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Background: Sclerotherapy is considered to be the method of choice for the treatment of telangiectatic varicose veins (C1 veins). Whereas the use of compression stockings after sclerotherapy is recommended, little is known about the impact of compression on the outcome of sclerotherapy. The aim of this study was to assess the influence of compression on the outcome of injection sclerotherapy of C1 varicose veins. Methods: There were 100 legs of 50 consecutive patients with chronic venous insufficiency (C1) included. After randomization per patient, both legs were treated with sclerotherapy in a predefined area of the thigh (measuring 100 cm2), followed by eccentric compression for 24 hours. Group A received no further compression, whereas group B was additionally equipped with compression stockings of 18 to 20 mm Hg above the ankle and continued wearing these for 1 week. Photodocumentation was performed before, 1 week after, and 4 weeks after sclerotherapy, and the clinical outcome was assessed at these postprocedure follow-up dates. The photographs were reviewed by an internal unblinded rater and an independent blinded external rater. Results: There was no discernible difference between the groups in terms of clinical outcome or side effects after 4 weeks. Whereas inter-rater reliability was high, there was no correlation between the raters and patients in terms of outcome. In 55% of the treated legs, the patients deemed the result of the treatment to be good; in 27% of the treated legs, fair; and in 18%, poor. Postprocedure hyperpigmentation occurred in 13% of patients and was comparable in both groups. Compression therapy was found to be comfortable by the majority (58%) of patients. Conclusions: One week of postinterventional compression therapy had no clinical benefit compared with no compression.

Background For effective compression therapy in patients with venous leg ulcers, sufficient pressure is essential. In everyday life, it is often the patients themselves who apply the compression bandages. Many of these patients have restriction in their movement and had been rarely trained adequately. Hence, there was the question of how efficient are the autonomously applied compression bandages of those patients. Patients and methods In all, 100 consecutive patients with venous leg ulcer were asked to apply compression bandages on their own leg. We documented both the achieved compression and formal criteria of correct performance. Results A total of 59 women and 41 men with an average age of 70.3 years were included in the study. Overall 43 patients were not able to apply a compression bandage because of physical limitations. The measured pressure values in the remaining 57 patients ranged between 6 and 93 mm Hg (mean 28.3 mm Hg). Eleven patients reached the prescribed effective compression pressure. Of these, formal errors were found in 6 patients, so that only 5 patients had correctly applied the compression bandages. Conclusion Our data show that most patients with venous leg ulcers are not able to apply effective compression therapy with short-stretch bandages to themselves. Multilayer systems, adaptive compression bandages, and ulcer stocking systems today are possibly easier and more effective therapy options. Alternatively short-stretch bandages could be applied by trained persons but only under the control with pressure measuring probes.

Compression therapy is well-tried treatment with only few side effects for most patients with leg ulcers and/or edema. Despite the very long tradition in German-speaking countries and good evidence for compression therapy in different indications, recent scientific findings indicate that the current situation in Germany is unsatisfactory. Today, compression therapy can be performed with very different materials and systems. In addition to the traditional bandaging with Unna Boot, short-stretch, long-stretch, or multicomponent bandage systems, medical compression ulcer stockings are available. Other very effective but far less common alternatives are velcro wrap systems. When planning compression therapy, it is also important to consider donning devices with the patient. In addition to compression therapy, intermittent pneumatic compression therapy can be used. Through these various treatment options, it is now possible to develop an individually accepted, geared to the needs of the patients, and functional therapy strategy for nearly all patients with leg ulcers.

In dieser Arbeit wurden die Eigenschaften eines Kohlenstoff-Faserverbundwerkstoffs unter quasistatischer Druckbelastung untersucht und modellhaft beschrieben. Der Werkstoff wurde durch Pyrolyse hergestellt und besteht aus bidirektional verstarkten Gewebelagen. Fur die Druckversuche wurde eine Vorrichtung zur Vermeidung uberlagerter Biegebeanspruchung angefertigt. Das Spannungs-Dehnungsverhalten dieses Werkstoffs wurde schon in verschiedenen Veroffentlichungen wiedergegeben. Hier wird auf das Bruchverhalten eingegangen und die experimentellen Ergebnisse aus den Druckversuchen den Kennwerten aus Zug- und Scherversuchen gegenubergestellt. Die unterschiedlichen Druck- und Zugeigenschaften von Steifigkeit, Querkontraktion und Festigkeit wurden bewertet. Unterschiede zwischen Zug- und Druckverhalten ergeben sich bei Belastung in Faserrichtung durch lokales Ausknicken und Rissschliesung. Erfolgt die Belastung nicht in Faserrichtung, fuhren uberlagerte Druck-Normalspannungen zu erhohter Scherreibung. In this work the properties of Carbon/Carbon-material are investigated under quasi-static compression and model-like characterized. The investigated material was produced by pyrolysis of a Carbon/Carbon – composite of bidirectionally reinforced fabric layers. For the compression tests, a device to prevent additional bending stress was made. The stress-strain behaviour of this material has been reproduced in various publications. This will be discussed on the fracture behaviour and compared the experimental results from the compression tests with the characteristics of tensile and shear tests. The different compression and tensile properties of stiffness, poisson and strength were assessed. Differences between the tensile and compression behaviour resulting from on-axis tests by micro buckling and crack closure and off-axis experiments by superimposed pressure normal stresses that lead to increased shear friction.

This paper presents the numerical simulations and performance analysis of a 3D scramjet inlet with focus on the effects of sidewall compression and relaminarization. A well-validated �finite volume flow solver was used to simulate a scramjet inlet with a double ramp configuration for outer compression and varying degrees of sidewall compression. The computed wall pressure and heat transfer in the symmetry plane are in close agreement with the measurements and numerical results indicate that sidewall compression alters the inlet performance significantly. The effects of relaminarization over the expansion corner prior to the interior part of the inlet is isolated and studied in both experiment and simulation.

The ablative material ZURAM has been developed by the German Aerospace Center DLR. It is manufactured from a rigid carbon felt impregnated with phenolic resin. It has a low density of approximately 0.36 – 0.4 g/cm³. Arc jet tests were carried out up to heat fluxes of 13.5 MW/m² indicating the potential of the material with recession rates of approximately 0.3 mm/s. To characterize the material in detail to facilitate the design for space vehicles, the complete set of thermal and mechanical material properties has to be established. This paper will present the determination of the mechanical properties related to the microstructure. A characterization in tension, compression and shear was carried out resulting in the respective moduli and strength values. It was found that the material has an anisotropic behavior. Since the material is rather delicate in comparison to other structural materials, stress and strain measurements were in part also based on optical measurements to not disturb the material response.