Background: Little knowledge exists on the availability of academic and community paediatric neurology positions. This knowledge is crucial for making workforce decisions. Our study aimed to: 1) obtain information regarding the availability of positions for paediatric neurologists in academic centres; 2) survey paediatric neurology trainees regarding their perceptions of employment issues and career plans; 3) survey practicing community paediatric neurologists 4) convene a group of paediatric neurologists to develop consensus regarding how to address these workforce issues. Methods: Surveys addressing workforce issues regarding paediatric neurology in Canada were sent to: 1) all paediatric neurology program directors in Canada (n=9) who then solicited information from division heads and from paediatric neurologists in surrounding areas; 2) paediatric neurology trainees in Canada (n=57) and; 3) community paediatric neurologists (n=27). A meeting was held with relevant stakeholders to develop a consensus on how to approach employment issues. Results: The response rate was 100% from program directors, 57.9% from residents and 44% from community paediatric neurologists. We found that the number of projected positions in academic paediatric neurology is fewer than the number of paediatric neurologists that are being trained over the next five to ten years, despite a clinical need for paediatric neurologists. Paediatric neurology residents are concerned about job availability and desire more career counselling. Conclusions: There is a current and projected clinical demand for paediatric neurologists despite a lack of academic positions. Training programs should focus on community neurology as a viable career option.

Varicella-zoster virus causes chickenpox (CP) and after reactivation herpes zoster (HZ). Vaccines are available against both diseases warranting an assessment of the pre-vaccination burden of disease. We collected data from relevant Belgian databases and performed five surveys of CP and HZ patients. The rates at which a general practitioner is visited at least once for CP and HZ are 346 and 378/100 000 person-years, respectively. The average CP and HZ hospitalization rates are 5·3 and 14·2/100 000 person-years respectively. The direct medical cost for HZ is about twice as large as the direct medical cost for CP. The quality-adjusted life years lost for ambulatory CP patients consulting a physician is more than double that of those not consulting a physician (0·010 vs. 0·004). In conclusion, both diseases cause a substantial burden in Belgium.

A series of large-eddy simulations of plane Poiseuille flow are discussed. The subgrid-scale motions are represented by an eddy viscosity related to the flow deformation — the ‘Smagorinsky’ model. The resolution of the computational mesh is varied independently of the value of the coefficient Cs which determines the magnitude of this subgrid eddy viscosity. To ensure that results are from a statistically steady state unrealistic initial conditions are used and sufficient time is allowed for the flow to become independent of the initial conditions. In keeping with previous work it is found that for large Cs the resolved-scale motions are damped out; however, this critical value of Cs is found to depend on the mesh resolution. Only with a fine mesh does the value of Cs previously found to be appropriate for homogeneous turbulence (≈ 0.2) give simulations with sustained resolved-scale motions. The ratio l0/δ of the channel width 2δ to the scale of the ‘Smagorinsky’ mixing length, l0 = CsΔ where Δ is a typical mesh spacing), is found to be the key parameter determining the ‘turbulent’ eddy-viscosity ‘Reynolds number’ of the resolved-scale motions. A fixed value of 10 is regarded as determining the separation of scales into resolved and subgrid. The value of l0 is regarded as a measure of numerical resolution and values of Cs less than about 0.2 correspond to inadequate resolution.

The potential of Er-doped Cs2NaYF6 and GaN for mid-infrared emission at λ≈ 2.7 ν is investigated using time-resolved optical spectroscopy. This emission results from electronic transitions between the second (4I11/2) and first (4I13/2) excited states of the Er3+ ion. By recording the photoluminescence transients for the 4I11/2 → 4I15/2 and 4I13/2 → 4I15/2 transitions after pulsed excitation, we determine the lifetime of the 4I11/2 level and demonstrate that the 4I13/2 state is populated from this level. Our results indicate that both host lattices should enable 2.7 νm emission, which is temperature-stable but subject to concentration quenching.

Recent developments in the area of cost effective 2D direct x-ray sensor arrays on the base of a-SiN:H back-to-back Schottky diodes and no switching devices per pixel are presented. Discussion focuses on two major aspects: (i) x-ray sensitivity of the sensor itself and possibility of its improvement; (ii) the overall performance of the sensor array.

A number of localizations for the putative susceptibility gene(s) have been identified for both Crohn's disease and ulcerative colitis. In a genome wide scan, Hugot et al. (1996) identified a region on chromosome 16 which appeared to be responsible for the inheritance of inflammatory bowel disease in a small proportion of families. Subsequent work has suggested that this localization is important for susceptibility to Crohn's disease rather than ulcerative colitis (Ohmen et al. 1996; Parkes et al. 1996). We investigated the contribution of this localization to the inheritance of inflammatory bowel disease in 54 multiplex Australian families, and confirmed its importance in a significant proportion of Crohn's disease families; we further refined the localization to a region near to D16S409, obtaining a maximum LOD score of 6.3 between D16S409 and D16S753.