Mesenchymal stem cells in lymph node development and disease

Mebius, R.E. [Promotor

Mogelijkheden van indikken van melk op de boerderij = Possibilities of concentrating milk on-farm

This report described the possibilities of concentrating milk on the farm. It covers the technique to remove water from milk and all aspects as to quality, processing, legislation and economic feasibilit

Visible light tomography on RTP

A diagnostic for visible light tomography is being prepared for the Rijnhuizen Tokamak Project (RTP). Light emitted in the range of 200 to 1100 nm will be detected by five cameras positioned around the plasma in one poloidal plane. Each camera has 16 detector elements. The 80 channels are provided with parallel electronics with a bandwidth of 200 kHz. Imaging systems are used to collect the light on the detector elements. The resolution of this system is of the order of 1 cm. Optical filters in front of the detectors can select interesting wavelength ranges, such as spectral lines or a line-free part of the continuum radiatio

Experimental evaluation of the power balance model of speed skating

Prediction of speed skating performance with a power balance model requires assumptions about the kinetics of energy production, skating efficiency, and skating technique. The purpose of this study was to evaluate these parameters during competitive imitations for the purpose of improving model predictions. Elite speed skaters (n = 8) performed races and submaximal efficiency tests. External power output (Po) was calculated from movement analysis and aerodynamic models and ice friction measurements. Aerobic kinetics was calculated from breath-by-breath oxygen uptake (V̇O2). Aerobic power (Paer) was calculated from measured skating efficiency. Anaerobic power (Pan) kinetics was determined by subtracting P aer from Po. We found gross skating efficiency to be 15.8% (1.8%.). In the 1,500-m event, the kinetics of Pan was characterized by a first-order system as Pan = 88 + 556e-0.0494t (in W, where t is time). The rate constant for the increase in Paer was -0.153 s-1, the time delay was 8.7 s, and the peak Paer was 234 W; Paer was equal to 234[1 - e-0.153(t-8.7)] (in W). Skating position changed with preextension knee angle increasing and trunk angle decreasing throughout the event. We concluded the pattern of P aer to be quite similar to that reported during other competitive imitations, with the exception that the increase in Paer was more rapid. The pattern of Pan does not appear to fit an "all-out" pattern, with near zero values during the last portion of the event, as assumed in our previous model (De Koning JJ, de Groot G, and van Ingen Schenau GJ. J Biomech 25: 573-580, 1992). Skating position changed in ways different from those assumed in our previous model. In addition to allowing improved predictions, the results demonstrate the importance of observations in unique subjects to the process of model construction