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Spatio-temporal precipitation is modelled for urban application at 1 h temporal resolution on a 2 km grid using a Spatio-Temporal Neyman--Scott Rectangular Pulses weather generator (WG). Precipitation time series for fitting the model are obtained from a network of 60 tipping-bucket rain gauges irregularly placed in a 40 by 60 km model domain. The model simulates precipitation time series that are comparable to the observations with respect to extreme precipitation statistics. The WG is used for downscaling climate change signals from Regional Climate Models (RCMs) with spatial resolutions of 25 and 8 km respectively. Six diferent RCM simulations are used to perturb the WG with climate change signals resulting in six very different perturbation schemes. All perturbed WGs result in more extreme precipitation at the sub-daily to multi-daily level and these extremes exhibit a much more realistic spatial pattern than what is observed in RCM precipitation output. The WG seems to correlate increased extreme intensities with an increased spatial extent of the extremes meaning that the climate-change-perturbed extremes have a larger spatial extent than those of the present climate. Overall, the WG produces robust results and is seen as a reliable procedure for downscaling RCM precipitation output for use in urban hydrology. [ABSTRACT FROM AUTHOR]

We investigated the effect of changing the horizontal resolution of a regional climate model (RCM) on the simulation of hydrological extremes. We employed the results of three experiments of the RCM HIRHAM using a grid size of approximately 12, 25 and 50 km. These simulations were used to drive the hydrological model LISFLOOD, developed for flood forecasting at European scale. The discharge simulations of LISFLOOD were compared with statistics of observed river runoff at 209 gauging stations across Europe. The largest discrepancies in peak flow occurred in climates with a seasonal snow cover, which may be explained by inaccuracies in the simulated precipitation that accumulate over winter. Although previous studies have found that high resolution climate simulations result in more realistic patterns of extreme precipitation, especially in mountainous regions, we did not find conclusive evidence that the 12-km HIRHAM run generally yields a better simulation of peak discharges. At some gauging stations the model performance is increasing with increasing horizontal resolution of the RCM, while at other stations it is decreasing. However, the differences between the three experiments become less important in larger river basins. Above about 30 000km[sup2] and 120 000km[sup2], respectively, the 25- and 50-km runs generally provided a good approximation of the simulations based on the 12-km climatology. Under the A2 scenario of climate change, the changes in extreme discharge levels were similar between the three experiments at continental scale. At the scale of individual river basins, however, there were occasionally important differences. If we assume the 12-km HIRHAM simulation to be more realistic, the use of lower-resolution climate simulations may lead to an underestimation of future flood hazard. This means that results obtained with lower-resolution RCM simulations should be interpreted with care, as the grid scale of the climate model adds to the uncertainty. [ABSTRACT FROM AUTHOR]

Background and Objective: Various factors such as hormones, drugs, and ultraviolet (UV) radiation may influence patch test reactions. The aim was to study the individual variation in nickel reactivity, also in relation to the menstrual cycle., Methods: Thirty women allergic to nickel were studied for 7 months with patch tests with a serial dilution of nickel sulfate in water on four different test occasions. The patients belonged to two different eczema groups, one with nickel allergy, atopy, and pompholyx (12 patients); and the other with nickel allergy, but without both atopy and hand eczema., Results: None of the patients showed the same patch test reactivity on all four occasions, and the highest individual difference noticed was 250 times for the four test occasions. Furthermore, two of the patients had completely negative test reactions on at least one test occasion., Conclusion: The variation in nickel reactivity as shown in this article is of great importance and should be kept in mind when a patient has a positive history of allergic contact dermatitis but negative patch test results to nickel.

Background: Chronic wounds have been shown to exhibit elevated levels of several classes of proteinases. Plasminogen activators (PAs) are proteinases which play a major role in the biological processes involved in wound healing and abnormalities in PAs may play a role in the pathology associated with chronic wounds. Here, we investigated the expression of tPA and uPA activities in chronic venous ulcer biopsies., Patients and Methods: In 22 patients with chronic venous leg ulcers, punch biopsies were taken from the ulcer base, ulcer margin and uninvolved skin from the thigh of the affected limb and PA activities were assessed using in situ histological zymography., Results: tPA is the main PA activity in uninvolved skin but was reduced in ulcer margin skin and venous leg ulcer tissue compared to normal skin. uPA activity appeared throughout the ulcer margin skin but was at low levels in normal skin. Ulcer base tissue appeared to exhibit a plasminogen-independent proteinase activity not seen in normal or ulcer margin skin., Conclusion: PA activities are altered in and around chronic venous leg ulcers and their distribution suggests that blood vessels in CVI may be damaged and that the tissue is in an inflamed state.

Several factors, such as amount of allergen, vehicle, anatomic site, immunologic status and previous eczema, may influence delayed hypersensitivity reactions. In an extended model, we have studied the significance of previous allergic contact dermatitis for elicitation of delayed hypersensitivity to nickel in 25 nickel-allergic females. On 3 occasions, 8, 4 and 1 months before the final challenge patch testing, an experimental allergic contact dermatitis from nickel was induced on the lower back. At the challenge patch testing, 4 identical dilution series of nickel were tested on 4 areas on the lower back 3 with previous but healed dermatitis and 1 control area. The tests were read in a blind way. A significantly higher test reactivity was found at the areas with a previous allergic contact dermatitis, the shorter the time interval between the previous provocation and the challenge, the stronger the reaction. These results may be of importance for the understanding of factors contributing to chronicity of allergic contact dermatitis.

In total, 256 patients with bacteriologically verified impetigo contagiosa were included in three double-blind, parallel group, randomized, multi-centre trials, where the efficacy of hydrogen peroxide cream (Microcid) was compared with that of fusidic acid cream/gel (Fucidin). The trials were performed at 47 centres in three countries, Sweden, Germany and UK, and the results are compiled in the present report. During the course of the 3-week treatment period, 92 patients out of 128 (72%) in the Microcid group were classified as healed, compared to 105 patients out of 128 (82%) in the Fucidin group. This difference was not statistically significant. The reduction in composite sign severity score (the sum of the score for erythema, vesiculation/bullae, weeping and crusting divided by four) in each separate study was 73%, 78% and 84% in the Microcid group and 85%, 85% and 84% in the Fucidin group. No statistically significant differences were found in the separate studies or when compiling the studies in a meta-analysis. When the patients had been classified as healed, beta-haemolytic streptococci were eliminated in all patients treated with Microcid cream. Since treatment started before the result of the bacteriology was known, another 135 patients with negative skin culture were enrolled in the trials, i.e. 391 patients were included in the safety analysis. Out of these, 23 patients reported the occurrence of adverse events, mainly classified as mild. In conclusion, Microcid cream has been documented as a topical alternative to fusidic acid in the treatment of impetigo.