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When diphtheria was a common disease, it most commonly affected children. Typically, at least 40% of diphtheria cases were children under 5 years of age, and some 70% of cases were children under 15 years of age. This classical pattern of diphtheria cases

Population based surveillance was undertaken to assess the incidence of meningitis caused by Haemophilus influenzae type b in children 0-59 months old in Kielce and Bydgoszcz districts in Poland in 1998 and 1999. The cases were prospectively identified in pediatric and neuroinfection wards of local hospitals where all cases of children with suspected meningitis are referred in both districts. The mean annual incidence of meningitis caused by Haemophilus influenzae type b in children 0-59 months old in Kielce district during the study period was estimated at 3.1 per 100,000 per year (10.3% of cases of bacterial meningitis with confirmed etiology). In Bydgoszcz district, the annual incidence was 9.7 per 100,000 (50% of confirmed cases). These estimations are lower than reported in most Western European countries before the immunization against Hib was introduced. Small numbers of Hib vaccinations reported from both districts do not seem likely to have influenced the data significantly.

The study of epitaxial graphene layers grown on SiC by two techniques, namely, the traditional Si sublimation method and the recent chemical vapor deposition (CVD) using temperature induced shift of the Raman 2D line, is presented. The measurements of thermal shift rate of 2D line on 4 H-SiC(0001) allowed us to determine notable differences in interaction of graphene with SiC substrate. The obtained results show that graphene layers grown by Si sublimation of 4 H-SiC(0001) are pinned strongly to the substrate. In contrast, the layers of graphene grown on 4 H-SiC(0001) substrates by CVD showed much weaker pinning. It was found that the film consisting of two or three graphene layers grown by CVD was already unpinned and thus showing Raman shift expected for freestanding graphene. The obtained differences in pinning of epitaxial graphene layers are explained in terms of basic growth mechanism differences between these two methods: graphene growth by Si sublimation is a “bottom-up” process and by CVD—a “top-...

Gait transitions during long distance, unrestrained locomotion were studied in 22 mongrel dogs. Spatial and temporal limb movement parameters were collected and the phase relationships between limb movements based upon a 2-dimensional (2-D) gait diagram were computed. During most of the trials, the dogs trotted within a relatively narrow velocity range. Gait transitions were observed during radical changes of the movement velocity. In most cases the gait switches were abrupt and completed within 2 strides of the gait cycle. The dogs walked, depending on the animal size, within the upper velocity range of 0.93-1.21 m/s. Most of the walk-trot transitions were observed within this range. All of them had a typical pattern that involved changes of the phase shift between diagonal limb movements from 0.31 +/- 0.02 (a typical value for a walking dog) down to 0.02 +/- 0.03. These changes appeared abruptly within one stride cycle for each diagonal pair of limbs; therefore, the transition was completed in 2 strides of the gait cycle. The switch involved momentary shortening of the hindlimb amplitudes. During the next gait cycle, all limb movement amplitudes were reduced with a concomitant increase in limb movement frequencies. In contrast to the clear border between the symmetrical gaits, the dogs switched to gallop at any speed within the trot range (most frequently between 1.5-2.6 m/s). The transitions were usually completed within one stride of the diagonal limbs. In most cases, the switch from trot to gallop had a similar pattern; while maintaining synchronous movement of one diagonal pair of limbs, the other pair movement control was modified accordingly. The typical transition pattern involved the shortening of the swing phase in the front limb with simultaneous lengthening of the swing phase in the diagonal hindlimb. These transient modifications had their equivalent in the analogous limb movement amplitude changes. A mirror-image pattern of phase changes was observed in the majority (82%) of the gallop-trot transitions. Three of the dogs, however, besides the typical gallop-trot switch, occasionally employed a second pattern of transition.