He–F- interaction. By simple adjustment of this parameter, it is possible to fit all of the experimental bound states of the atom-surface potential well, to within experimental error. Diffraction probabilities calculated by the close coupling method with this potential are shown to be in good agreement with the available experimental results. Two different empirical potential models based on the Morse potential are also investigated, but do not provide as good a description of the bound states and diffraction intensities. [ABSTRACT FROM AUTHOR]

Objective. Combination vaccines simplify vaccine administration and have the potential to promote compliance and cost-effectiveness by decreasing the number of injections needed to immunize a child. The objective of this study was to assess the safety and reactogenicity of the diphtheria-tetanus toxoid-acellular pertussis-hepatitis B virus-inactivated polio virus (DTPa-HBV-IPV) vaccine when coadministered with different Haemophilus influenzae type B (Hib) vaccines in comparison with separate, commercially available, control vaccines in a 3-dose primary vaccination series. Methods. An open-label, randomized, parallel-group study in 5318 infants who were 8 to 16 weeks of age at enrollment was conducted in 90 centers in Germany. The incidence of adverse events that occurred in infants who received the DTPa-HBV-IPV candidate vaccine coadministered with 1 of 4 different Hib vaccines (given in separate sites; groups 1-4) was compared with the incidence that occurred in infants who received commercially available control vaccines (DTPa, Hib, and oral polio virus [OPV] vaccine; group 5) administered separately. The vaccines were given as a 3-dose primary series at 3, 4, and 5 months of age. Infants were assessed for solicited local and general adverse events for 4 days and for unsolicited adverse events for 30 days after each vaccine dose. The primary endpoint was to rule out a 7.5% increase in infants who experienced grade 3 (defined as preventing normal everyday activities unless otherwise specified) solicited local and general adverse events over the 3-dose primary course after the combined DTPa-HBV-IPV vaccine coadministered with Hib as compared with commercially available vaccines. Results. During the 3-dose primary course, 490 of 3029 infants (16.2%) in the pooled DTPa-HBV-IPV vaccine groups and 151 of 744 (20.3%) in the control vaccine group experienced a grade 3 adverse event (rate difference [control minus combination] 4.1%; 90% confidence interval, 1.41-7.13). The lower limit of the 90% confidence interval of the observed difference remained above the prespecified -7.5% limit for noninferiority, thereby meeting the primary endpoint. The incidences of local injection-site reactions were similar for the DTPa-HBV-IPV and DTPa injection sites. Significant differences in the incidence of both local and general adverse events were observed depending on which of the Hib vaccines was coadministered. Infants who received Hib N meningitidis outer-membrane complex protein conjugate vaccine had greater incidences of fever and, to a lesser extent, greater reactions at the Hib injection site than did infants who received other Hib vaccines. Conclusions. The combination DTPa-HBV-IPV vaccine administered concomitantly with Hib vaccine at separate sites was at least as safe as coadministration of individual DTPa, Hib, and OPV vaccines in terms of the defined endpoints for safety. Pediatrics 2002;109(4). URL: http://www.pediatrics.org/cgi/content/full/109/4/e58; combination vaccine, diphtheria, pertussis, tetanus, hepatitis B virus, Haemophilus influenzae type b, polio.