Heavy Load Rollers in Logistic Systems

Wheels with polyurethane bandages are in common use in logistic systems with friction gear actuation. Many research projects have studied the mechanical construction of these heavy load wheels. The studies have been theoretical as well as experimental. Research interests at the department of machine elements include the wear in the presence of intermediate material on the contact area between the bandage surface and the contact surface on which the wheel rolls off. This problem, which is observed when examining this tribochemical system, has not been studied before. Within this project both one-phase intermediate materials such as sand, water, cutting-cooling-emulsion, metal splinters and two-phase intermediate materials such as sand/water and combinations of the latter were taken into consideration. In addition, the exposure of the bandage hardness, the cross linking agent of the polyurethane, the mechanical stress, and the slip are observed. The analysis of the experimental results indicates that friction gear actuators can be constructed abrasion-optimised, taking into account special interfering effects in the form of intermediate materials in the contact area

Experimentelle Verschleissuntersuchungen von angetriebenen Polyurethan-Raedern unter Einwirkung von Zwischenstoffen

The wear behavior of wheels wrapped with polyurethane bandages, that are used in gears, has been studied. Different materials between the wheel surface and the contacting layer transfer a tangential driving force into the contact layer. The abrasive effects of sand, water, sand with water, cooling emulsions for cutting, metal chips, and cooling emulsions containing metal chips, have been evaluated in 24 hours wear tests. Severe abrasion of the PU coating has been observed with grinding materials like sand and metal chips.SIGLEAvailable from: http://eldorado.uni-dortmund.de:8080/FB7/Is2/forschung/2002/Mehlan/Mehlanunt.pdf / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman

Das Deutsche Pilz-Keratitis-Register

Background and purpose. Mycotic keratitis is a serious but relatively rare disease. No targeted data collection in Germany existed until the foundation of the German Pilz-Keratitis Register in 2015. Patients and methods. The inclusion of retrospective and prospective patients was carried out. Inclusion criteria: diagnosis confirmed by the polymerase chain reaction (PCR), culture, histology or confocal microscopy (IVCM). Collected parameters: date of symptom onset, date and method of diagnosis, risk factors, visual acuity and findings at admission and at follow-up, conservative and surgical treatment. Results. By January 2018, a total of 102 eyes from the years 2000-2017 were reported from 16 centers (64.3% female, mean age 52 years, range 18-95 years). The initial diagnosis was made correctly in only 20.6% of cases. The mean time to correct diagnosis was 31.7 +/- 46.9 (0-296) days. The diagnosis was confirmed in cultures in 74.5%, histologically in 30.4%, by PCR in 38.2% and IVCM in 27.4%. Fungal species identified were: 36.7% Fusarium spp., 35.8% Candida spp., 6.4% Aspergillus spp. and 21.1% other. The most important risk factor was the use of contact lenses. The most commonly used antifungal agent was voriconazole (64.7%) followed by amphotericin B (37.2%). Penetrating keratoplasty was performed in 65.7% of the cases and 8.8% of the affected eyes had to be enucleated. The visual acuity of the entire study population increased from the initial 0.16 +/- 0.25 (0.001-1.0) decimal to 0.28 +/- 0.34 (0-1.0) decimal. Conclusion. The correct diagnosis of fungal keratitis is often significantly delayed. The treatment can be very difficult and keratoplasty is often necessary. In order to gain a better understanding of this disease, to recognize previously unknown risk factors and, if necessary, a change in the spectrum of pathogens and to identify approaches to treatment optimization, the fungal keratitis registry will be continued

3-year results of the German nationwide survey on eye injuries caused by fireworks

Background On festive days worldwide eyes are severely injured by fireworks. The data on the number and severity are to date not registered in Germany. Objective How frequent are firework-induced injuries in Germany, who are the affected, how serious are the injuries, which forms of treatment are necessary and how frequent are accompanying injuries? Method A German nationwide online-based survey was carried out in all inpatient eye departments and data over the last 3 consecutive years were descriptively analyzed. Results From New Years Eve 2016/2017, when 41 eye departments sent in data, the participation could be increased to 51 eye departments in 2018/2019. More than one third (33-39%) of all 1356 patients over 3 years were minors, 60% were younger than 25 years old and roughly 60% of patients were injured as bystanders or in an unclear situation. In total 25% of all eye injuries were considered severe and required inpatient treatment. Accompanying injuries of the other eye, the face and hands were more frequent in minors than in adults. Eyeball ruptures were reported in 10 minors and 38 adults over the 3 years. Conclusion Particularly minors and bystanders need better protection