Hubert van den Bergh

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The first effective therapy for exudative macular degeneration (AMD) was Photodynamic Therapy (PDT). Diagnosis of the disease was to a large extent by fluorescein angiography (FA). Distinguishing between the leaky choroidal neovessels (CNV) associated with exudative AMD, and the polypoidal structures associated with Polypoidal Choroidal Vasculopathy (PCV)(More)
Exogenous administration of 5-aminolaevulinic acid (ALA) is becoming widely used to enhance the endogenous synthesis of protoporphyrin IX (PpIX) in photodynamic therapy (PDT) and fluorescence photodetection (PD). Recently, results have shown that the chemical modification of ALA into its more lipophilic esters circumvents limitations of ALA-induced PpIX(More)
Light propagation in two-layered turbid media that have an infinitely thick second layer is investigated with time-resolved reflectance. We used a solution of the diffusion equation for this geometry to show that it is possible to derive the absorption and the reduced scattering coefficients of both layers if the relative reflectance is measured in the time(More)
The popular statistical theory of absolute diffuse reflectance of powders put forth by Melamed [J. Appl. Phys. 34, 560-570 (1963)] a quarter century ago has been re-examined thoroughly. Substantial errors in the physical formulation of the theory have been found and a corrected version is being presented. Some of Melamed's data fits to the theory are also(More)
Article history: Available online xxxx Keywords: Atmospheric boundary layer Raman lidar Water vapor a b s t r a c t A new multi-telescope scanning Raman lidar designed to measure the water vapor mixing ratio in the atmospheric boundary layer for a complete diurnal cycle with high resolution spatial (1.25 m) and temporal (1 s) resolutions is presented. The(More)
Water vapour has been measured from the International Scientific Station Jungfraujochcrowave radiometry and Raman lidar. The abundance of atmospheric water vapour between the planetary boundary layer and the upper stratosphere varies over more than 5 three orders of magnitude. The currently used measurement techniques are suited to determine the abundance(More)
Air pollution measurements are aimed at improving our understanding of the chemical properties of the atmosphere, addressing mainly three issues with very different space and time scales: • Measurement of critical or peak values of air pollutant in densely urbanized/industrialized sites. • Long term observation and trend analysis on air quality. •(More)